diff --git a/C/absmi.c b/C/absmi.c
index 4b2d9086b..d8e3a2f17 100755
--- a/C/absmi.c
+++ b/C/absmi.c
@@ -2005,11 +2005,11 @@ Yap_absmi(int inp)
 	  }
 #endif	/* LOW_LEVEL_TRACER */
 #ifdef FROZEN_STACKS
-#ifdef SBA
+#ifdef YAPOR_SBA
 	  if (pt0 < TR_FZ || pt0 > (tr_fr_ptr)Yap_TrailTop)
 #else
 	  if (pt0 < TR_FZ)
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	    {
 	      TR = TR_FZ;
 	      TRAIL_LINK(pt0);
@@ -2022,7 +2022,7 @@ Yap_absmi(int inp)
 	d1 = TrailTerm(pt0-1);
 	pt0--;
 	if (IsVarTerm(d1)) {
-#if defined(SBA) && defined(YAPOR)
+#if defined(YAPOR_SBA) && defined(YAPOR)
 	  /* clean up the trail when we backtrack */
 	  if (Unsigned((Int)(d1)-(Int)(H_FZ)) >
 	      Unsigned((Int)(B_FZ)-(Int)(H_FZ))) {
@@ -2053,11 +2053,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS  /* TRAIL */
             /* avoid frozen segments */
 	    if (
-#ifdef SBA
+#ifdef YAPOR_SBA
 		(ADDR) pt1 >= HeapTop
 #else
 		IN_BETWEEN(Yap_TrailBase, pt1, Yap_TrailTop)
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 		)
             {
 	      pt0 = (tr_fr_ptr) pt1;
@@ -2238,11 +2238,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
       { 
 	choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	if (ENV > (CELL *) top_b || ENV < H) YREG = (CELL *) top_b;
 #else
 	if (ENV > (CELL *) top_b) YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	else YREG = (CELL *)((CELL)ENV + ENV_Size(CPREG));
       }
 #else
@@ -2277,11 +2277,11 @@ Yap_absmi(int inp)
       Op(save_b_x, x);
       BEGD(d0);
       d0 = PREG->u.x.x;
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       XREG(d0) = MkIntegerTerm((Int)B);
 #else
       XREG(d0) = MkIntegerTerm(LCL0-(CELL *) (B));
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, x);
       ENDD(d0);
       GONext();
@@ -2289,11 +2289,11 @@ Yap_absmi(int inp)
 
       /* save_b_y      Yi                 */
       Op(save_b_y, y);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.y.y,MkIntegerTerm((Int)B));
 #else
       YREG[PREG->u.y.y] = MkIntegerTerm(LCL0-(CELL *) (B));
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, y);
       GONext();
       ENDOp();
@@ -2315,11 +2315,11 @@ Yap_absmi(int inp)
       PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xps),Osbpp),l);
       {
 	choiceptr pt0;
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	pt0 = (choiceptr)IntegerOfTerm(d0);
 #else
 	pt0 = (choiceptr)(LCL0-IntegerOfTerm(d0));
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	saveregs();
 	prune(pt0);
 	setregs();
@@ -2351,7 +2351,7 @@ Yap_absmi(int inp)
       PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yps),Osbpp),l);
       {
 	choiceptr pt0;
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	pt0 = (choiceptr)IntegerOfTerm(d0);
 #else
 	pt0 = (choiceptr)(LCL0-IntegerOfTerm(d0));
@@ -2467,11 +2467,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
 	{ 
 	  choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	  if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
 #else
 	  if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	  else ENV_YREG = (CELL *)((CELL)ENV_YREG + ENV_Size(CPREG));
 	}
 #else
@@ -2536,11 +2536,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
 	{ 
 	  choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	  if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
 #else
 	  if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	}
 #else
 	if (ENV_YREG > (CELL *) B) {
@@ -2830,11 +2830,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
       { 
 	choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	if (YREG > (CELL *) top_b || YREG < H) YREG = (CELL *) top_b;
 #else
 	if (YREG > (CELL *) top_b) YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	else YREG = YREG + ENV_Size(CPREG);
       }
 #else
@@ -2856,11 +2856,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
       { 
 	choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	if (YREG > (CELL *) top_b || YREG < H) YREG = (CELL *) top_b;
 #else
 	if (YREG > (CELL *) top_b) YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	else YREG = YREG + ENV_Size(CPREG);
       }
 #else
@@ -2900,7 +2900,7 @@ Yap_absmi(int inp)
 	  { 
 	    choiceptr top_b = PROTECT_FROZEN_B(B);
 
-#ifdef SBA
+#ifdef YAPOR_SBA
 	    if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
 #else
 	    if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
@@ -2982,11 +2982,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
       { 
 	choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	if (YREG > (CELL *) top_b || YREG < H) YREG = (CELL *) top_b;
 #else
 	if (YREG > (CELL *) top_b) YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	else YREG = (CELL *) ((CELL)YREG + ENV_Size(CPREG));
       }
 #else
@@ -3152,11 +3152,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
       { 
 	choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
 #else
 	if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	else ENV_YREG = (CELL *)((CELL) ENV_YREG + ENV_Size(CPREG));
       }
 #else
@@ -3272,11 +3272,11 @@ Yap_absmi(int inp)
       pt0 = YREG + PREG->u.yx.y;
       d0 = XREG(PREG->u.yx.x);
       PREG = NEXTOP(PREG, yx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       GONext();
       ENDP(pt0);
       ENDD(d0);
@@ -3293,16 +3293,16 @@ Yap_absmi(int inp)
       pt1 = S_YREG + PREG->u.yyx.y2;
       d1 = XREG(PREG->u.yyxx.x2);
       PREG = NEXTOP(PREG, yyxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
-#if defined(SBA) && defined(FROZEN_STACKS)
+#endif /* YAPOR_SBA && FROZEN_STACKS */
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt1,d1);
 #else
       *pt1 = d1;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt1);
       ENDD(d1);
       GONext();
@@ -4383,11 +4383,11 @@ Yap_absmi(int inp)
       pt0 = RepPair(d0);
       d0 = pt0[1];
       ENDP(pt0);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.yx.y,d0);
 #else
       YREG[PREG->u.yx.y] = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, yx);
       GONext();
 
@@ -4397,11 +4397,11 @@ Yap_absmi(int inp)
       BEGP(pt1);
       pt1 = H;
       /* include XREG on it */
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.yx.y,Unsigned(pt1 + 1));
 #else
       YREG[PREG->u.yx.y] = Unsigned(pt1 + 1);
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, yx);
       RESET_VARIABLE(pt1);
       RESET_VARIABLE(pt1+1);
@@ -4592,7 +4592,7 @@ Yap_absmi(int inp)
       READ_IN_S();
       BEGD(d0);
       d0 = *S_SREG;
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d0 == 0)
 	d0 = (CELL)S_SREG;
 #endif
@@ -4627,7 +4627,7 @@ Yap_absmi(int inp)
       d0 = SREG[0];
       pt0 = &XREG(PREG->u.ox.x);
       PREG = NEXTOP(PREG, ox);
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d0 == 0)
 	d0 = (CELL)SREG;
 #endif
@@ -4663,7 +4663,7 @@ Yap_absmi(int inp)
       d0 = S_SREG[0];
       BEGD(d1);
       d1 = S_SREG[1];
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d0 == 0)
 	d0 = (CELL)S_SREG;
       if (d1 == 0)
@@ -4708,14 +4708,14 @@ Yap_absmi(int inp)
       d0 = S_SREG[0];
       BEGD(d1);
       d1 = S_SREG[1];
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d0 == 0)
 	XREG(PREG->u.oxx.xl) = (CELL)S_SREG;
       else
 #endif
 	XREG(PREG->u.oxx.xl) = d0;
       PREG = NEXTOP(PREG, oxx);
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d1 == 0)
 	*pt0 = (CELL)(S_SREG+1);
       else
@@ -4748,7 +4748,7 @@ Yap_absmi(int inp)
       Op(unify_y_var, oy);
       BEGD(d0);
       d0 = *SREG++;
-#if defined(SBA)
+#if defined(YAPOR_SBA)
 #ifdef FROZEN_STACKS
       if (d0 == 0) {
 	Bind_Local(YREG+PREG->u.oy.y,(CELL)(SREG-1));
@@ -4763,7 +4763,7 @@ Yap_absmi(int inp)
 #endif /* FROZEN_STACKS */
 #else
       YREG[PREG->u.oy.y] = d0;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
       PREG = NEXTOP(PREG, oy);
       GONext();
       ENDD(d0);
@@ -4772,11 +4772,11 @@ Yap_absmi(int inp)
       OpW(unify_y_var_write, oy);
       CACHE_S();
       READ_IN_S();
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.oy.y,(CELL) S_SREG);
 #else
       YREG[PREG->u.oy.y] = (CELL) S_SREG;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, oy);
       RESET_VARIABLE(S_SREG);
       WRITEBACK_S(S_SREG+1);
@@ -4787,7 +4787,7 @@ Yap_absmi(int inp)
       Op(unify_l_y_var, oy);
       BEGD(d0);
       d0 = SREG[0];
-#ifdef SBA
+#ifdef YAPOR_SBA
 #ifdef FROZEN_STACKS
       if (d0 == 0) {
 	Bind_Local(YREG+PREG->u.oy.y,(CELL)SREG);
@@ -4803,7 +4803,7 @@ Yap_absmi(int inp)
 #endif /* FROZEN_STACKS */
 #else
       YREG[PREG->u.oy.y] = d0;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
       PREG = NEXTOP(PREG, oy);
       GONext();
       ENDD(d0);
@@ -4812,11 +4812,11 @@ Yap_absmi(int inp)
       Op(unify_l_y_var_write, oy);
       CACHE_S();
       READ_IN_S();
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.oy.y,(CELL) S_SREG);
 #else
       YREG[PREG->u.oy.y] = (CELL) S_SREG;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, oy);
       RESET_VARIABLE(S_SREG);
       ENDCACHE_S();
@@ -5014,7 +5014,7 @@ Yap_absmi(int inp)
       /* we are in write mode */
       BEGD(d0);
       d0 = YREG[PREG->u.oy.y];
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d0 == 0) /* free variable */
 	*SREG++ = (CELL)(YREG+PREG->u.oy.y);
       else
@@ -5087,7 +5087,7 @@ Yap_absmi(int inp)
       /* we are in write mode */
       BEGD(d0);
       d0 = YREG[PREG->u.oy.y];
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d0 == 0) /* new variable */
 	SREG[0] = (CELL)(YREG+PREG->u.oy.y);
       else
@@ -6222,13 +6222,13 @@ Yap_absmi(int inp)
       pt0 = YREG + PREG->u.yx.y;
       XREG(PREG->u.yx.x) = (CELL) pt0;
       PREG = NEXTOP(PREG, yx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       /* We must initialise a shared variable to point to the SBA */
       if (Unsigned((Int)(pt0)-(Int)(H_FZ)) >
 	  Unsigned((Int)(B_FZ)-(Int)(H_FZ))) {
 	*pt0 =  (CELL)STACK_TO_SBA(pt0);
       } else
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	RESET_VARIABLE(pt0);
       ENDP(pt0);
       GONext();
@@ -6259,7 +6259,7 @@ Yap_absmi(int inp)
       Op(put_y_val, yx);
       BEGD(d0);
       d0 = YREG[PREG->u.yx.y];
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d0 == 0) /* new variable */
 	XREG(PREG->u.yx.x) = (CELL)(YREG+PREG->u.yx.y);
       else
@@ -6274,7 +6274,7 @@ Yap_absmi(int inp)
       ALWAYS_START_PREFETCH(yyxx);
       BEGD(d0);
       d0 = YREG[PREG->u.yyxx.y1];
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d0 == 0) /* new variable */
 	XREG(PREG->u.yyxx.x1) = (CELL)(YREG+PREG->u.yyxx.y1);
       else
@@ -6285,7 +6285,7 @@ Yap_absmi(int inp)
       PREG = NEXTOP(PREG, yyxx);
       BEGD(d1);
       d1 = YREG[PREVOP(PREG,yyxx)->u.yyxx.y2];
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d1 == 0) /* new variable */
 	XREG(PREVOP(PREG->u.yyxx,yyxx).x2) = (CELL)(YREG+PREG->u.yyxx.y2);
       else
@@ -6433,11 +6433,11 @@ Yap_absmi(int inp)
       ENDOp();
 
       Op(write_y_var, y);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.y.y,Unsigned(SREG));
 #else
       YREG[PREG->u.y.y] = Unsigned(SREG);
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, y);
       RESET_VARIABLE(SREG);
       SREG++;
@@ -6464,11 +6464,11 @@ Yap_absmi(int inp)
 
       BEGP(pt0);
       deref_body(d0, pt0, w_x_unk, w_x_bound);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       if (pt0 > H && pt0<(CELL *)B_FZ) {
 #else
       if (pt0 > H) {
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	/* local variable: let us bind it to the list */
 #ifdef FROZEN_STACKS  /* TRAIL */
 	Bind_Local(pt0, Unsigned(SREG));
@@ -6491,7 +6491,7 @@ Yap_absmi(int inp)
       Op(write_y_val, y);
       BEGD(d0);
       d0 = YREG[PREG->u.y.y];
-#ifdef SBA
+#ifdef YAPOR_SBA
       if (d0 == 0) /* new variable */
 	*SREG++ = (CELL)(YREG+PREG->u.y.y);
       else
@@ -6515,9 +6515,9 @@ Yap_absmi(int inp)
 
       derefa_body(d0, pt0, w_y_unk, w_y_bound);
       if (pt0 > H
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	  && pt0<(CELL *)B_FZ
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	  ) {
 	PREG = NEXTOP(PREG, y);
 	/* local variable: let us bind it to the list */
@@ -6684,21 +6684,21 @@ Yap_absmi(int inp)
       ENDOpW();
 
       Op(save_pair_y, oy);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.oy.y,AbsPair(SREG));
 #else
       YREG[PREG->u.oy.y] = AbsPair(SREG);
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, oy);
       GONext();
       ENDOp();
 
       OpW(save_pair_y_write, oy);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.oy.y,AbsPair(SREG));
 #else
       YREG[PREG->u.oy.y] = AbsPair(SREG);
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, oy);
       GONextW();
       ENDOpW();
@@ -6716,21 +6716,21 @@ Yap_absmi(int inp)
       ENDOpW();
 
       Op(save_appl_y, oy);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.oy.y,AbsAppl(SREG-1));
 #else
       YREG[PREG->u.oy.y] = AbsAppl(SREG - 1);
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, oy);
       GONext();
       ENDOp();
 
       OpW(save_appl_y_write, oy);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(YREG+PREG->u.oy.y,AbsAppl(SREG-1));
 #else
       YREG[PREG->u.oy.y] = AbsAppl(SREG - 1);
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       PREG = NEXTOP(PREG, oy);
       GONextW();
       ENDOpW();
@@ -6781,11 +6781,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
       { 
 	choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	if (pt1 > top_b || pt1 < (choiceptr)H) pt1 = top_b;
 #else
 	if (pt1 > top_b) pt1 = top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
       }
 #else
       if (pt1 > B) {
@@ -6931,11 +6931,11 @@ Yap_absmi(int inp)
       { 
 	choiceptr top_b = PROTECT_FROZEN_B(B);
 
-#ifdef SBA
+#ifdef YAPOR_SBA
 	if (YREG > (CELL *) top_b || YREG < H) ASP = (CELL *)top_b;
 #else
 	if (YREG > (CELL *) top_b) ASP = (CELL *)top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	else ASP = (CELL *)(((char *)YREG) +  PREG->u.Osbpp.s);
       }
 #else
@@ -6975,11 +6975,11 @@ Yap_absmi(int inp)
 	{ 
 	  choiceptr top_b = PROTECT_FROZEN_B(B);
 
-#ifdef SBA
+#ifdef YAPOR_SBA
 	  if (YREG > (CELL *) top_b || YREG < H) ASP = (CELL *)top_b;
 #else
 	  if (YREG > (CELL *) top_b) ASP = (CELL *)top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	  else ASP = YREG+E_CB;
 	}
 #else
@@ -7062,11 +7062,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
       { 
 	choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	if (YREG > (CELL *) top_b || YREG < H) ASP = (CELL *) top_b;
 #else
 	if (YREG > (CELL *) top_b) ASP = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	else ASP = (CELL *)(((char *)YREG) +  PREG->u.Osbpp.s);
       }
 #else
@@ -7118,11 +7118,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
       { 
 	choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	if (YREG > (CELL *) top_b || YREG < H) ASP = (CELL *) top_b;
 #else
 	if (YREG > (CELL *) top_b) ASP = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	else {
 	  BEGD(d0);
 	  d0 = PREG->u.slp.s;
@@ -7687,14 +7687,14 @@ Yap_absmi(int inp)
       {
 	PredEntry *pt0;
 #ifdef THREADS
-	LOCK(ThreadHandlesLock);
+	LOCK(Yap_ThreadHandlesLock);
 #endif
 	pt0 = SpyCode;
 	P_before_spy = PREG;
 	PREG = pt0->CodeOfPred;
 	/* for profiler */
 #ifdef THREADS
-	UNLOCK(ThreadHandlesLock);
+	UNLOCK(Yap_ThreadHandlesLock);
 #endif
 	save_pc();
 	CACHE_A1();
@@ -9229,11 +9229,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxx.y;
       PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -9282,11 +9282,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -9415,11 +9415,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxx.y;
       PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -9468,11 +9468,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -9601,11 +9601,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxx.y;
       PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -9654,11 +9654,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -9844,11 +9844,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxx.y;
       PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -9897,11 +9897,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -9948,11 +9948,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10082,11 +10082,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxx.y;
       PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10135,11 +10135,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10268,11 +10268,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxx.y;
       PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10321,11 +10321,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10503,11 +10503,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxx.y;
       PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10556,11 +10556,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10605,11 +10605,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10787,11 +10787,11 @@ Yap_absmi(int inp)
       }
       pt0 = YREG + PREG->u.yxx.y;
       PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10840,11 +10840,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -10887,11 +10887,11 @@ Yap_absmi(int inp)
       BEGP(pt0);
       pt0 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt0,d0);
 #else
       *pt0 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt0);
       GONext();
 
@@ -11295,7 +11295,7 @@ Yap_absmi(int inp)
 	  BEGD(d1);
 	  d1 = TrailTerm(--TR);
 	  if (IsVarTerm(d1)) {
-#if defined(SBA) && defined(YAPOR)
+#if defined(YAPOR_SBA) && defined(YAPOR)
 	    /* clean up the trail when we backtrack */
 	    if (Unsigned((Int)(d1)-(Int)(H_FZ)) >
 		Unsigned((Int)(B_FZ)-(Int)(H_FZ))) {
@@ -11743,11 +11743,11 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxx.y;
 	PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,pt0[d0]);
 #else
 	*pt1 = pt0[d0];
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
 	ENDP(pt0);
@@ -11767,11 +11767,11 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxx.y;
 	PREG = NEXTOP(PREG, yxx);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,pt0[d0-1]);
 #else
 	*pt1 = pt0[d0-1];
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	GONext();
 	ENDP(pt1);
 	ENDP(pt0);
@@ -11849,11 +11849,11 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxn.y;
 	PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,pt0[d0]);
 #else
 	*pt1 = pt0[d0];
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
 	ENDP(pt0);
@@ -11873,11 +11873,11 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxn.y;
 	PREG = NEXTOP(PREG, yxn);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,pt0[d0-1]);
 #else
 	*pt1 = pt0[d0-1];
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
 	ENDP(pt0);
@@ -12288,11 +12288,11 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxx.y;
 	PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxx),Osbpp),l);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,d0);
 #else
 	*pt1 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
       } else if ((Int)d1 > 0) {
@@ -12336,22 +12336,22 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxx.y;
 	PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxx),Osbpp),l);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,d0);
 #else
 	*pt1 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
       }	else if (d1  == 0) {
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxx.y;
 	PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxx),Osbpp),l);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,d0);
 #else
 	*pt1 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
       }	else {
@@ -12426,11 +12426,11 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxn.y;
 	PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxn),Osbpp),l);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,d0);
 #else
 	*pt1 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
       }
@@ -12475,22 +12475,22 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxn.y;
 	PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxn),Osbpp),l);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,d0);
 #else
 	*pt1 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
       }	else if (d1  == 0) {
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxn.y;
 	PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxn),Osbpp),l);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,d0);
 #else
 	*pt1 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
       }	else {
@@ -12553,11 +12553,11 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxn.y;
 	PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxn),Osbpp),l);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,d0);
 #else
 	*pt1 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
       }
@@ -12565,11 +12565,11 @@ Yap_absmi(int inp)
 	BEGP(pt1);
 	pt1 = YREG + PREG->u.yxn.y;
 	PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxn),Osbpp),l);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
 	Bind_Local(pt1,d0);
 #else
 	*pt1 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
 	ENDP(pt1);
 	GONext();
       }
@@ -12619,11 +12619,11 @@ Yap_absmi(int inp)
       BEGP(pt1);
       pt1 = YREG + PREG->u.yxn.y;
       PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxn),Osbpp),l);
-#if defined(SBA) && defined(FROZEN_STACKS)
+#if defined(YAPOR_SBA) && defined(FROZEN_STACKS)
       Bind_Local(pt1,d0);
 #else
       *pt1 = d0;
-#endif /* SBA && FROZEN_STACKS */
+#endif /* YAPOR_SBA && FROZEN_STACKS */
       ENDP(pt1);
       ENDD(d1);
       GONext();
@@ -13047,11 +13047,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
 	{ 
 	  choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	  if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
 #else
 	  if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	}
 #else
 	if (ENV_YREG > (CELL *) B) {
@@ -13131,7 +13131,7 @@ Yap_absmi(int inp)
 	  pt1 = RepAppl(d0);
 	  BEGD(d2);
 	  for (d2 = ArityOfFunctor(f); d2; d2--) {
-#ifdef SBA
+#ifdef YAPOR_SBA
 	    BEGD(d1);
 	    d1 = pt1[d2];
 	    if (d1 == 0) {
@@ -13252,11 +13252,11 @@ Yap_absmi(int inp)
 #ifdef FROZEN_STACKS
 	{ 
 	  choiceptr top_b = PROTECT_FROZEN_B(B);
-#ifdef SBA
+#ifdef YAPOR_SBA
 	  if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
 #else
 	  if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	}
 #else
 	if (ENV_YREG > (CELL *) B) {
@@ -13336,7 +13336,7 @@ Yap_absmi(int inp)
 	  pt1 = RepAppl(d0);
 	  BEGD(d2);
 	  for (d2 = ArityOfFunctor(f); d2; d2--) {
-#ifdef SBA
+#ifdef YAPOR_SBA
 	    BEGD(d1);
 	    d1 = pt1[d2];
 	    if (d1 == 0) {
@@ -13459,11 +13459,11 @@ Yap_absmi(int inp)
 	{ 
 	  choiceptr top_b = PROTECT_FROZEN_B(B);
 
-#ifdef SBA
+#ifdef YAPOR_SBA
 	  if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
 #else
 	  if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 	  else ENV_YREG = (CELL *)((CELL)ENV_YREG + ENV_Size(CPREG));
 	}
 #else
@@ -13588,7 +13588,7 @@ Yap_absmi(int inp)
 	  pt1 = RepAppl(d0);
 	  BEGD(d2);
 	  for (d2 = arity; d2; d2--) {
-#ifdef SBA
+#ifdef YAPOR_SBA
 	    BEGD(d1);
 	    d1 = pt1[d2];
 	    if (d1 == 0)
diff --git a/C/adtdefs.c b/C/adtdefs.c
index 96dcab3d3..7c637dca0 100755
--- a/C/adtdefs.c
+++ b/C/adtdefs.c
@@ -1322,7 +1322,7 @@ Yap_ArrayToList(register Term *tp, int nof)
   t = MkAtomTerm(AtomNil);
   while (pt > tp) {
     Term tm = *--pt;
-#if SBA
+#if YAPOR_SBA
     if (tm == 0)
       t = MkPairTerm((CELL)pt, t);
     else
diff --git a/C/agc.c b/C/agc.c
index 4949ff5ee..6f91934be 100755
--- a/C/agc.c
+++ b/C/agc.c
@@ -384,7 +384,7 @@ clean_atom_list(AtomHashEntry *HashPtr)
     AtomEntry *at =  RepAtom(atm);
     if (AtomResetMark(at) ||
 	at->PropsOfAE != NIL ||
-	(AGCHook != NULL && !AGCHook(atm))) {
+	(Yap_AGCHook != NULL && !Yap_AGCHook(atm))) {
       patm = &(at->NextOfAE);
       atm = at->NextOfAE;
     } else {
@@ -463,7 +463,7 @@ atom_gc(USES_REGS1)
   mark_stacks(PASS_REGS1);
   restore_codes();
   clean_atoms();
-  AGcLastCall = NOfAtoms;
+  Yap_AGcLastCall = NOfAtoms;
   YAPLeaveCriticalSection();
   agc_time = Yap_cputime()-time_start;
   tot_agc_time += agc_time;
@@ -511,7 +511,7 @@ p_agc_threshold(USES_REGS1)
 {
   Term t = Deref(ARG1);
   if (IsVarTerm(t)) {
-    return Yap_unify(ARG1, MkIntegerTerm(AGcThreshold));
+    return Yap_unify(ARG1, MkIntegerTerm(Yap_AGcThreshold));
   } else if (!IsIntegerTerm(t)) {
     Yap_Error(TYPE_ERROR_INTEGER,t,"prolog_flag/2 agc_margin");
     return FALSE;
@@ -521,7 +521,7 @@ p_agc_threshold(USES_REGS1)
       Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,t,"prolog_flag/2 agc_margin");
       return FALSE;
     } else {
-      AGcThreshold = i;
+      Yap_AGcThreshold = i;
       return TRUE;
     }
   }
diff --git a/C/alloc.c b/C/alloc.c
index 28a5d48fd..e5796a14d 100755
--- a/C/alloc.c
+++ b/C/alloc.c
@@ -704,8 +704,8 @@ AllocHeap(unsigned long int size)
 	UNLOCK(HeapTopLock);
 	Yap_signal(YAP_CDOVF_SIGNAL);
       } else {
-	if (size > SizeOfOverflow)
-	  SizeOfOverflow = size*sizeof(CELL) + sizeof(YAP_SEG_SIZE);
+	if (size > Yap_SizeOfOverflow)
+	  Yap_SizeOfOverflow = size*sizeof(CELL) + sizeof(YAP_SEG_SIZE);
 	/* big allocations, the caller must handle the problem */
 	UNLOCK(HeapUsedLock);
 	UNLOCK(HeapTopLock);
diff --git a/C/arith0.c b/C/arith0.c
index 0f83ec950..bd0a1f718 100644
--- a/C/arith0.c
+++ b/C/arith0.c
@@ -114,25 +114,25 @@ eval0(Int fi) {
   case op_heapused:
     RINT(HeapUsed);
   case op_localsp:
-#if SBA
+#if YAPOR_SBA
     RINT((Int)ASP);
 #else
     RINT(LCL0 - ASP);
 #endif
   case op_b:
-#if SBA
+#if YAPOR_SBA
     RINT((Int)B);
 #else
     RINT(LCL0 - (CELL *)B);
 #endif
   case op_env:
-#if SBA
+#if YAPOR_SBA
     RINT((Int)YENV);
 #else
     RINT(LCL0 - YENV);
 #endif
   case op_tr:
-#if SBA
+#if YAPOR_SBA
     RINT(TR);
 #else
     RINT(((CELL *)TR)-LCL0);
@@ -140,7 +140,7 @@ eval0(Int fi) {
   case op_stackfree:
     RINT(Unsigned(ASP) - Unsigned(H));
   case op_globalsp:
-#if SBA
+#if YAPOR_SBA
     RINT((Int)H);
 #else
     RINT(H - H0);
diff --git a/C/c_interface.c b/C/c_interface.c
index 406b49af0..ff897f9f1 100755
--- a/C/c_interface.c
+++ b/C/c_interface.c
@@ -2828,7 +2828,7 @@ YAP_Init(YAP_init_args *yap_init)
 #if defined(YAPOR) || defined(TABLING)
 #ifdef TABLING
     /* make sure we initialise this field */
-    GLOBAL_root_dep_fr = NULL;
+    Yap_root_dep_fr = NULL;
 #endif
     make_root_frames();
 #ifdef YAPOR
@@ -2837,13 +2837,13 @@ YAP_Init(YAP_init_args *yap_init)
     Yap_init_local();
 #ifdef YAPOR
     if (worker_id != 0) {
-#if SBA||ENV_COPY
+#if YAPOR_SBA||YAPOR_COPY
       /*
 	In the SBA we cannot just happily inherit registers
 	from the other workers
       */
       Yap_InitYaamRegs();
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 #ifndef THREADS
       Yap_InitPreAllocCodeSpace();
 #endif
@@ -3300,8 +3300,8 @@ YAP_AtomReleaseHold(Atom at)
 X_API Agc_hook
 YAP_AGCRegisterHook(Agc_hook hook)
 {
-  Agc_hook old = AGCHook;
-  AGCHook = hook;
+  Agc_hook old = Yap_AGCHook;
+  Yap_AGCHook = hook;
   return old;
 } 
 
@@ -3537,9 +3537,9 @@ YAP_SetYAPFlag(yap_flag_t flag, int val)
     return TRUE;
   case YAPC_ENABLE_AGC:
     if (val) {
-      AGcThreshold = 10000;
+      Yap_AGcThreshold = 10000;
     } else {
-      AGcThreshold = 0;
+      Yap_AGcThreshold = 0;
     }
     return TRUE;
   default:
diff --git a/C/cdmgr.c b/C/cdmgr.c
index 8519d02e3..ce34e43c6 100644
--- a/C/cdmgr.c
+++ b/C/cdmgr.c
@@ -2564,7 +2564,7 @@ init_consult(int mode, char *file)
   ConsultSp--;
   ConsultSp->c = (ConsultBase-ConsultSp);
   ConsultBase = ConsultSp;
-#if !defined(YAPOR) && !defined(SBA)
+#if !defined(YAPOR) && !defined(YAPOR_SBA)
   /*  if (consult_level == 0)
       do_toggle_static_predicates_in_use(TRUE); */
 #endif
@@ -2608,7 +2608,7 @@ end_consult( USES_REGS1 )
   ConsultSp += 3;
   consult_level--;
   LastAssertedPred = NULL;
-#if !defined(YAPOR) && !defined(SBA)
+#if !defined(YAPOR) && !defined(YAPOR_SBA)
   /*  if (consult_level == 0)
       do_toggle_static_predicates_in_use(FALSE);*/
 #endif
diff --git a/C/compiler.c b/C/compiler.c
index 93058ed93..185e51ecb 100755
--- a/C/compiler.c
+++ b/C/compiler.c
@@ -328,7 +328,7 @@ check_var(Term t, unsigned int level, Int argno, compiler_struct *cglobs) {
 
   if (IsNewVar(v)) {		/* new var */
     v = (Ventry *) Yap_AllocCMem(sizeof(*v), &cglobs->cint);
-#if SBA
+#if YAPOR_SBA
     v->SelfOfVE = 0;
 #else
     v->SelfOfVE = (CELL) v;
diff --git a/C/dbase.c b/C/dbase.c
index 26ba7a3e8..c7272fc3f 100755
--- a/C/dbase.c
+++ b/C/dbase.c
@@ -858,7 +858,7 @@ static CELL *MkDBTerm(register CELL *pt0, register CELL *pt0_end,
   deref_var:
     if (!DB_MARKED(d0)) {
       if ( 
-#if SBA
+#if YAPOR_SBA
 	  d0 != 0
 #else
 	  d0 != (CELL)ptd0
@@ -884,7 +884,7 @@ static CELL *MkDBTerm(register CELL *pt0, register CELL *pt0_end,
 	CheckDBOverflow(1);
 	/* variables need to be offset at read time */
 	*ptd0 = (CELL)StoPoint;
-#if SBA
+#if YAPOR_SBA
 	/* the copy we keep will be an empty variable   */
 	*StoPoint++ = 0;
 #else
diff --git a/C/dlmalloc.c b/C/dlmalloc.c
index 3fc74edb5..78e189d8c 100755
--- a/C/dlmalloc.c
+++ b/C/dlmalloc.c
@@ -212,8 +212,8 @@ yapsbrk(long size)
       UNLOCK(HeapTopLock);
       Yap_signal(YAP_CDOVF_SIGNAL);
     } else {
-     if (size > SizeOfOverflow)
-	SizeOfOverflow = size;
+     if (size > Yap_SizeOfOverflow)
+	Yap_SizeOfOverflow = size;
       /* big allocations, the caller must handle the problem */
       UNLOCK(HeapUsedLock);
       UNLOCK(HeapTopLock);
diff --git a/C/exec.c b/C/exec.c
index b15e2b4ea..935f35793 100644
--- a/C/exec.c
+++ b/C/exec.c
@@ -215,7 +215,7 @@ do_execute(Term t, Term mod USES_REGS)
        might skip a svar */
     pt = RepAppl(t)+1;
     for (i = 1; i <= arity; i++) {
-#if SBA
+#if YAPOR_SBA
       Term d0 = *pt++;
       if (d0 == 0)
 `	XREGS[i] = (CELL)(pt-1);
@@ -358,7 +358,7 @@ do_execute_n(Term t, Term mod, unsigned int n USES_REGS)
      otherwise I would dereference the argument and
      might skip a svar */
   for (i = 1; i <= arity-n; i++) {
-#if SBA
+#if YAPOR_SBA
     Term d0 = *pt++;
     if (d0 == 0)
       XREGS[i] = (CELL)(pt-1);
@@ -610,7 +610,7 @@ p_execute_clause( USES_REGS1 )
        might skip a svar */
     pt = RepAppl(t)+1;
     for (i = 1; i <= arity; ++i) {
-#if SBA
+#if YAPOR_SBA
 	Term d0 = *pt++;
 	if (d0 == 0)
 	  XREGS[i] = (CELL)(pt-1);
@@ -693,7 +693,7 @@ p_execute0( USES_REGS1 )
        might skip a svar */
     pt = RepAppl(t)+1;
     for (i = 1; i <= arity; ++i) {
-#if SBA
+#if YAPOR_SBA
 	Term d0 = *pt++;
 	if (d0 == 0)
 	  XREGS[i] = (CELL)(pt-1);
@@ -764,7 +764,7 @@ p_execute_nonstop( USES_REGS1 )
        might skip a svar */
     pt = RepAppl(t)+1;
     for (i = 1; i <= arity; ++i) {
-#if SBA
+#if YAPOR_SBA
 	Term d0 = *pt++;
 	if (d0 == 0)
 	  XREGS[i] = (CELL)(pt-1);
@@ -1341,7 +1341,7 @@ p_restore_regs2( USES_REGS1 )
   if (!IsIntegerTerm(d0)) {
     return(FALSE);
   }
-#if SBA
+#if YAPOR_SBA
   pt0 = (choiceptr)IntegerOfTerm(d0);
 #else
   pt0 = (choiceptr)(LCL0-IntOfTerm(d0));
@@ -1386,7 +1386,7 @@ p_clean_ifcp( USES_REGS1 ) {
     Yap_Error(TYPE_ERROR_INTEGER, t, "cut_at/1");
     return FALSE;    
   }
-#if SBA
+#if YAPOR_SBA
   pt0 = (choiceptr)IntegerOfTerm(t);
 #else
   pt0 = cp_from_integer(t PASS_REGS);
@@ -1633,9 +1633,9 @@ Yap_InitYaamRegs(void)
   STATIC_PREDICATES_MARKED = FALSE;
 #ifdef FROZEN_STACKS
   H_FZ = H;
-#ifdef SBA
+#ifdef YAPOR_SBA
   BSEG =
-#endif /* SBA */
+#endif /* YAPOR_SBA */
   BBREG = B_FZ = (choiceptr) Yap_LocalBase;
   TR = TR_FZ = (tr_fr_ptr) Yap_TrailBase;
 #endif /* FROZEN_STACKS */
diff --git a/C/grow.c b/C/grow.c
index 918a5212d..c4166c176 100755
--- a/C/grow.c
+++ b/C/grow.c
@@ -1256,10 +1256,10 @@ do_growheap(int fix_code, UInt in_size, struct intermediates *cip, tr_fr_ptr *ol
   Yap_Error(OUT_OF_HEAP_ERROR,TermNil,"cannot grow Heap: more than a worker/thread running");
   return FALSE;
 #endif
-  if (SizeOfOverflow > sz) {
+  if (Yap_SizeOfOverflow > sz) {
     if (size < YAP_ALLOC_SIZE)
       size = YAP_ALLOC_SIZE;
-    sz = AdjustPageSize(SizeOfOverflow);
+    sz = AdjustPageSize(Yap_SizeOfOverflow);
   }
   while(sz >= sizeof(CELL) * K16 && !static_growheap(sz, fix_code, cip, old_trp, tksp, vep PASS_REGS)) {
     size = size/2;
@@ -1401,7 +1401,7 @@ Yap_growheap(int fix_code, UInt in_size, void *cip)
 
   if (NOfAtoms > 2*AtomHashTableSize) {
     UInt n = NOfAtoms;
-    if (AGcThreshold)
+    if (Yap_AGcThreshold)
       Yap_atom_gc( PASS_REGS1 );
     /* check if we have a significant improvement from agc */
     if (n > NOfAtoms+ NOfAtoms/10 ||
@@ -1442,12 +1442,12 @@ Yap_growglobal(CELL **ptr)
   unsigned long sz = sizeof(CELL) * K16;
 
 #if defined(YAPOR) && !defined(THREADS)
-  if (number_workers != 1) {
+  if (Yap_number_workers != 1) {
     Yap_Error(OUT_OF_STACK_ERROR,TermNil,"cannot grow Global: more than a worker/thread running");
     return(FALSE);
   }
 #elif defined(THREADS)
-  if (NOfThreads != 1) {
+  if (Yap_NOfThreads != 1) {
     Yap_Error(OUT_OF_STACK_ERROR,TermNil,"cannot grow Global: more than a worker/thread running");
     return(FALSE);
   }
diff --git a/C/heapgc.c b/C/heapgc.c
index aba9e30f7..3a0f90371 100755
--- a/C/heapgc.c
+++ b/C/heapgc.c
@@ -929,7 +929,7 @@ init_dbtable(tr_fr_ptr trail_ptr USES_REGS) {
 #ifdef FROZEN_STACKS  /* TRAIL */
             /* avoid frozen segments */
       if (
-#ifdef SBA
+#ifdef YAPOR_SBA
 	  (ADDR) pt0 >= HeapTop
 #else
 	  (ADDR) pt0 >= Yap_TrailBase && (ADDR) pt0 < Yap_TrailTop
@@ -2499,7 +2499,7 @@ sweep_trail(choiceptr gc_B, tr_fr_ptr old_TR USES_REGS)
 #ifdef FROZEN_STACKS  /* TRAIL */
 	/* process all segments */
 	if (
-#ifdef SBA
+#ifdef YAPOR_SBA
 	    (ADDR) pt0 >= Yap_GlobalBase
 #else
 	    (ADDR) pt0 >= Yap_TrailBase
diff --git a/C/index.c b/C/index.c
index ad45f6e57..10ebf5263 100644
--- a/C/index.c
+++ b/C/index.c
@@ -839,6 +839,7 @@ sort_group(GroupDef *grp, CELL *top, struct intermediates *cint)
   base = top;
   while (top+2*max > (CELL *)Yap_TrailTop) {
     if (!Yap_growtrail(2*max*CellSize, TRUE)) {
+      Yap_Error_Size = 2*max*CellSize;
       save_machine_regs();
       siglongjmp(cint->CompilerBotch,4);
       return;
@@ -2066,6 +2067,7 @@ groups_in(ClauseDef *min, ClauseDef *max, GroupDef *grp, struct intermediates *c
       siglongjmp(cint->CompilerBotch,4);
 #else
       if (!Yap_growtrail(sz, TRUE)) {
+	Yap_Error_Size = sz;
 	save_machine_regs();
 	siglongjmp(cint->CompilerBotch,4);
 	return 0;
@@ -2194,6 +2196,7 @@ emit_switch_space(UInt n, UInt item_size, struct intermediates *cint, CELL func_
     UInt sz = sizeof(LogUpdIndex)+n*item_size;
     LogUpdIndex *cl = (LogUpdIndex *)Yap_AllocCodeSpace(sz);
     if (cl == NULL) {
+      Yap_Error_Size = sz;
       /* grow stack */
       save_machine_regs();
       siglongjmp(cint->CompilerBotch,2);
@@ -2214,6 +2217,7 @@ emit_switch_space(UInt n, UInt item_size, struct intermediates *cint, CELL func_
     UInt sz = sizeof(StaticIndex)+n*item_size;
     StaticIndex *cl = (StaticIndex *)Yap_AllocCodeSpace(sz);
     if (cl == NULL) {
+      Yap_Error_Size = sz;
       /* grow stack */
       save_machine_regs();
       siglongjmp(cint->CompilerBotch,2);
diff --git a/C/init.c b/C/init.c
index 82d8cbed6..531e46b0e 100755
--- a/C/init.c
+++ b/C/init.c
@@ -1218,9 +1218,9 @@ InitFirstWorkerThreadHandle(void)
 static void
 InitScratchPad(int wid)
 {
-  FOREIGN_WL(wid)->scratchpad.ptr = NULL;
-  FOREIGN_WL(wid)->scratchpad.sz = SCRATCH_START_SIZE;
-  FOREIGN_WL(wid)->scratchpad.msz = SCRATCH_START_SIZE;
+  FOREIGN(wid)->scratchpad.ptr = NULL;
+  FOREIGN(wid)->scratchpad.sz = SCRATCH_START_SIZE;
+  FOREIGN(wid)->scratchpad.msz = SCRATCH_START_SIZE;
 }
 
 void
@@ -1235,22 +1235,17 @@ Yap_CloseScratchPad(void)
 #include "iglobals.h"
 #include "ilocals.h"
 
-#if defined(YAPOR) || defined(THREADS)
-#define MAX_INITS MAX_AGENTS
-#else
-#define MAX_INITS 1
-#endif
 
 #if defined(YAPOR) &&  !defined(THREADS)
-struct worker_shared *Yap_global;
+struct global_data *Yap_global;
 #else
-struct worker_shared Yap_Global;
+struct global_data Yap_Global;
 #endif
 
-#if defined(YAPOR) &&  !defined(THREADS)
+#if defined(THREADS)
+struct worker_local	*Yap_WLocal[MAX_THREADS];
+#elif defined(YAPOR)
 struct worker_local	*Yap_WLocal;
-#elif defined(YAPOR) || defined(THREADS)
-struct worker_local	*Yap_WLocal[MAX_AGENTS];
 #else
 struct worker_local	Yap_WLocal;
 #endif
@@ -1261,7 +1256,7 @@ InitCodes(void)
   CACHE_REGS
 #if THREADS
   int wid;
-  for (wid = 1; wid < MAX_INITS; wid++) {
+  for (wid = 1; wid < MAX_THREADS; wid++) {
     Yap_WLocal[wid] = NULL;
   }
 #endif
@@ -1349,19 +1344,19 @@ Yap_InitWorkspace(UInt Heap, UInt Stack, UInt Trail, UInt Atts, UInt max_table_s
   worker_id = 0;
   if (n_workers > MAX_WORKERS)
     Yap_Error(INTERNAL_ERROR, TermNil, "excessive number of workers (Yap_InitWorkspace)");
-#ifdef ENV_COPY
+#ifdef YAPOR_COPY
   INFORMATION_MESSAGE("YapOr: copy model with %d worker%s", n_workers, n_workers == 1 ? "":"s");
-#elif ACOW
+#elif YAPOR_COW
   INFORMATION_MESSAGE("YapOr: acow model with %d worker%s", n_workers, n_workers == 1 ? "":"s");
-#else /* SBA */
+#else /* YAPOR_SBA */
   INFORMATION_MESSAGE("YapOr: sba model with %d worker%s", n_workers, n_workers == 1 ? "":"s");
-#endif /* ENV_COPY - ACOW - SBA */
+#endif /* YAPOR_COPY - YAPOR_COW - YAPOR_SBA */
   map_memory(Heap, Stack+Atts, Trail, n_workers);
 #else
   Yap_InitMemory (Trail, Heap, Stack+Atts);
 #endif /* YAPOR && !THREADS */
 #if defined(YAPOR) || defined(TABLING)
-  Yap_init_global(max_table_size, n_workers, sch_loop, delay_load);
+  Yap_init_optyap_global(max_table_size, n_workers, sch_loop, delay_load);
 #endif /* YAPOR || TABLING */
   Yap_AttsSize = Atts;
 
@@ -1397,10 +1392,10 @@ Yap_HaltRegisterHook (HaltHookFunc f, void * env)
     return FALSE;
   h->environment = env;
   h->hook = f;
-  LOCK(BGL);
+  LOCK(Yap_BGL);
   h->next = Yap_HaltHooks;
   Yap_HaltHooks = h;
-  UNLOCK(BGL);
+  UNLOCK(Yap_BGL);
   return TRUE;
 }
 
diff --git a/C/inlines.c b/C/inlines.c
index 7bc8cc7bf..9c0d62274 100755
--- a/C/inlines.c
+++ b/C/inlines.c
@@ -442,7 +442,7 @@ p_dif( USES_REGS1 )
       BEGD(d1);
       d1 = TrailTerm(--TR);
       if (IsVarTerm(d1)) {
-#if defined(SBA) && defined(YAPOR)
+#if defined(YAPOR_SBA) && defined(YAPOR)
 	/* clean up the trail when we backtrack */
 	if (Unsigned((Int)(d1)-(Int)(H_FZ)) >
 	    Unsigned((Int)(B_FZ)-(Int)(H_FZ))) {
@@ -767,7 +767,7 @@ p_cut_by( USES_REGS1 )
   d0 = ARG1;
   deref_head(d0, cutby_x_unk);
  cutby_x_nvar:
-#if SBA
+#if YAPOR_SBA
   if (!IsIntegerTerm(d0)) {
 #else
   if (!IsIntTerm(d0)) {
@@ -775,7 +775,7 @@ p_cut_by( USES_REGS1 )
     return(FALSE);
   }
   BEGCHO(pt0);
-#if SBA
+#if YAPOR_SBA
   pt0 = (choiceptr)IntegerOfTerm(d0);
 #else
   pt0 = (choiceptr)(LCL0-IntOfTerm(d0));
diff --git a/C/mavar.c b/C/mavar.c
index 1909c670b..6667d1da3 100644
--- a/C/mavar.c
+++ b/C/mavar.c
@@ -192,7 +192,7 @@ UpdateTimedVar(Term inv, Term new USES_REGS)
 #endif
       ) {
     /* last assignment more recent than last B */
-#if SBA
+#if YAPOR_SBA
     if (Unsigned((Int)(tv)-(Int)(H_FZ)) >
 	Unsigned((Int)(B_FZ)-(Int)(H_FZ)))
       *STACK_TO_SBA(&(tv->value)) = new;
diff --git a/C/save.c b/C/save.c
index d4dcf45d6..767b8d265 100755
--- a/C/save.c
+++ b/C/save.c
@@ -409,14 +409,14 @@ save_regs(int mode USES_REGS)
       return -1;
     if (putcellptr((CELL *)EX) < 0)
       return -1;
-#if defined(SBA) || defined(TABLING)
+#if defined(YAPOR_SBA) || defined(TABLING)
     if (putcellptr(H_FZ) < 0)
       return -1;
     if (putcellptr((CELL *)B_FZ) < 0)
       return -1;
     if (putcellptr((CELL *)TR_FZ) < 0)
       return -1;
-#endif /* SBA || TABLING */
+#endif /* YAPOR_SBA || TABLING */
   }
   if (putout(CurrentModule) < 0)
     return -1;
@@ -616,13 +616,13 @@ p_save2( USES_REGS1 )
 
   Term t;
 #if defined(YAPOR) && !defined(THREADS)
-  if (number_workers != 1) {
+  if (Yap_number_workers != 1) {
     Yap_Error(SYSTEM_ERROR,TermNil,
 	       "cannot perform save: more than a worker/thread running");
     return(FALSE);
   }
 #elif defined(THREADS)
-  if (NOfThreads != 1) {
+  if (Yap_NOfThreads != 1) {
     Yap_Error(SYSTEM_ERROR,TermNil,
 	       "cannot perform save: more than a worker/thread running");
     return(FALSE);
@@ -853,7 +853,7 @@ get_regs(int flag USES_REGS)
     EX = (struct DB_TERM *)get_cellptr();
     if (Yap_ErrorMessage)
       return -1;
-#if defined(SBA) || defined(TABLING)
+#if defined(YAPOR_SBA) || defined(TABLING)
     H_FZ = get_cellptr();
     if (Yap_ErrorMessage)
       return -1;
@@ -863,7 +863,7 @@ get_regs(int flag USES_REGS)
     TR_FZ = (tr_fr_ptr)get_cellptr();
     if (Yap_ErrorMessage)
       return -1;
-#endif /* SBA || TABLING */
+#endif /* YAPOR_SBA || TABLING */
   }
   CurrentModule = get_cell();
     if (Yap_ErrorMessage)
@@ -1795,12 +1795,12 @@ p_restore( USES_REGS1 )
 
   Term t1 = Deref(ARG1);
 #if defined(YAPOR) && !defined(THREADS)
-  if (number_workers != 1) {
+  if (Yap_number_workers != 1) {
     Yap_Error(SYSTEM_ERROR,TermNil,"cannot perform save: more than a worker/thread running");
     return(FALSE);
   }
 #elif defined(THREADS)
-  if (NOfThreads != 1) {
+  if (Yap_NOfThreads != 1) {
     Yap_Error(SYSTEM_ERROR,TermNil,"cannot perform save: more than a worker/thread running");
     return(FALSE);
   }
diff --git a/C/stdpreds.c b/C/stdpreds.c
index afceae745..f80d7059f 100755
--- a/C/stdpreds.c
+++ b/C/stdpreds.c
@@ -3832,49 +3832,49 @@ p_set_yap_flags( USES_REGS1 )
 #ifdef TABLING
   case TABLING_MODE_FLAG:
     if (value == 0) {  /* default */
-      tab_ent_ptr tab_ent = GLOBAL_root_tab_ent;
+      tab_ent_ptr tab_ent = Yap_root_tab_ent;
       while(tab_ent) {
 	TabEnt_mode(tab_ent) = TabEnt_flags(tab_ent);
 	tab_ent = TabEnt_next(tab_ent);
       }
       yap_flags[TABLING_MODE_FLAG] = 0;
     } else if (value == 1) {  /* batched */
-      tab_ent_ptr tab_ent = GLOBAL_root_tab_ent;
+      tab_ent_ptr tab_ent = Yap_root_tab_ent;
       while(tab_ent) {
 	SetMode_Batched(TabEnt_mode(tab_ent));
 	tab_ent = TabEnt_next(tab_ent);
       }
       SetMode_Batched(yap_flags[TABLING_MODE_FLAG]);
     } else if (value == 2) {  /* local */
-      tab_ent_ptr tab_ent = GLOBAL_root_tab_ent;
+      tab_ent_ptr tab_ent = Yap_root_tab_ent;
       while(tab_ent) {
 	SetMode_Local(TabEnt_mode(tab_ent));
 	tab_ent = TabEnt_next(tab_ent);
       }
       SetMode_Local(yap_flags[TABLING_MODE_FLAG]);
     } else if (value == 3) {  /* exec_answers */
-      tab_ent_ptr tab_ent = GLOBAL_root_tab_ent;
+      tab_ent_ptr tab_ent = Yap_root_tab_ent;
       while(tab_ent) {
 	SetMode_ExecAnswers(TabEnt_mode(tab_ent));
 	tab_ent = TabEnt_next(tab_ent);
       }
       SetMode_ExecAnswers(yap_flags[TABLING_MODE_FLAG]);
     } else if (value == 4) {  /* load_answers */
-      tab_ent_ptr tab_ent = GLOBAL_root_tab_ent;
+      tab_ent_ptr tab_ent = Yap_root_tab_ent;
       while(tab_ent) {
 	SetMode_LoadAnswers(TabEnt_mode(tab_ent));
 	tab_ent = TabEnt_next(tab_ent);
       }
       SetMode_LoadAnswers(yap_flags[TABLING_MODE_FLAG]);
     } else if (value == 5) {  /* local_trie */
-      tab_ent_ptr tab_ent = GLOBAL_root_tab_ent;
+      tab_ent_ptr tab_ent = Yap_root_tab_ent;
       while(tab_ent) {
 	SetMode_LocalTrie(TabEnt_mode(tab_ent));
 	tab_ent = TabEnt_next(tab_ent);
       }
       SetMode_LocalTrie(yap_flags[TABLING_MODE_FLAG]);
     } else if (value == 6) {  /* global_trie */
-      tab_ent_ptr tab_ent = GLOBAL_root_tab_ent;
+      tab_ent_ptr tab_ent = Yap_root_tab_ent;
       while(tab_ent) {
 	SetMode_GlobalTrie(TabEnt_mode(tab_ent));
 	tab_ent = TabEnt_next(tab_ent);
@@ -3913,14 +3913,14 @@ p_system_mode( USES_REGS1 )
 static Int
 p_lock_system( USES_REGS1 )
 {
-  LOCK(BGL);
+  LOCK(Yap_BGL);
   return TRUE;
 }
 
 static Int
 p_unlock_system( USES_REGS1 )
 {
-  UNLOCK(BGL);
+  UNLOCK(Yap_BGL);
   return TRUE;
 }
 
diff --git a/C/sysbits.c b/C/sysbits.c
index e28cc2c0d..08e40adea 100755
--- a/C/sysbits.c
+++ b/C/sysbits.c
@@ -1830,7 +1830,7 @@ InitSignals (void)
 #if HAVE_SIGSEGV && !defined(THREADS) 
     my_signal_info (SIGSEGV, HandleSIGSEGV);
 #endif
-#ifdef ACOW
+#ifdef YAPOR_COW
     signal(SIGCHLD, SIG_IGN);  /* avoid ghosts */ 
 #endif
   } else {
diff --git a/C/threads.c b/C/threads.c
index 5dbb4db37..2c66df70d 100755
--- a/C/threads.c
+++ b/C/threads.c
@@ -51,7 +51,7 @@ static int
 allocate_new_tid(void)
 {
   int new_worker_id = 0;
-  LOCK(ThreadHandlesLock);
+  LOCK(Yap_ThreadHandlesLock);
   while(new_worker_id < MAX_THREADS &&
 	Yap_WLocal[new_worker_id] &&
 	(FOREIGN_ThreadHandle(new_worker_id).in_use == TRUE ||
@@ -73,7 +73,7 @@ allocate_new_tid(void)
   } else {
     new_worker_id = -1;
   }
-  UNLOCK(ThreadHandlesLock);
+  UNLOCK(Yap_ThreadHandlesLock);
   return new_worker_id;  
 }
 
@@ -92,9 +92,9 @@ store_specs(int new_worker_id, UInt ssize, UInt tsize, UInt sysize, Term *tpgoal
   FOREIGN_ThreadHandle(new_worker_id).ssize = ssize;
   FOREIGN_ThreadHandle(new_worker_id).tsize = tsize;
   FOREIGN_ThreadHandle(new_worker_id).sysize = sysize;
-  FOREIGN_WL(new_worker_id)->c_input_stream = Yap_c_input_stream;
-  FOREIGN_WL(new_worker_id)->c_output_stream = Yap_c_output_stream;
-  FOREIGN_WL(new_worker_id)->c_error_stream = Yap_c_error_stream;
+  FOREIGN(new_worker_id)->c_input_stream = Yap_c_input_stream;
+  FOREIGN(new_worker_id)->c_output_stream = Yap_c_output_stream;
+  FOREIGN(new_worker_id)->c_error_stream = Yap_c_error_stream;
   pm = (ssize + tsize)*1024;
   if (!(FOREIGN_ThreadHandle(new_worker_id).stack_address = malloc(pm))) {
     return FALSE;
@@ -140,14 +140,14 @@ kill_thread_engine (int wid, int always_die)
     gl = gl->NextGE;
   }
   Yap_KillStacks(wid);
-  FOREIGN_WL(wid)->active_signals = 0L;
-  free(FOREIGN_WL(wid)->scratchpad.ptr);
+  FOREIGN(wid)->active_signals = 0L;
+  free(FOREIGN(wid)->scratchpad.ptr);
   free(FOREIGN_ThreadHandle(wid).default_yaam_regs);
   FOREIGN_ThreadHandle(wid).current_yaam_regs = NULL;
   free(FOREIGN_ThreadHandle(wid).start_of_timesp);
   free(FOREIGN_ThreadHandle(wid).last_timep);
   Yap_FreeCodeSpace((ADDR)FOREIGN_ThreadHandle(wid).texit);
-  LOCK(ThreadHandlesLock);
+  LOCK(Yap_ThreadHandlesLock);
   if (FOREIGN_ThreadHandle(wid).tdetach == MkAtomTerm(AtomTrue) ||
       always_die) {
     FOREIGN_ThreadHandle(wid).zombie = FALSE;
@@ -155,7 +155,7 @@ kill_thread_engine (int wid, int always_die)
     DEBUG_TLOCK_ACCESS(1, wid);
     pthread_mutex_unlock(&(FOREIGN_ThreadHandle(wid).tlock));
   }
-  UNLOCK(ThreadHandlesLock);
+  UNLOCK(Yap_ThreadHandlesLock);
 }
 
 static void
@@ -163,7 +163,7 @@ thread_die(int wid, int always_die)
 {
   if (!always_die) {
     /* called by thread itself */
-    ThreadsTotalTime += Yap_cputime();
+    Yap_ThreadsTotalTime += Yap_cputime();
   }
   kill_thread_engine(wid, always_die);
 }
@@ -194,7 +194,7 @@ setup_engine(int myworker_id, int init_thread)
 #endif
   Yap_ReleasePreAllocCodeSpace(Yap_PreAllocCodeSpace());
   /* I exist */
-  NOfThreadsCreated++;
+  Yap_NOfThreadsCreated++;
   DEBUG_TLOCK_ACCESS(2, myworker_id);
   pthread_mutex_unlock(&(FOREIGN_ThreadHandle(myworker_id).tlock));  
 }
@@ -487,17 +487,17 @@ p_thread_join( USES_REGS1 )
 {
   Int tid = IntegerOfTerm(Deref(ARG1));
 
-  LOCK(ThreadHandlesLock);
+  LOCK(Yap_ThreadHandlesLock);
   if (!FOREIGN_ThreadHandle(tid).in_use &&
       !FOREIGN_ThreadHandle(tid).zombie) {
-    UNLOCK(ThreadHandlesLock);
+    UNLOCK(Yap_ThreadHandlesLock);
     return FALSE;
   }
   if (!FOREIGN_ThreadHandle(tid).tdetach == MkAtomTerm(AtomTrue)) {
-    UNLOCK(ThreadHandlesLock);
+    UNLOCK(Yap_ThreadHandlesLock);
     return FALSE;
   }
-  UNLOCK(ThreadHandlesLock);
+  UNLOCK(Yap_ThreadHandlesLock);
   /* make sure this lock is accessible */
   if (pthread_join(FOREIGN_ThreadHandle(tid).pthread_handle, NULL) < 0) {
     /* ERROR */
@@ -512,12 +512,12 @@ p_thread_destroy( USES_REGS1 )
 {
   Int tid = IntegerOfTerm(Deref(ARG1));
 
-  LOCK(ThreadHandlesLock);
+  LOCK(Yap_ThreadHandlesLock);
   FOREIGN_ThreadHandle(tid).zombie = FALSE;
   FOREIGN_ThreadHandle(tid).in_use = FALSE;
   DEBUG_TLOCK_ACCESS(32, tid);
   pthread_mutex_unlock(&(FOREIGN_ThreadHandle(tid).tlock));
-  UNLOCK(ThreadHandlesLock);
+  UNLOCK(Yap_ThreadHandlesLock);
   return TRUE;
 }
 
@@ -753,16 +753,16 @@ p_thread_stacks( USES_REGS1 )
   Int tid = IntegerOfTerm(Deref(ARG1));
   Int status= TRUE;
 
-  LOCK(ThreadHandlesLock);
+  LOCK(Yap_ThreadHandlesLock);
   if (!FOREIGN_ThreadHandle(tid).in_use &&
       !FOREIGN_ThreadHandle(tid).zombie) {
-    UNLOCK(ThreadHandlesLock);
+    UNLOCK(Yap_ThreadHandlesLock);
     return FALSE;
   }
   status &= Yap_unify(ARG2,MkIntegerTerm(FOREIGN_ThreadHandle(tid).ssize));
   status &= Yap_unify(ARG3,MkIntegerTerm(FOREIGN_ThreadHandle(tid).tsize));
   status &= Yap_unify(ARG4,MkIntegerTerm(FOREIGN_ThreadHandle(tid).sysize));
-  UNLOCK(ThreadHandlesLock);
+  UNLOCK(Yap_ThreadHandlesLock);
   return status;
 }
 
@@ -814,11 +814,11 @@ p_thread_signal( USES_REGS1 )
     pthread_mutex_unlock(&(FOREIGN_ThreadHandle(wid).tlock));
    return TRUE;
   }
-  LOCK(FOREIGN_WL(wid)->signal_lock);
+  LOCK(FOREIGN(wid)->signal_lock);
   FOREIGN_ThreadHandle(wid).current_yaam_regs->CreepFlag_ = 
     Unsigned(FOREIGN_ThreadHandle(wid).current_yaam_regs->LCL0_);
-  FOREIGN_WL(wid)->active_signals |= YAP_ITI_SIGNAL;
-  UNLOCK(FOREIGN_WL(wid)->signal_lock);
+  FOREIGN(wid)->active_signals |= YAP_ITI_SIGNAL;
+  UNLOCK(FOREIGN(wid)->signal_lock);
   DEBUG_TLOCK_ACCESS(18, wid);
   pthread_mutex_unlock(&(FOREIGN_ThreadHandle(wid).tlock));
   return TRUE;
@@ -834,13 +834,13 @@ static Int
 p_nof_threads( USES_REGS1 )
 {				/* '$nof_threads'(+P)	 */
   int i = 0, wid;
-  LOCK(ThreadHandlesLock);
+  LOCK(Yap_ThreadHandlesLock);
   for (wid = 0; wid < MAX_THREADS; wid++) {
     if (!Yap_WLocal[wid]) break;
     if (FOREIGN_ThreadHandle(wid).in_use)
       i++;
   }
-  UNLOCK(ThreadHandlesLock);
+  UNLOCK(Yap_ThreadHandlesLock);
   return Yap_unify(ARG1,MkIntegerTerm(i));
 }
 
@@ -859,13 +859,13 @@ p_max_threads( USES_REGS1 )
 static Int 
 p_nof_threads_created( USES_REGS1 )
 {				/* '$nof_threads'(+P)	 */
-  return Yap_unify(ARG1,MkIntTerm(NOfThreadsCreated));
+  return Yap_unify(ARG1,MkIntTerm(Yap_NOfThreadsCreated));
 }
 
 static Int 
 p_thread_runtime( USES_REGS1 )
 {				/* '$thread_runtime'(+P)	 */
-  return Yap_unify(ARG1,MkIntegerTerm(ThreadsTotalTime));
+  return Yap_unify(ARG1,MkIntegerTerm(Yap_ThreadsTotalTime));
 }
 
 static Int 
diff --git a/H/Regs.h b/H/Regs.h
index 11edc98ea..b2401ce36 100644
--- a/H/Regs.h
+++ b/H/Regs.h
@@ -90,9 +90,9 @@ typedef struct regstore_t
     Int     CurSlot_;
     CELL    CreepFlag_;		/* 13                                         */
     CELL   *HB_;		/* 4 heap (global) stack top at latest c.p.   */
-#if defined(SBA) || defined(TABLING)
+#if defined(YAPOR_SBA) || defined(TABLING)
     choiceptr BB_;		/* 4 local stack top at latest c.p.   */
-#endif /* SBA || TABLING */
+#endif /* YAPOR_SBA || TABLING */
     CELL  *H0_;			/* 2 base of heap (global) stack              */
     tr_fr_ptr TR_;		/* 24 top of trail                            */
     CELL   *H_;			/* 25 top of heap (global)  stack             */
@@ -119,24 +119,24 @@ typedef struct regstore_t
 /* visualc*/
     struct DB_TERM   * EX_;     /* 18                                         */
     Term  CurrentModule_;
-#if defined(SBA) || defined(TABLING)
+#if defined(YAPOR_SBA) || defined(TABLING)
     CELL *H_FZ_;
     choiceptr B_FZ_;
     tr_fr_ptr TR_FZ_;
-#endif /* SBA || TABLING */
+#endif /* YAPOR_SBA || TABLING */
     struct pred_entry *PP_;
 #if defined(YAPOR) || defined(THREADS)
     /* recursive write-locks for PredEntry */
     yamop **PREG_ADDR_;
     unsigned int worker_id_;
-#ifdef SBA
+#ifdef YAPOR_SBA
     choiceptr BSEG_;
     struct or_frame *frame_head_, *frame_tail_;
     char *binding_array_;
     int  sba_offset_;
     int  sba_end_;
     int  sba_size_;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 #endif /* YAPOR || THREADS */
 #if (defined(YAPOR) || defined(TABLING))
     struct local_data *LOCAL_;
@@ -635,16 +635,16 @@ EXTERN inline void restore_B(void) {
 #define	AuxTop        Yap_REGS.AuxTop_
 #define EX            Yap_REGS.EX_
 #define DEPTH	      Yap_REGS.DEPTH_
-#if defined(SBA) || defined(TABLING)
+#if defined(YAPOR_SBA) || defined(TABLING)
 #define H_FZ          Yap_REGS.H_FZ_
 #define B_FZ          Yap_REGS.B_FZ_
 #define TR_FZ         Yap_REGS.TR_FZ_
-#endif /* SBA || TABLING */
+#endif /* YAPOR_SBA || TABLING */
 #define PP	         (Yap_REGS.PP_)
 #if defined(YAPOR) || defined(THREADS)
 #define worker_id         (Yap_REGS.worker_id_)
 #define PREG_ADDR	         (Yap_REGS.PREG_ADDR_)
-#ifdef SBA
+#ifdef YAPOR_SBA
 #define BSEG	      Yap_REGS.BSEG_
 #define binding_array Yap_REGS.binding_array_
 #define sba_offset    Yap_REGS.sba_offset_
@@ -652,7 +652,7 @@ EXTERN inline void restore_B(void) {
 #define sba_size      Yap_REGS.sba_size_
 #define frame_head    Yap_REGS.frame_head_
 #define frame_tail    Yap_REGS.frame_tail_
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 #endif /* YAPOR */
 #if defined(YAPOR) || defined(TABLING)
 #define LOCAL	      Yap_REGS.LOCAL_
@@ -686,10 +686,10 @@ EXTERN inline void restore_B(void) {
 
 #define HBREG HB
 
-#if defined(SBA) || defined(TABLING)
+#if defined(YAPOR_SBA) || defined(TABLING)
 #define BB            Yap_REGS.BB_
 #define BBREG         BB
-#endif /* SBA || TABLING */
+#endif /* YAPOR_SBA || TABLING */
 
 #if !defined(THREADS)
 /* use actual addresses for regs */
diff --git a/H/Yap.h b/H/Yap.h
index aa53b9235..9d320f73f 100755
--- a/H/Yap.h
+++ b/H/Yap.h
@@ -17,7 +17,7 @@
 #define YAP_H 1
 
 #include "config.h"
-#if defined(ENV_COPY) || defined(TABLING) || defined(THREADS)
+#if defined(YAPOR_COPY) || defined(TABLING) || defined(THREADS)
 #include "opt.config.h"
 #endif /* YAPOR || TABLING */
 
@@ -39,24 +39,24 @@
 #error Do not explicitly define YAPOR
 #endif /* YAPOR */
 
-#if (defined(ENV_COPY) && (defined(ACOW) || defined(SBA))) || (defined(ACOW) && defined(SBA))
+#if (defined(YAPOR_COPY) && (defined(YAPOR_COW) || defined(YAPOR_SBA))) || (defined(YAPOR_COW) && defined(YAPOR_SBA))
 #error Do not define multiple or-parallel models
-#endif /* (ENV_COPY && (ACOW || SBA)) || (ACOW && SBA) */
+#endif /* (YAPOR_COPY && (YAPOR_COW || YAPOR_SBA)) || (YAPOR_COW && YAPOR_SBA) */
 
-#if defined(ENV_COPY) || defined(ACOW) || defined(SBA) || defined(THREADS)
+#if defined(YAPOR_COPY) || defined(YAPOR_COW) || defined(YAPOR_SBA) || defined(THREADS)
 #define YAPOR 1
-#endif /* ENV_COPY || ACOW || SBA */
+#endif /* YAPOR_COPY || YAPOR_COW || YAPOR_SBA */
 
-#if defined(TABLING) && (defined(ACOW) || defined(SBA))
-#error Currently TABLING only works with ENV_COPY
-#endif /* TABLING && (ACOW || SBA) */
+#if defined(TABLING) && (defined(YAPOR_COW) || defined(YAPOR_SBA))
+#error Currently TABLING only works with YAPOR_COPY
+#endif /* TABLING && (YAPOR_COW || YAPOR_SBA) */
 
 #ifdef YAPOR
 #define FIXED_STACKS 1
 #ifdef THREADS
-#undef ACOW
-#undef SBA
-#undef ENV_COPY
+#undef YAPOR_COW
+#undef YAPOR_SBA
+#undef YAPOR_COPY
 #endif
 #endif /* YAPOR */
 
@@ -80,9 +80,9 @@
 #define USE_SYSTEM_MALLOC 1
 #endif
 
-#if defined(TABLING) || defined(SBA)
+#if defined(TABLING) || defined(YAPOR_YAPOR_SBA)
 #define FROZEN_STACKS 1
-#endif /* TABLING || SBA */
+#endif /* TABLING || YAPOR_YAPOR_SBA */
 
 #ifdef _MSC_VER			/* Microsoft's Visual C++ Compiler */
 /* adjust a config.h from mingw32 to work with vc++ */
@@ -428,11 +428,6 @@ typedef pthread_rwlock_t rwlock_t;
 #ifdef __alpha
 #include <locks_alpha_funcs.h>
 #endif
-#if defined(THREADS)
-#define MAX_AGENTS MAX_THREADS
-#elif defined(YAPOR)
-#define MAX_AGENTS MAX_WORKERS
-#endif
 #endif
 
 /************ variables	concerned with Error Handling *************/
@@ -732,7 +727,7 @@ typedef enum
 #else
 
 #if !GC_NO_TAGS
-#if defined(SBA) && defined(__linux__)
+#if defined(YAPOR_SBA) && defined(__linux__)
 #define MBIT     /* 0x20000000 */ MKTAG(0x1,0)	/* mark bit */
 #else
 #define RBIT     /* 0x20000000 */ MKTAG(0x1,0)	/* relocation chain bit */
@@ -829,7 +824,7 @@ VarOfTerm (Term t)
 }
 
 
-#ifdef SBA
+#ifdef YAPOR_SBA
 
 inline EXTERN Term MkVarTerm__ ( USES_REGS1 );
 
@@ -1065,8 +1060,8 @@ IntegerOfTerm (Term t)
 
 /*************** unification routines ***********************************/
 
-#ifdef SBA
-#include "or.sbaamiops.h"
+#ifdef YAPOR_SBA
+#include "or.sba_amiops.h"
 #else
 #include "amiops.h"
 #endif
@@ -1212,9 +1207,9 @@ extern int Yap_PrologShouldHandleInterrupts;
 #ifdef YAPOR
 #define YAPEnterCriticalSection()                                        \
 	{                                                                \
-          if (worker_id != GLOBAL_LOCKS_who_locked_heap) {               \
-	    LOCK(GLOBAL_LOCKS_heap_access);                              \
-	    GLOBAL_LOCKS_who_locked_heap = worker_id;                    \
+          if (worker_id != Yap_locks_who_locked_heap) {               \
+	    LOCK(Yap_locks_heap_access);                              \
+	    Yap_locks_who_locked_heap = worker_id;                    \
 	  }                                                              \
           Yap_PrologMode |= CritMode;                                   \
           Yap_CritLocks++;                                              \
@@ -1232,8 +1227,8 @@ extern int Yap_PrologShouldHandleInterrupts;
 	      Yap_PrologMode &= ~AbortMode;                             \
 	      Yap_Error(PURE_ABORT, 0, "");                             \
             }                                                            \
-	    GLOBAL_LOCKS_who_locked_heap = MAX_WORKERS;                  \
-            UNLOCK(GLOBAL_LOCKS_heap_access);                            \
+	    Yap_locks_who_locked_heap = MAX_WORKERS;                  \
+            UNLOCK(Yap_locks_heap_access);                            \
           }                                                              \
         }
 #elif defined(THREADS)
@@ -1304,8 +1299,8 @@ extern char emacs_tmp[], emacs_tmp2[];
 #include "opt.macros.h"
 #endif /* YAPOR || TABLING */
 
-#ifdef SBA
-#include "or.sbaunify.h"
+#ifdef YAPOR_SBA
+#include "or.sba_unify.h"
 #endif
 
 /********* execution mode ***********************/
diff --git a/H/YapHeap.h b/H/YapHeap.h
index bf4bf2e8d..7425b3ddd 100755
--- a/H/YapHeap.h
+++ b/H/YapHeap.h
@@ -181,26 +181,26 @@ typedef struct various_codes {
 #include "hlocals.h"
 
 #if defined(YAPOR) && !defined(THREADS)
-extern struct worker_shared *Yap_global;
+extern struct global_data *Yap_global;
 #else
-extern struct worker_shared Yap_Global;
+extern struct global_data Yap_Global;
 #define Yap_global (&Yap_Global)
 #endif
 
 #if defined(YAPOR) || defined(THREADS)
 #if defined(THREADS)
-extern struct worker_local	*Yap_WLocal[MAX_AGENTS];
+extern struct worker_local	*Yap_WLocal[MAX_THREADS];
 #define WL (Yap_WLocal[worker_id])
-#define FOREIGN_WL(wid) (Yap_WLocal[(wid)])
+#define FOREIGN(wid) (Yap_WLocal[(wid)])
 #else
 extern struct worker_local	*Yap_WLocal;
 #define WL (Yap_WLocal+worker_id)
-#define FOREIGN_WL(wid) (Yap_WLocal+wid)
+#define FOREIGN(wid) (Yap_WLocal+wid)
 #endif
 #else
 extern struct worker_local	Yap_WLocal;
 #define WL (&Yap_WLocal)
-#define FOREIGN_WL(wid) (&Yap_WLocal)
+#define FOREIGN(wid) (&Yap_WLocal)
 #endif
 
 
diff --git a/H/absmi.h b/H/absmi.h
index 30938481f..fd34bcb55 100644
--- a/H/absmi.h
+++ b/H/absmi.h
@@ -690,13 +690,13 @@ Macros to check the limits of stacks
 
 #endif
 
-#if (defined(SBA) && defined(YAPOR)) || defined(TABLING)
+#if (defined(YAPOR_SBA) && defined(YAPOR)) || defined(TABLING)
 #define check_stack(Label, GLOB)                             \
  if ( (Int)(Unsigned(YOUNGEST_CP((choiceptr)ENV_YREG,B_FZ)) - Unsigned(YOUNGEST_H(H_FZ,GLOB))) < CreepFlag  ) goto Label
 #else
 #define check_stack(Label, GLOB)                             \
  if ( (Int)(Unsigned(ENV_YREG) - Unsigned(GLOB)) < CreepFlag ) goto Label
-#endif /* SBA && YAPOR */
+#endif /* YAPOR_SBA && YAPOR */
 
 /***************************************************************
 * Macros for choice point manipulation                         *
@@ -813,7 +813,7 @@ Macros to check the limits of stacks
 
 
 #ifdef FROZEN_STACKS
-#ifdef SBA
+#ifdef YAPOR_SBA
 #define PROTECT_FROZEN_H(CPTR)                                  \
        ((Unsigned((Int)((CPTR)->cp_h)-(Int)(H_FZ)) <            \
 	 Unsigned((Int)(B_FZ)-(Int)(H_FZ))) ?                   \
@@ -830,7 +830,7 @@ Macros to check the limits of stacks
 #else /* TABLING */
 #define PROTECT_FROZEN_B(CPTR)  (YOUNGER_CP(CPTR, B_FZ) ? CPTR        : B_FZ)
 #define PROTECT_FROZEN_H(CPTR)  (((CPTR)->cp_h > H_FZ) ? (CPTR)->cp_h : H_FZ)
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 #else
 #define PROTECT_FROZEN_B(CPTR)  (CPTR)
 #define PROTECT_FROZEN_H(CPTR)  (CPTR)->cp_h
diff --git a/H/amidefs.h b/H/amidefs.h
index 8f467e1dc..13a09dd22 100644
--- a/H/amidefs.h
+++ b/H/amidefs.h
@@ -66,7 +66,7 @@
 #endif 
 
 #ifdef FROZEN_STACKS
-#ifdef SBA
+#ifdef YAPOR_SBA
 #define PROTECT_FROZEN_H(CPTR)                                  \
        ((Unsigned((Int)((CPTR)->cp_h)-(Int)(H_FZ)) <            \
 	 Unsigned((Int)(B_FZ)-(Int)(H_FZ))) ?                   \
@@ -83,7 +83,7 @@
 #else /* TABLING */
 #define PROTECT_FROZEN_B(CPTR)  (YOUNGER_CP(CPTR, B_FZ) ? CPTR        : B_FZ)
 #define PROTECT_FROZEN_H(CPTR)  (((CPTR)->cp_h > H_FZ) ? (CPTR)->cp_h : H_FZ)
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 #else
 #define PROTECT_FROZEN_B(CPTR)  (CPTR)
 #define PROTECT_FROZEN_H(CPTR)  (CPTR)->cp_h
@@ -875,7 +875,7 @@ typedef yamop yamopp;
 
 #define PREVOP(V,TYPE)    ((yamop *)((CODEADDR)(V)-(CELL)NEXTOP((yamop *)NULL,TYPE)))
 
-#if defined(TABLING) || defined(SBA)
+#if defined(TABLING) || defined(YAPOR_SBA)
 typedef struct trail_frame {
   Term term;
   CELL value;
@@ -888,7 +888,7 @@ typedef Term *tr_fr_ptr;
 
 #define TrailTerm(X)   (*(X))
 #define TrailVal(X)    OOOOOOPS: this program should not compile
-#endif /* TABLING || SBA  */
+#endif /* TABLING || YAPOR_SBA  */
 
 
 /*
@@ -978,7 +978,7 @@ typedef struct choicept {
 #define SHOULD_CUT_UP_TO(X,Y)  ((X) != (Y))
 /* #define SHOULD_CUT_UP_TO(X,Y)  ((X)  (Y)) */
 
-#ifdef SBA
+#ifdef YAPOR_SBA
 #define SHARED_CP(CP)  ((CP) >= B_FZ || (CP) < (choiceptr)H_FZ)
 
 #define YOUNGER_CP(CP1, CP2)						\
@@ -998,13 +998,13 @@ typedef struct choicept {
 #define YOUNGER_H(H1, H2) FIXMEE!!!!
 
 
-#else /* ENV_COPY || ACOW */
+#else /* YAPOR_COPY || YAPOR_COW */
 #define YOUNGER_CP(CP1, CP2)           ((CP1) <  (CP2))
 #define EQUAL_OR_YOUNGER_CP(CP1, CP2)  ((CP1) <= (CP2))
 
 #define YOUNGER_H(H1, H2)           ((CELL *)(H1) > (CELL *)(H2))
 
-#endif /* SBA */
+#endif /* YAPOR_SBA */
 
 #define YOUNGEST_CP(CP1, CP2)           (YOUNGER_CP(CP1,CP2) ? (CP1) : (CP2))
 
diff --git a/H/dglobals.h b/H/dglobals.h
index bf8ad9351..ffdeca415 100644
--- a/H/dglobals.h
+++ b/H/dglobals.h
@@ -24,39 +24,34 @@
 
 #if THREADS
 
-#define NOfThreads Yap_global->n_of_threads
+#define Yap_NOfThreads Yap_global->n_of_threads
 
-#define NOfThreadsCreated Yap_global->n_of_threads_created
+#define Yap_NOfThreadsCreated Yap_global->n_of_threads_created
 
-#define ThreadsTotalTime Yap_global->threads_total_time
+#define Yap_ThreadsTotalTime Yap_global->threads_total_time
 #endif
 
 #if defined(YAPOR) || defined(THREADS)
 
-#define BGL Yap_global->bgl
+#define Yap_BGL Yap_global->bgl
 #endif
 
 #define Yap_AllowLocalExpansion Yap_global->allow_local_expansion
 #define Yap_AllowGlobalExpansion Yap_global->allow_global_expansion
 #define Yap_AllowTrailExpansion Yap_global->allow_trail_expansion
-#define SizeOfOverflow Yap_global->size_of_overflow
+#define Yap_SizeOfOverflow Yap_global->size_of_overflow
 
-#define AGcLastCall Yap_global->agc_last_call
+#define Yap_AGcLastCall Yap_global->agc_last_call
 
-#define AGcThreshold Yap_global->agc_threshold
-#define AGCHook Yap_global->agc_hook
-
-#if HAVE_LIBREADLINE
-#define ReadlineBuf Yap_global->readline_buf
-#define ReadlinePos Yap_global->readline_pos
-#endif
+#define Yap_AGcThreshold Yap_global->agc_threshold
+#define Yap_AGCHook Yap_global->agc_hook
 
 #ifdef THREADS
-#define ThreadHandlesLock Yap_global->thread_handles_lock
+#define Yap_ThreadHandlesLock Yap_global->thread_handles_lock
 #endif 
 
 #if defined(YAPOR) || defined(TABLING)
-#define GLOBAL Yap_global->global
+#define Yap_optyap_data Yap_global->optyap_data
 #define REMOTE Yap_global->remote
 #endif
 
diff --git a/H/dlocals.h b/H/dlocals.h
index 9440b46db..d54c27e45 100644
--- a/H/dlocals.h
+++ b/H/dlocals.h
@@ -98,7 +98,7 @@
 #if GC_NO_TAGS
 #define Yap_bp WL->b_p
 #endif
-#if defined(TABLING) || defined(SBA)
+#if defined(TABLING) || defined(YAPOR_SBA)
 #define sTR WL->wl_sTR
 #define sTR0 WL->wl_sTR0
 #define new_TR WL->new_tr
diff --git a/H/hglobals.h b/H/hglobals.h
index a3c7beb12..8401b2f53 100644
--- a/H/hglobals.h
+++ b/H/hglobals.h
@@ -20,7 +20,7 @@
 
 
 
-typedef struct worker_shared {
+typedef struct global_data {
 
 #if THREADS
 
@@ -46,17 +46,12 @@ typedef struct worker_shared {
   UInt  agc_threshold;
   Agc_hook  agc_hook;
 
-#if HAVE_LIBREADLINE
-  char  *readline_buf;
-  char  *readline_pos;
-#endif
-
 #ifdef THREADS
   lockvar  thread_handles_lock;
 #endif 
 
 #if defined(YAPOR) || defined(TABLING)
-  struct global_data  global;
+  struct optyap_global_data  optyap_data;
   struct local_data  remote[MAX_WORKERS];
 #endif
 
diff --git a/H/hlocals.h b/H/hlocals.h
index 9ebc4c711..60880e3e5 100644
--- a/H/hlocals.h
+++ b/H/hlocals.h
@@ -100,7 +100,7 @@ typedef struct worker_local {
 #if GC_NO_TAGS
   char*  b_p;
 #endif
-#if defined(TABLING) || defined(SBA)
+#if defined(TABLING) || defined(YAPOR_SBA)
   struct trail_frame*  wl_sTR;
   struct trail_frame*  wl_sTR0;
   struct trail_frame*  new_tr;
diff --git a/H/iglobals.h b/H/iglobals.h
index da2c57d70..18789bf6e 100644
--- a/H/iglobals.h
+++ b/H/iglobals.h
@@ -46,11 +46,6 @@ static void InitGlobal(void) {
   Yap_global->agc_threshold = 10000;
   Yap_global->agc_hook = NULL;
 
-#if HAVE_LIBREADLINE
-  Yap_global->readline_buf = NULL;
-  Yap_global->readline_pos = 0L;
-#endif
-
 #ifdef THREADS
   INIT_LOCK(Yap_global->thread_handles_lock);
 #endif 
diff --git a/H/ilocals.h b/H/ilocals.h
index c2481740c..f765279c7 100644
--- a/H/ilocals.h
+++ b/H/ilocals.h
@@ -5,134 +5,134 @@
 
 static void InitWorker(int wid) {
 
-  FOREIGN_WL(wid)->c_input_stream = 0;
-  FOREIGN_WL(wid)->c_output_stream = 1;
-  FOREIGN_WL(wid)->c_error_stream = 2;
+  FOREIGN(wid)->c_input_stream = 0;
+  FOREIGN(wid)->c_output_stream = 1;
+  FOREIGN(wid)->c_error_stream = 2;
 
-  FOREIGN_WL(wid)->rinfo.old_ASP = NULL;
-  FOREIGN_WL(wid)->rinfo.old_LCL0 = NULL;
-  FOREIGN_WL(wid)->rinfo.old_TR = NULL;
-  FOREIGN_WL(wid)->rinfo.old_GlobalBase = NULL;
-  FOREIGN_WL(wid)->rinfo.old_H = NULL;
-  FOREIGN_WL(wid)->rinfo.old_H0 = NULL;
-  FOREIGN_WL(wid)->rinfo.old_TrailBase = NULL;
-  FOREIGN_WL(wid)->rinfo.old_TrailTop = NULL;
-  FOREIGN_WL(wid)->rinfo.old_HeapBase = NULL;
-  FOREIGN_WL(wid)->rinfo.old_HeapTop = NULL;
-  FOREIGN_WL(wid)->rinfo.cl_diff = 0L;
-  FOREIGN_WL(wid)->rinfo.g_diff = 0L;
-  FOREIGN_WL(wid)->rinfo.h_diff = 0L;
-  FOREIGN_WL(wid)->rinfo.g_diff0 = 0L;
-  FOREIGN_WL(wid)->rinfo.g_split = NULL;
-  FOREIGN_WL(wid)->rinfo.l_diff = 0L;
-  FOREIGN_WL(wid)->rinfo.tr_diff = 0L;
-  FOREIGN_WL(wid)->rinfo.x_diff = 0L;
-  FOREIGN_WL(wid)->rinfo.delay_diff = 0L;
-  FOREIGN_WL(wid)->rinfo.base_diff = 0L;
-  FOREIGN_WL(wid)->call_counters.reductions = 0L;
-  FOREIGN_WL(wid)->call_counters.reductions_retries = 0L;
-  FOREIGN_WL(wid)->call_counters.retries = 0L;
-  FOREIGN_WL(wid)->call_counters.reductions_on = 0L;
-  FOREIGN_WL(wid)->call_counters.reductions_retries_on = 0L;
-  FOREIGN_WL(wid)->call_counters.retries_on = 0L;
-  FOREIGN_WL(wid)->interrupts_disabled = FALSE;
+  FOREIGN(wid)->rinfo.old_ASP = NULL;
+  FOREIGN(wid)->rinfo.old_LCL0 = NULL;
+  FOREIGN(wid)->rinfo.old_TR = NULL;
+  FOREIGN(wid)->rinfo.old_GlobalBase = NULL;
+  FOREIGN(wid)->rinfo.old_H = NULL;
+  FOREIGN(wid)->rinfo.old_H0 = NULL;
+  FOREIGN(wid)->rinfo.old_TrailBase = NULL;
+  FOREIGN(wid)->rinfo.old_TrailTop = NULL;
+  FOREIGN(wid)->rinfo.old_HeapBase = NULL;
+  FOREIGN(wid)->rinfo.old_HeapTop = NULL;
+  FOREIGN(wid)->rinfo.cl_diff = 0L;
+  FOREIGN(wid)->rinfo.g_diff = 0L;
+  FOREIGN(wid)->rinfo.h_diff = 0L;
+  FOREIGN(wid)->rinfo.g_diff0 = 0L;
+  FOREIGN(wid)->rinfo.g_split = NULL;
+  FOREIGN(wid)->rinfo.l_diff = 0L;
+  FOREIGN(wid)->rinfo.tr_diff = 0L;
+  FOREIGN(wid)->rinfo.x_diff = 0L;
+  FOREIGN(wid)->rinfo.delay_diff = 0L;
+  FOREIGN(wid)->rinfo.base_diff = 0L;
+  FOREIGN(wid)->call_counters.reductions = 0L;
+  FOREIGN(wid)->call_counters.reductions_retries = 0L;
+  FOREIGN(wid)->call_counters.retries = 0L;
+  FOREIGN(wid)->call_counters.reductions_on = 0L;
+  FOREIGN(wid)->call_counters.reductions_retries_on = 0L;
+  FOREIGN(wid)->call_counters.retries_on = 0L;
+  FOREIGN(wid)->interrupts_disabled = FALSE;
 
 
-  FOREIGN_WL(wid)->consultsp = NULL;
+  FOREIGN(wid)->consultsp = NULL;
 
 
 
-  FOREIGN_WL(wid)->consultbase = NULL;
+  FOREIGN(wid)->consultbase = NULL;
 
-  FOREIGN_WL(wid)->consultlow = NULL;
+  FOREIGN(wid)->consultlow = NULL;
 
-  FOREIGN_WL(wid)->global_arena = 0L;
-  FOREIGN_WL(wid)->global_arena_overflows = 0L;
-  FOREIGN_WL(wid)->delay_arena_overflows = 0L;
-  FOREIGN_WL(wid)->arena_overflows = 0L;
-  FOREIGN_WL(wid)->depth_arenas = 0;
-  FOREIGN_WL(wid)->arith_error = FALSE;
-  FOREIGN_WL(wid)->last_asserted_pred = NULL;
-  FOREIGN_WL(wid)->debug_on = FALSE;
-  FOREIGN_WL(wid)->f_info = NULL;
-  FOREIGN_WL(wid)->scanner_stack = NULL;
-  FOREIGN_WL(wid)->scanner_extra_blocks = NULL;
-  FOREIGN_WL(wid)->ball_term = NULL;
-  FOREIGN_WL(wid)->active_signals = 0L;
-  FOREIGN_WL(wid)->i_pred_arity = 0L;
-  FOREIGN_WL(wid)->prof_end = NULL;
-  FOREIGN_WL(wid)->uncaught_throw = FALSE;
-  FOREIGN_WL(wid)->doing_undefp = FALSE;
-  FOREIGN_WL(wid)->start_line = 0L;
+  FOREIGN(wid)->global_arena = 0L;
+  FOREIGN(wid)->global_arena_overflows = 0L;
+  FOREIGN(wid)->delay_arena_overflows = 0L;
+  FOREIGN(wid)->arena_overflows = 0L;
+  FOREIGN(wid)->depth_arenas = 0;
+  FOREIGN(wid)->arith_error = FALSE;
+  FOREIGN(wid)->last_asserted_pred = NULL;
+  FOREIGN(wid)->debug_on = FALSE;
+  FOREIGN(wid)->f_info = NULL;
+  FOREIGN(wid)->scanner_stack = NULL;
+  FOREIGN(wid)->scanner_extra_blocks = NULL;
+  FOREIGN(wid)->ball_term = NULL;
+  FOREIGN(wid)->active_signals = 0L;
+  FOREIGN(wid)->i_pred_arity = 0L;
+  FOREIGN(wid)->prof_end = NULL;
+  FOREIGN(wid)->uncaught_throw = FALSE;
+  FOREIGN(wid)->doing_undefp = FALSE;
+  FOREIGN(wid)->start_line = 0L;
   InitScratchPad(wid);
 #ifdef  COROUTINING
-  FOREIGN_WL(wid)->woken_goals = 0L;
-  FOREIGN_WL(wid)->atts_mutable_list = 0L;
+  FOREIGN(wid)->woken_goals = 0L;
+  FOREIGN(wid)->atts_mutable_list = 0L;
 #endif
 
-  FOREIGN_WL(wid)->gc_generation = 0L;
-  FOREIGN_WL(wid)->gc_phase = 0L;
-  FOREIGN_WL(wid)->gc_current_phase = 0L;
-  FOREIGN_WL(wid)->gc_calls = 0L;
-  FOREIGN_WL(wid)->tot_gc_time = 0L;
-  FOREIGN_WL(wid)->tot_gc_recovered = 0L;
-  FOREIGN_WL(wid)->last_gc_time = 0L;
-  FOREIGN_WL(wid)->last_ss_time = 0L;
+  FOREIGN(wid)->gc_generation = 0L;
+  FOREIGN(wid)->gc_phase = 0L;
+  FOREIGN(wid)->gc_current_phase = 0L;
+  FOREIGN(wid)->gc_calls = 0L;
+  FOREIGN(wid)->tot_gc_time = 0L;
+  FOREIGN(wid)->tot_gc_recovered = 0L;
+  FOREIGN(wid)->last_gc_time = 0L;
+  FOREIGN(wid)->last_ss_time = 0L;
 #if LOW_LEVEL_TRACER
-  FOREIGN_WL(wid)->total_cps = 0;
+  FOREIGN(wid)->total_cps = 0;
 #endif
 
 #if defined(YAPOR) || defined(THREADS)
-  INIT_LOCK(FOREIGN_WL(wid)->signal_lock);
-  FOREIGN_WL(wid)->wpp = NULL;
+  INIT_LOCK(FOREIGN(wid)->signal_lock);
+  FOREIGN(wid)->wpp = NULL;
 
-  FOREIGN_WL(wid)->tot_marked = 0L;
-  FOREIGN_WL(wid)->tot_oldies = 0L;
+  FOREIGN(wid)->tot_marked = 0L;
+  FOREIGN(wid)->tot_oldies = 0L;
 #if DEBUG && COROUTINING
-  FOREIGN_WL(wid)->tot_smarked = 0L;
+  FOREIGN(wid)->tot_smarked = 0L;
 #endif
-  FOREIGN_WL(wid)->wl_current_B = NULL;
-  FOREIGN_WL(wid)->wl_prev_HB = NULL;
-  FOREIGN_WL(wid)->hgen = NULL;
-  FOREIGN_WL(wid)->ip_top = NULL;
+  FOREIGN(wid)->wl_current_B = NULL;
+  FOREIGN(wid)->wl_prev_HB = NULL;
+  FOREIGN(wid)->hgen = NULL;
+  FOREIGN(wid)->ip_top = NULL;
 #if GC_NO_TAGS
-  FOREIGN_WL(wid)->b_p = NULL;
+  FOREIGN(wid)->b_p = NULL;
 #endif
-#if defined(TABLING) || defined(SBA)
-  FOREIGN_WL(wid)->wl_sTR = NULL;
-  FOREIGN_WL(wid)->wl_sTR0 = NULL;
-  FOREIGN_WL(wid)->new_tr = NULL;
+#if defined(TABLING) || defined(YAPOR_SBA)
+  FOREIGN(wid)->wl_sTR = NULL;
+  FOREIGN(wid)->wl_sTR0 = NULL;
+  FOREIGN(wid)->new_tr = NULL;
 #else
-  FOREIGN_WL(wid)->wl_sTR = NULL;
-  FOREIGN_WL(wid)->wl_sTR0 = NULL;
-  FOREIGN_WL(wid)->new_tr = NULL;
+  FOREIGN(wid)->wl_sTR = NULL;
+  FOREIGN(wid)->wl_sTR0 = NULL;
+  FOREIGN(wid)->new_tr = NULL;
 #endif
-  FOREIGN_WL(wid)->conttop0 = NULL;
-  FOREIGN_WL(wid)->conttop = NULL;
-  FOREIGN_WL(wid)->disc_trail_entries = 0;
+  FOREIGN(wid)->conttop0 = NULL;
+  FOREIGN(wid)->conttop = NULL;
+  FOREIGN(wid)->disc_trail_entries = 0;
 
-  FOREIGN_WL(wid)->Gc_ma_h_top = NULL;
-  FOREIGN_WL(wid)->Gc_ma_h_list = NULL;
-  FOREIGN_WL(wid)->Gc_timestamp = 0L;
-  FOREIGN_WL(wid)->DB_vec = NULL;
-  FOREIGN_WL(wid)->DB_vec0 = NULL;
-  FOREIGN_WL(wid)->DB_root = NULL;
-  FOREIGN_WL(wid)->DB_nil = NULL;
+  FOREIGN(wid)->Gc_ma_h_top = NULL;
+  FOREIGN(wid)->Gc_ma_h_list = NULL;
+  FOREIGN(wid)->Gc_timestamp = 0L;
+  FOREIGN(wid)->DB_vec = NULL;
+  FOREIGN(wid)->DB_vec0 = NULL;
+  FOREIGN(wid)->DB_root = NULL;
+  FOREIGN(wid)->DB_nil = NULL;
 #endif /* defined(YAPOR) || defined(THREADS) */
 
-  FOREIGN_WL(wid)->dynamic_arrays = NULL;
-  FOREIGN_WL(wid)->static_arrays = NULL;
-  FOREIGN_WL(wid)->global_variables = NULL;
-  FOREIGN_WL(wid)->allow_restart = FALSE;
+  FOREIGN(wid)->dynamic_arrays = NULL;
+  FOREIGN(wid)->static_arrays = NULL;
+  FOREIGN(wid)->global_variables = NULL;
+  FOREIGN(wid)->allow_restart = FALSE;
 
-  FOREIGN_WL(wid)->cmem_first_block = NULL;
-  FOREIGN_WL(wid)->cmem_first_block_sz = 0L;
+  FOREIGN(wid)->cmem_first_block = NULL;
+  FOREIGN(wid)->cmem_first_block_sz = 0L;
 
-  FOREIGN_WL(wid)->label_first_array = NULL;
-  FOREIGN_WL(wid)->label_first_array_sz = 0L;
+  FOREIGN(wid)->label_first_array = NULL;
+  FOREIGN(wid)->label_first_array_sz = 0L;
 
-  FOREIGN_WL(wid)->Yap_ld_ = Yap_InitThreadIO(wid);
-  FOREIGN_WL(wid)->_execution = NULL;
+  FOREIGN(wid)->Yap_ld_ = Yap_InitThreadIO(wid);
+  FOREIGN(wid)->_execution = NULL;
 
 #if (defined(YAPOR) || defined(TABLING)) && defined(THREADS)
 
diff --git a/H/rglobals.h b/H/rglobals.h
index 72c08757f..c7bdffff9 100644
--- a/H/rglobals.h
+++ b/H/rglobals.h
@@ -46,11 +46,6 @@ static void RestoreGlobal(void) {
 
 
 
-#if HAVE_LIBREADLINE
-
-
-#endif
-
 #ifdef THREADS
   REINIT_LOCK(Yap_global->thread_handles_lock);
 #endif 
diff --git a/H/rlocals.h b/H/rlocals.h
index 2ef9e5720..444a29b04 100644
--- a/H/rlocals.h
+++ b/H/rlocals.h
@@ -46,7 +46,7 @@ static void RestoreWorker(int wid USES_REGS) {
 
 
 
-  FOREIGN_WL(wid)->global_arena = TermToGlobalOrAtomAdjust(FOREIGN_WL(wid)->global_arena);
+  FOREIGN(wid)->global_arena = TermToGlobalOrAtomAdjust(FOREIGN(wid)->global_arena);
 
 
 
@@ -66,12 +66,12 @@ static void RestoreWorker(int wid USES_REGS) {
 
 
 #ifdef  COROUTINING
-  FOREIGN_WL(wid)->woken_goals = TermToGlobalAdjust(FOREIGN_WL(wid)->woken_goals);
-  FOREIGN_WL(wid)->atts_mutable_list = TermToGlobalAdjust(FOREIGN_WL(wid)->atts_mutable_list);
+  FOREIGN(wid)->woken_goals = TermToGlobalAdjust(FOREIGN(wid)->woken_goals);
+  FOREIGN(wid)->atts_mutable_list = TermToGlobalAdjust(FOREIGN(wid)->atts_mutable_list);
 #endif
 
-  FOREIGN_WL(wid)->gc_generation = TermToGlobalAdjust(FOREIGN_WL(wid)->gc_generation);
-  FOREIGN_WL(wid)->gc_phase = TermToGlobalAdjust(FOREIGN_WL(wid)->gc_phase);
+  FOREIGN(wid)->gc_generation = TermToGlobalAdjust(FOREIGN(wid)->gc_generation);
+  FOREIGN(wid)->gc_phase = TermToGlobalAdjust(FOREIGN(wid)->gc_phase);
 
 
 
@@ -83,7 +83,7 @@ static void RestoreWorker(int wid USES_REGS) {
 #endif
 
 #if defined(YAPOR) || defined(THREADS)
-  REINIT_LOCK(FOREIGN_WL(wid)->signal_lock);
+  REINIT_LOCK(FOREIGN(wid)->signal_lock);
 
 
 
@@ -98,7 +98,7 @@ static void RestoreWorker(int wid USES_REGS) {
 #if GC_NO_TAGS
 
 #endif
-#if defined(TABLING) || defined(SBA)
+#if defined(TABLING) || defined(YAPOR_SBA)
 
 
 
@@ -120,9 +120,9 @@ static void RestoreWorker(int wid USES_REGS) {
 
 #endif /* defined(YAPOR) || defined(THREADS) */
 
-  FOREIGN_WL(wid)->dynamic_arrays = PtoArrayEAdjust(FOREIGN_WL(wid)->dynamic_arrays);
-  FOREIGN_WL(wid)->static_arrays = PtoArraySAdjust(FOREIGN_WL(wid)->static_arrays);
-  FOREIGN_WL(wid)->global_variables = PtoGlobalEAdjust(FOREIGN_WL(wid)->global_variables);
+  FOREIGN(wid)->dynamic_arrays = PtoArrayEAdjust(FOREIGN(wid)->dynamic_arrays);
+  FOREIGN(wid)->static_arrays = PtoArraySAdjust(FOREIGN(wid)->static_arrays);
+  FOREIGN(wid)->global_variables = PtoGlobalEAdjust(FOREIGN(wid)->global_variables);
 
 
 
diff --git a/INSTALL b/INSTALL
index 1014c8124..08e27fcc0 100644
--- a/INSTALL
+++ b/INSTALL
@@ -62,7 +62,7 @@ quality:
 
   o -DYAPOR gives or-parallelism in Muse style. If you add -DSBA to it
 you will have the Sparse Binding Array instead of copying. If you add
--DACOW instead you will have the \alphaCOW model, that is, forking
+-DYAPOR_COW instead you will have the \alphaCOW model, that is, forking
 instead of copying.
 
 1.3 Porting Yap
diff --git a/Makefile.in b/Makefile.in
index 67a20ae78..e2a4d3ecb 100755
--- a/Makefile.in
+++ b/Makefile.in
@@ -42,9 +42,9 @@ DOCSDIR=$(SHAREDIR)/doc/Yap
 #
 # very experimental stuff, you'll need to contact the developers
 # if you want to use this:
-#       -DENV_COPY: or-parallelism with environment copying, in Muse style.
-#       -DSBA: or-parallelism with sparse binding arrays.
-#       -DACOW: or-parallelism with copy-on-write.
+#       -DYAPOR_COPY: or-parallelism with environment copying, in Muse style.
+#       -DYAPOR_SBA: or-parallelism with sparse binding arrays.
+#       -DYAPOR_COW: or-parallelism with copy-on-write.
 #       -DTABLING: support for tabling
 #
 #
@@ -187,7 +187,7 @@ HEADERS = \
 	$(srcdir)/OPTYap/opt.config.h \
 	$(srcdir)/OPTYap/opt.proto.h $(srcdir)/OPTYap/opt.structs.h \
 	$(srcdir)/OPTYap/opt.macros.h $(srcdir)/OPTYap/or.macros.h \
-	$(srcdir)/OPTYap/or.sbaamiops.h $(srcdir)/OPTYap/or.sbaunify.h \
+	$(srcdir)/OPTYap/or.sba_amiops.h $(srcdir)/OPTYap/or.sba_unify.h \
 	$(srcdir)/OPTYap/tab.structs.h $(srcdir)/OPTYap/locks_x86.h \
 	$(srcdir)/OPTYap/locks_sparc.h $(srcdir)/OPTYap/locks_mips.h \
 	$(srcdir)/OPTYap/locks_mips_funcs.h $(srcdir)/OPTYap/locks_alpha.h \
@@ -261,9 +261,9 @@ C_SOURCES= \
 	$(srcdir)/BEAM/eamindex.c $(srcdir)/BEAM/eamamasm.c \
 	$(srcdir)/BEAM/eam_gc.c $(srcdir)/BEAM/eam_split.c \
 	$(srcdir)/OPTYap/opt.memory.c $(srcdir)/OPTYap/opt.init.c \
-	$(srcdir)/OPTYap/opt.preds.c $(srcdir)/OPTYap/or.engine.c \
-	$(srcdir)/OPTYap/or.cowengine.c $(srcdir)/OPTYap/or.sbaengine.c \
-	$(srcdir)/OPTYap/or.threadengine.c \
+	$(srcdir)/OPTYap/opt.preds.c $(srcdir)/OPTYap/or.copy_engine.c \
+	$(srcdir)/OPTYap/or.cow_engine.c $(srcdir)/OPTYap/or.sba_engine.c \
+	$(srcdir)/OPTYap/or.thread_engine.c \
 	$(srcdir)/OPTYap/or.scheduler.c $(srcdir)/OPTYap/or.cut.c \
 	$(srcdir)/OPTYap/tab.tries.c $(srcdir)/OPTYap/tab.completion.c \
 	$(srcdir)/library/mpi/mpi.c $(srcdir)/library/mpi/mpe.c \
@@ -378,7 +378,7 @@ C_INTERFACE_OBJECTS = \
 
 OR_OBJECTS = \
 	opt.memory.o opt.init.o opt.preds.o   \
-	or.engine.o or.cowengine.o or.sbaengine.o or.threadengine.o \
+	or.copy_engine.o or.cow_engine.o or.sba_engine.o or.thread_engine.o \
 	or.scheduler.o or.cut.o      \
 	tab.tries.o tab.completion.o
 
@@ -500,17 +500,17 @@ opt.preds.o: $(srcdir)/OPTYap/opt.preds.c config.h
 or.cut.o: $(srcdir)/OPTYap/or.cut.c config.h
 	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.cut.c -o $@
 
-or.engine.o: $(srcdir)/OPTYap/or.engine.c config.h
-	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.engine.c -o $@
+or.copy_engine.o: $(srcdir)/OPTYap/or.copy_engine.c config.h
+	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.copy_engine.c -o $@
 
-or.cowengine.o: $(srcdir)/OPTYap/or.cowengine.c config.h
-	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.cowengine.c -o $@
+or.cow_engine.o: $(srcdir)/OPTYap/or.cow_engine.c config.h
+	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.cow_engine.c -o $@
 
-or.sbaengine.o: $(srcdir)/OPTYap/or.sbaengine.c config.h
-	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.sbaengine.c -o $@
+or.sba_engine.o: $(srcdir)/OPTYap/or.sba_engine.c config.h
+	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.sba_engine.c -o $@
 
-or.threadengine.o: $(srcdir)/OPTYap/or.threadengine.c config.h
-	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.threadengine.c -o $@
+or.thread_engine.o: $(srcdir)/OPTYap/or.thread_engine.c config.h
+	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.thread_engine.c -o $@
 
 or.scheduler.o: $(srcdir)/OPTYap/or.scheduler.c config.h
 	$(CC) -c $(CFLAGS) $(srcdir)/OPTYap/or.scheduler.c -o $@
diff --git a/OPTYap/opt.init.c b/OPTYap/opt.init.c
index c9e7b2e07..6bfdbc290 100644
--- a/OPTYap/opt.init.c
+++ b/OPTYap/opt.init.c
@@ -28,19 +28,19 @@
 #ifdef TABLING
 #include "tab.macros.h"
 #endif /* TABLING */
-#if defined(TABLING) || !defined(ACOW)
+#if defined(TABLING) || !defined(YAPOR_COW)
 #ifndef TABLING
 #include "opt.mavar.h"
 #endif /* !TABLING */
 #ifdef MULTI_ASSIGNMENT_VARIABLES
 ma_hash_entry Yap_ma_hash_table[MAVARS_HASH_SIZE];
-UInt Yap_timestamp;    /* an unsigned int */
+UInt Yap_ma_timestamp;    /* an unsigned int */
 ma_h_inner_struct *Yap_ma_h_top;
 #endif /* MULTI_ASSIGNMENT_VARIABLES */
-#endif /* TABLING || !ACOW */
-#ifdef ACOW
+#endif /* TABLING || !YAPOR_COW */
+#ifdef YAPOR_COW
 #include "sys/wait.h"
-#endif /* ACOW */
+#endif /* YAPOR_COW */
 
 
 
@@ -78,99 +78,99 @@ struct worker WORKER;
 **      Global functions      **
 *******************************/
 
-void Yap_init_global(int max_table_size, int n_workers, int sch_loop, int delay_load) {
+void Yap_init_optyap_global(int max_table_size, int n_workers, int sch_loop, int delay_load) {
   int i;
 
   /* global data related to memory management */
 #ifdef LIMIT_TABLING
   if (max_table_size)
-    GLOBAL_MAX_PAGES = ((max_table_size - 1) * 1024 * 1024 / SHMMAX + 1) * SHMMAX / Yap_page_size;
+    Yap_max_pages = ((max_table_size - 1) * 1024 * 1024 / SHMMAX + 1) * SHMMAX / Yap_page_size;
   else
-    GLOBAL_MAX_PAGES = -1;
+    Yap_max_pages = -1;
 #endif /* LIMIT_TABLING */
-  INIT_PAGES(GLOBAL_PAGES_void, void *);      
+  INIT_PAGES(Yap_pages_void, void *);      
 #ifdef YAPOR
-  INIT_PAGES(GLOBAL_PAGES_or_fr, struct or_frame);
-  INIT_PAGES(GLOBAL_PAGES_qg_sol_fr, struct query_goal_solution_frame);
-  INIT_PAGES(GLOBAL_PAGES_qg_ans_fr, struct query_goal_answer_frame);
+  INIT_PAGES(Yap_pages_or_fr , struct or_frame);
+  INIT_PAGES(Yap_pages_qg_sol_fr , struct query_goal_solution_frame);
+  INIT_PAGES(Yap_pages_qg_ans_fr, struct query_goal_answer_frame);
 #endif /* YAPOR */
 #ifdef TABLING_INNER_CUTS
-  INIT_PAGES(GLOBAL_PAGES_tg_sol_fr, struct table_subgoal_solution_frame);
-  INIT_PAGES(GLOBAL_PAGES_tg_ans_fr, struct table_subgoal_answer_frame);
+  INIT_PAGES(Yap_pages_tg_sol_fr, struct table_subgoal_solution_frame);
+  INIT_PAGES(Yap_pages_tg_ans_fr, struct table_subgoal_answer_frame);
 #endif /* TABLING_INNER_CUTS */
 #ifdef TABLING
-  INIT_PAGES(GLOBAL_PAGES_tab_ent, struct table_entry);
-  INIT_PAGES(GLOBAL_PAGES_sg_fr, struct subgoal_frame);
-  INIT_PAGES(GLOBAL_PAGES_dep_fr, struct dependency_frame);
-  INIT_PAGES(GLOBAL_PAGES_sg_node, struct subgoal_trie_node);
-  INIT_PAGES(GLOBAL_PAGES_ans_node, struct answer_trie_node);
-  INIT_PAGES(GLOBAL_PAGES_gt_node, struct global_trie_node);
-  INIT_PAGES(GLOBAL_PAGES_sg_hash, struct subgoal_trie_hash);
-  INIT_PAGES(GLOBAL_PAGES_ans_hash, struct answer_trie_hash);
-  INIT_PAGES(GLOBAL_PAGES_gt_hash, struct global_trie_hash);
+  INIT_PAGES(Yap_pages_tab_ent, struct table_entry);
+  INIT_PAGES(Yap_pages_sg_fr, struct subgoal_frame);
+  INIT_PAGES(Yap_pages_dep_fr, struct dependency_frame);
+  INIT_PAGES(Yap_pages_sg_node, struct subgoal_trie_node);
+  INIT_PAGES(Yap_pages_ans_node, struct answer_trie_node);
+  INIT_PAGES(Yap_pages_gt_node, struct global_trie_node);
+  INIT_PAGES(Yap_pages_sg_hash, struct subgoal_trie_hash);
+  INIT_PAGES(Yap_pages_ans_hash, struct answer_trie_hash);
+  INIT_PAGES(Yap_pages_gt_hash, struct global_trie_hash);
 #endif /* TABLING */
 #if defined(YAPOR) && defined(TABLING)
-  INIT_PAGES(GLOBAL_PAGES_susp_fr, struct suspension_frame);
+  INIT_PAGES(Yap_pages_susp_fr, struct suspension_frame);
 #endif /* YAPOR && TABLING */
 
 #ifdef YAPOR
   /* global static data */
-  number_workers = n_workers;
-  worker_pid(0) = getpid();
-  for (i = 1; i < number_workers; i++) worker_pid(i) = 0;
-  SCHEDULER_LOOP = sch_loop;
-  DELAYED_RELEASE_LOAD = delay_load;
+  Yap_number_workers= n_workers;
+  Yap_worker_pid(0) = getpid();
+  for (i = 1; i < Yap_number_workers; i++) Yap_worker_pid(i) = 0;
+  Yap_scheduler_loop = sch_loop;
+  Yap_delayed_release_load = delay_load;
 
   /* global data related to or-performance */
-  GLOBAL_number_goals = 0;
-  GLOBAL_best_times(0) = 0;
-  GLOBAL_performance_mode = PERFORMANCE_OFF;
+  Yap_number_goals = 0;
+  Yap_best_times(0) = 0;
+  Yap_performance_mode = PERFORMANCE_OFF;
 
   /* global data related to or-parallelism */
-  BITMAP_clear(GLOBAL_bm_present_workers);
-  for (i = 0; i < number_workers; i++) 
-    BITMAP_insert(GLOBAL_bm_present_workers, i);
-  BITMAP_copy(GLOBAL_bm_idle_workers, GLOBAL_bm_present_workers);
-  BITMAP_clear(GLOBAL_bm_root_cp_workers);
-  BITMAP_clear(GLOBAL_bm_invisible_workers);
-  BITMAP_clear(GLOBAL_bm_requestable_workers);
-  BITMAP_clear(GLOBAL_bm_executing_workers);
-  BITMAP_copy(GLOBAL_bm_finished_workers, GLOBAL_bm_present_workers);
-  INIT_LOCK(GLOBAL_LOCKS_bm_idle_workers);
-  INIT_LOCK(GLOBAL_LOCKS_bm_root_cp_workers);
-  INIT_LOCK(GLOBAL_LOCKS_bm_invisible_workers);
-  INIT_LOCK(GLOBAL_LOCKS_bm_requestable_workers);
-  INIT_LOCK(GLOBAL_LOCKS_bm_executing_workers);
-  INIT_LOCK(GLOBAL_LOCKS_bm_finished_workers);
+  BITMAP_clear(Yap_bm_present_workers);
+  for (i = 0; i < Yap_number_workers; i++) 
+    BITMAP_insert(Yap_bm_present_workers, i);
+  BITMAP_copy(Yap_bm_idle_workers, Yap_bm_present_workers);
+  BITMAP_clear(Yap_bm_root_cp_workers);
+  BITMAP_clear(Yap_bm_invisible_workers);
+  BITMAP_clear(Yap_bm_requestable_workers);
+  BITMAP_clear(Yap_bm_executing_workers);
+  BITMAP_copy(Yap_bm_finished_workers, Yap_bm_present_workers);
+  INIT_LOCK(Yap_locks_bm_idle_workers);
+  INIT_LOCK(Yap_locks_bm_root_cp_workers);
+  INIT_LOCK(Yap_locks_bm_invisible_workers);
+  INIT_LOCK(Yap_locks_bm_requestable_workers);
+  INIT_LOCK(Yap_locks_bm_executing_workers);
+  INIT_LOCK(Yap_locks_bm_finished_workers);
 #ifdef TABLING_INNER_CUTS
-  INIT_LOCK(GLOBAL_LOCKS_bm_pruning_workers);
+  INIT_LOCK(Yap_locks_bm_pruning_workers);
 #endif /* TABLING_INNER_CUTS */
-  GLOBAL_LOCKS_who_locked_heap = MAX_WORKERS;
-  INIT_LOCK(GLOBAL_LOCKS_heap_access);
-  INIT_LOCK(GLOBAL_LOCKS_alloc_block);
-  if (number_workers == 1)
-    PARALLEL_EXECUTION_MODE = FALSE;
+  Yap_locks_who_locked_heap = MAX_WORKERS;
+  INIT_LOCK(Yap_locks_heap_access);
+  INIT_LOCK(Yap_locks_alloc_block);
+  if (Yap_number_workers== 1)
+    Yap_parallel_execution_mode = FALSE;
   else
-    PARALLEL_EXECUTION_MODE = TRUE;
+    Yap_parallel_execution_mode = TRUE;
 #endif /* YAPOR */
 
 #ifdef TABLING
   /* global data related to tabling */
-  new_global_trie_node(GLOBAL_root_gt, 0, NULL, NULL, NULL);
-  GLOBAL_root_tab_ent = NULL;
+  new_global_trie_node(Yap_root_gt, 0, NULL, NULL, NULL);
+  Yap_root_tab_ent = NULL;
 #ifdef LIMIT_TABLING
-  GLOBAL_first_sg_fr = NULL;
-  GLOBAL_last_sg_fr = NULL;
-  GLOBAL_check_sg_fr = NULL;
+  Yap_first_sg_fr = NULL;
+  Yap_last_sg_fr = NULL;
+  Yap_check_sg_fr = NULL;
 #endif /* LIMIT_TABLING */
-  GLOBAL_root_dep_fr = NULL;
+  Yap_root_dep_fr = NULL;
   for (i = 0; i < MAX_TABLE_VARS; i++) {
-    CELL *pt = GLOBAL_table_var_enumerator_addr(i);
+    CELL *pt = Yap_table_var_enumerator_addr(i);
     RESET_VARIABLE(pt);
   }
 #ifdef TABLE_LOCK_AT_WRITE_LEVEL
   for (i = 0; i < TABLE_LOCK_BUCKETS; i++)
-    INIT_LOCK(GLOBAL_table_lock(i));
+    INIT_LOCK(Yap_table_lock(i));
 #endif /* TABLE_LOCK_AT_WRITE_LEVEL */
 #endif /* TABLING */
 
@@ -184,13 +184,13 @@ void Yap_init_local(void) {
   /* local data related to or-parallelism */
   LOCAL = REMOTE + worker_id;
   Set_LOCAL_top_cp((choiceptr) Yap_LocalBase);
-  LOCAL_top_or_fr = GLOBAL_root_or_fr;
+  LOCAL_top_or_fr = Yap_root_or_fr;
   LOCAL_load = 0;
   LOCAL_share_request = MAX_WORKERS;
   LOCAL_reply_signal = worker_ready;
-#ifdef ENV_COPY
+#ifdef YAPOR_COPY
   INIT_LOCK(LOCAL_lock_signals);
-#endif /* ENV_COPY */
+#endif /* YAPOR_COPY */
   Set_LOCAL_prune_request(NULL);
 #endif /* YAPOR */
   INIT_LOCK(LOCAL_lock);
@@ -198,10 +198,10 @@ void Yap_init_local(void) {
   /* local data related to tabling */
   LOCAL_next_free_ans_node = NULL;
   LOCAL_top_sg_fr = NULL; 
-  LOCAL_top_dep_fr = GLOBAL_root_dep_fr; 
+  LOCAL_top_dep_fr = Yap_root_dep_fr; 
 #ifdef YAPOR
   Set_LOCAL_top_cp_on_stack((choiceptr) Yap_LocalBase); /* ??? */
-  LOCAL_top_susp_or_fr = GLOBAL_root_or_fr;
+  LOCAL_top_susp_or_fr = Yap_root_or_fr;
 #endif /* YAPOR */
 #endif /* TABLING */
   return;
@@ -217,7 +217,7 @@ void make_root_frames(void) {
   ALLOC_OR_FRAME(or_fr);   
   INIT_LOCK(OrFr_lock(or_fr));
   OrFr_alternative(or_fr) = NULL;
-  BITMAP_copy(OrFr_members(or_fr), GLOBAL_bm_present_workers);
+  BITMAP_copy(OrFr_members(or_fr), Yap_bm_present_workers);
   SetOrFr_node(or_fr, (choiceptr) Yap_LocalBase);
   OrFr_nearest_livenode(or_fr) = NULL;
   OrFr_depth(or_fr) = 0;
@@ -228,21 +228,21 @@ void make_root_frames(void) {
   OrFr_tg_solutions(or_fr) = NULL;
 #endif /* TABLING_INNER_CUTS */
 #ifdef TABLING
-  OrFr_owners(or_fr) = number_workers;
+  OrFr_owners(or_fr) = Yap_number_workers;
   OrFr_next_on_stack(or_fr) = NULL;
   OrFr_suspensions(or_fr) = NULL;
   OrFr_nearest_suspnode(or_fr) = or_fr;
 #endif /* TABLING */
   OrFr_next(or_fr) = NULL;
-  GLOBAL_root_or_fr = or_fr;
+  Yap_root_or_fr = or_fr;
 #endif /* YAPOR */
 
 #ifdef TABLING
   /* root dependency frame */
-  if (!GLOBAL_root_dep_fr) {
-    new_dependency_frame(GLOBAL_root_dep_fr, FALSE, NULL, NULL, NULL, NULL, NULL);
+  if (!Yap_root_dep_fr) {
+    new_dependency_frame(Yap_root_dep_fr, FALSE, NULL, NULL, NULL, NULL, NULL);
 #ifdef TABLING
-    DepFr_cons_cp(GLOBAL_root_dep_fr) = B;
+    DepFr_cons_cp(Yap_root_dep_fr) = B;
 #endif /* TABLING */
   }
 #endif /* TABLING */
@@ -255,8 +255,8 @@ void init_workers(void) {
 #ifdef THREADS
   return;
 #endif
-#ifdef ACOW
-  if (number_workers > 1) {
+#ifdef YAPOR_COW
+  if (Yap_number_workers> 1) {
     int son;
     son = fork();
     if (son == -1)
@@ -265,17 +265,17 @@ void init_workers(void) {
       /* I am the father, I must stay here and wait for my children to all die */
       struct sigaction sigact;
 
-      GLOBAL_master_worker = getpid();
+      Yap_master_worker = getpid();
       sigact.sa_handler = SIG_DFL;
       sigemptyset(&sigact.sa_mask);
       sigact.sa_flags = SA_RESTART;
       sigaction(SIGINT, &sigact, NULL);
       pause();
       exit(0);
-    } else worker_pid(0) = getpid();
+    } else Yap_worker_pid(0) = getpid();
   }
-#endif /* ACOW */
-  for (proc = 1; proc < number_workers; proc++) {
+#endif /* YAPOR_COW */
+  for (proc = 1; proc < Yap_number_workers; proc++) {
     int son;
     son = fork();
     if (son == -1)
@@ -286,7 +286,7 @@ void init_workers(void) {
       remap_memory();
       break;
     }
-    else worker_pid(proc) = son;
+    else Yap_worker_pid(proc) = son;
   }
 }
 #endif /* YAPOR */
diff --git a/OPTYap/opt.macros.h b/OPTYap/opt.macros.h
index e2f439fee..a9e95acdd 100644
--- a/OPTYap/opt.macros.h
+++ b/OPTYap/opt.macros.h
@@ -124,22 +124,22 @@ extern int Yap_page_size;
           if (shmctl(shmid, IPC_RMID, 0) != 0)                                                   \
             Yap_Error(FATAL_ERROR, TermNil, "shmctl error (ALLOC_PAGE)");                        \
           aux_pg_hd = (pg_hd_ptr)(((void *)PG_HD) + Yap_page_size);                              \
-          Pg_free_pg(GLOBAL_PAGES_void) = aux_pg_hd;                                             \
+          Pg_free_pg(Yap_pages_void) = aux_pg_hd;                                             \
           for (i = 2; i < SHMMAX / Yap_page_size; i++) {                                         \
             PgHd_next(aux_pg_hd) = (pg_hd_ptr)(((void *)aux_pg_hd) + Yap_page_size);             \
             aux_pg_hd = PgHd_next(aux_pg_hd);                                                    \
           }                                                                                      \
           PgHd_next(aux_pg_hd) = NULL;                                                           \
-          UPDATE_STATS(Pg_pg_alloc(GLOBAL_PAGES_void), SHMMAX / Yap_page_size);                  \
+          UPDATE_STATS(Pg_pg_alloc(Yap_pages_void), SHMMAX / Yap_page_size);                  \
         }
 
 #define RECOVER_UNUSED_SPACE(STR_PAGES)                                                          \
-        { sg_fr_ptr sg_fr = GLOBAL_check_sg_fr;                                                  \
+        { sg_fr_ptr sg_fr = Yap_check_sg_fr;                                                  \
           do {                                                                                   \
             if (sg_fr)                                                                           \
               sg_fr = SgFr_next(sg_fr);                                                          \
             else                                                                                 \
-              sg_fr = GLOBAL_first_sg_fr;                                                        \
+              sg_fr = Yap_first_sg_fr;                                                        \
             if (sg_fr == NULL)                                                                   \
               Yap_Error(FATAL_ERROR, TermNil, "no space left (RECOVER_UNUSED_SPACE)");           \
               /* see function 'InteractSIGINT' in file 'sysbits.c' */                            \
@@ -157,8 +157,8 @@ extern int Yap_page_size;
                                TRAVERSE_MODE_NORMAL, TRAVERSE_POSITION_FIRST);                   \
               TrNode_child(SgFr_answer_trie(sg_fr)) = NULL;                                      \
 	    }                                                                                    \
-          } while (Pg_free_pg(GLOBAL_PAGES_void) == Pg_free_pg(STR_PAGES));                      \
-          GLOBAL_check_sg_fr = sg_fr;                                                            \
+          } while (Pg_free_pg(Yap_pages_void) == Pg_free_pg(STR_PAGES));                      \
+          Yap_check_sg_fr = sg_fr;                                                            \
         }
 
 #define ALLOC_STRUCT(STR, STR_PAGES, STR_TYPE)                                                   \
@@ -167,20 +167,20 @@ extern int Yap_page_size;
           pg_hd = Pg_free_pg(STR_PAGES);                                                         \
           while (pg_hd == NULL) {                                                                \
             UNLOCK(Pg_lock(STR_PAGES));                                                          \
-            LOCK(Pg_lock(GLOBAL_PAGES_void));                                                    \
-            if (Pg_free_pg(GLOBAL_PAGES_void)) {                                                 \
-              pg_hd = Pg_free_pg(GLOBAL_PAGES_void);                                             \
-              Pg_free_pg(GLOBAL_PAGES_void) = PgHd_next(pg_hd);                                  \
-              UPDATE_STATS(Pg_str_in_use(GLOBAL_PAGES_void), 1);                                 \
-              UNLOCK(Pg_lock(GLOBAL_PAGES_void));                                                \
+            LOCK(Pg_lock(Yap_pages_void));                                                    \
+            if (Pg_free_pg(Yap_pages_void)) {                                                 \
+              pg_hd = Pg_free_pg(Yap_pages_void);                                             \
+              Pg_free_pg(Yap_pages_void) = PgHd_next(pg_hd);                                  \
+              UPDATE_STATS(Pg_str_in_use(Yap_pages_void), 1);                                 \
+              UNLOCK(Pg_lock(Yap_pages_void));                                                \
               INIT_PAGE(pg_hd, STR_PAGES, STR_TYPE);                                             \
-            } else if (GLOBAL_MAX_PAGES != Pg_pg_alloc(GLOBAL_PAGES_void)) {                     \
+            } else if (Yap_max_pages != Pg_pg_alloc(Yap_pages_void)) {                     \
               ALLOC_PAGE(pg_hd);                                                                 \
-              UPDATE_STATS(Pg_str_in_use(GLOBAL_PAGES_void), 1);                                 \
-              UNLOCK(Pg_lock(GLOBAL_PAGES_void));                                                \
+              UPDATE_STATS(Pg_str_in_use(Yap_pages_void), 1);                                 \
+              UNLOCK(Pg_lock(Yap_pages_void));                                                \
               INIT_PAGE(pg_hd, STR_PAGES, STR_TYPE);                                             \
             } else {                                                                             \
-              UNLOCK(Pg_lock(GLOBAL_PAGES_void));                                                \
+              UNLOCK(Pg_lock(Yap_pages_void));                                                \
               RECOVER_UNUSED_SPACE(STR_PAGES);                                                   \
               LOCK(Pg_lock(STR_PAGES));                                                          \
               pg_hd = Pg_free_pg(STR_PAGES);                                                     \
@@ -202,20 +202,20 @@ extern int Yap_page_size;
           pg_hd = Pg_free_pg(STR_PAGES);                                                         \
           while (pg_hd == NULL) {                                                                \
             UNLOCK(Pg_lock(STR_PAGES));                                                          \
-            LOCK(Pg_lock(GLOBAL_PAGES_void));                                                    \
-            if (Pg_free_pg(GLOBAL_PAGES_void)) {                                                 \
-              pg_hd = Pg_free_pg(GLOBAL_PAGES_void);                                             \
-              Pg_free_pg(GLOBAL_PAGES_void) = PgHd_next(pg_hd);                                  \
-              UPDATE_STATS(Pg_str_in_use(GLOBAL_PAGES_void), 1);                                 \
-              UNLOCK(Pg_lock(GLOBAL_PAGES_void));                                                \
+            LOCK(Pg_lock(Yap_pages_void));                                                    \
+            if (Pg_free_pg(Yap_pages_void)) {                                                 \
+              pg_hd = Pg_free_pg(Yap_pages_void);                                             \
+              Pg_free_pg(Yap_pages_void) = PgHd_next(pg_hd);                                  \
+              UPDATE_STATS(Pg_str_in_use(Yap_pages_void), 1);                                 \
+              UNLOCK(Pg_lock(Yap_pages_void));                                                \
               INIT_PAGE(pg_hd, STR_PAGES, STR_TYPE);                                             \
-            } else if (GLOBAL_MAX_PAGES != Pg_pg_alloc(GLOBAL_PAGES_void)) {                     \
+            } else if (Yap_max_pages != Pg_pg_alloc(Yap_pages_void)) {                     \
               ALLOC_PAGE(pg_hd);                                                                 \
-              UPDATE_STATS(Pg_str_in_use(GLOBAL_PAGES_void), 1);                                 \
-              UNLOCK(Pg_lock(GLOBAL_PAGES_void));                                                \
+              UPDATE_STATS(Pg_str_in_use(Yap_pages_void), 1);                                 \
+              UNLOCK(Pg_lock(Yap_pages_void));                                                \
               INIT_PAGE(pg_hd, STR_PAGES, STR_TYPE);                                             \
             } else {                                                                             \
-              UNLOCK(Pg_lock(GLOBAL_PAGES_void));                                                \
+              UNLOCK(Pg_lock(Yap_pages_void));                                                \
               RECOVER_UNUSED_SPACE(STR_PAGES);                                                   \
               LOCK(Pg_lock(STR_PAGES));                                                          \
               pg_hd = Pg_free_pg(STR_PAGES);                                                     \
@@ -235,8 +235,8 @@ extern int Yap_page_size;
 **                          SHM_MEMORY_ALLOC_SCHEME && !LIMIT_TABLING                           **
 *************************************************************************************************/
 #define ALLOC_PAGE(PG_HD)                                                                        \
-        LOCK(Pg_lock(GLOBAL_PAGES_void));                                                        \
-        if (Pg_free_pg(GLOBAL_PAGES_void) == NULL) {                                             \
+        LOCK(Pg_lock(Yap_pages_void));                                                        \
+        if (Pg_free_pg(Yap_pages_void) == NULL) {                                             \
           int i, shmid;                                                                          \
           pg_hd_ptr pg_hd, aux_pg_hd;                                                            \
           if ((shmid = shmget(IPC_PRIVATE, SHMMAX, SHM_R|SHM_W)) == -1)                          \
@@ -245,19 +245,19 @@ extern int Yap_page_size;
             Yap_Error(FATAL_ERROR, TermNil, "shmat error (ALLOC_PAGE)");                         \
           if (shmctl(shmid, IPC_RMID, 0) != 0)                                                   \
             Yap_Error(FATAL_ERROR, TermNil, "shmctl error (ALLOC_PAGE)");                        \
-          Pg_free_pg(GLOBAL_PAGES_void) = pg_hd;                                                 \
+          Pg_free_pg(Yap_pages_void) = pg_hd;                                                 \
           for (i = 1; i < SHMMAX / Yap_page_size; i++) {                                         \
             aux_pg_hd = (pg_hd_ptr)(((void *)pg_hd) + Yap_page_size);                            \
             PgHd_next(pg_hd) = aux_pg_hd;                                                        \
             pg_hd = aux_pg_hd;                                                                   \
           }                                                                                      \
           PgHd_next(pg_hd) = NULL;                                                               \
-          UPDATE_STATS(Pg_pg_alloc(GLOBAL_PAGES_void), SHMMAX / Yap_page_size);                  \
+          UPDATE_STATS(Pg_pg_alloc(Yap_pages_void), SHMMAX / Yap_page_size);                  \
         }                                                                                        \
-        UPDATE_STATS(Pg_str_in_use(GLOBAL_PAGES_void), 1);                                       \
-        PG_HD = Pg_free_pg(GLOBAL_PAGES_void);                                                   \
-        Pg_free_pg(GLOBAL_PAGES_void) = PgHd_next(PG_HD);                                        \
-        UNLOCK(Pg_lock(GLOBAL_PAGES_void))
+        UPDATE_STATS(Pg_str_in_use(Yap_pages_void), 1);                                       \
+        PG_HD = Pg_free_pg(Yap_pages_void);                                                   \
+        Pg_free_pg(Yap_pages_void) = PgHd_next(PG_HD);                                        \
+        UNLOCK(Pg_lock(Yap_pages_void))
 
 #define ALLOC_STRUCT(STR, STR_PAGES, STR_TYPE)                                                   \
         { pg_hd_ptr pg_hd;                                                                       \
@@ -331,11 +331,11 @@ extern int Yap_page_size;
 **                                   SHM_MEMORY_ALLOC_SCHEME                                    **
 *************************************************************************************************/
 #define FREE_PAGE(PG_HD)                                                                         \
-        LOCK(Pg_lock(GLOBAL_PAGES_void));                                                        \
-        UPDATE_STATS(Pg_str_in_use(GLOBAL_PAGES_void), -1);                                      \
-        PgHd_next(PG_HD) = Pg_free_pg(GLOBAL_PAGES_void);                                        \
-        Pg_free_pg(GLOBAL_PAGES_void) = PG_HD;                                                   \
-        UNLOCK(Pg_lock(GLOBAL_PAGES_void))
+        LOCK(Pg_lock(Yap_pages_void));                                                        \
+        UPDATE_STATS(Pg_str_in_use(Yap_pages_void), -1);                                      \
+        PgHd_next(PG_HD) = Pg_free_pg(Yap_pages_void);                                        \
+        Pg_free_pg(Yap_pages_void) = PG_HD;                                                   \
+        UNLOCK(Pg_lock(Yap_pages_void))
 
 #define FREE_STRUCT(STR, STR_PAGES, STR_TYPE)                                                    \
         { pg_hd_ptr pg_hd;                                                                       \
@@ -375,55 +375,55 @@ extern int Yap_page_size;
         }
 #define FREE_HASH_BUCKETS(BUCKET_PTR)  FREE_BLOCK(BUCKET_PTR)
 
-#define ALLOC_OR_FRAME(STR)            ALLOC_STRUCT(STR, GLOBAL_PAGES_or_fr, struct or_frame)
-#define FREE_OR_FRAME(STR)             FREE_STRUCT(STR, GLOBAL_PAGES_or_fr, struct or_frame)
+#define ALLOC_OR_FRAME(STR)            ALLOC_STRUCT(STR, Yap_pages_or_fr , struct or_frame)
+#define FREE_OR_FRAME(STR)             FREE_STRUCT(STR, Yap_pages_or_fr , struct or_frame)
 
-#define ALLOC_QG_SOLUTION_FRAME(STR)   ALLOC_STRUCT(STR, GLOBAL_PAGES_qg_sol_fr, struct query_goal_solution_frame)
-#define FREE_QG_SOLUTION_FRAME(STR)    FREE_STRUCT(STR, GLOBAL_PAGES_qg_sol_fr, struct query_goal_solution_frame)
+#define ALLOC_QG_SOLUTION_FRAME(STR)   ALLOC_STRUCT(STR, Yap_pages_qg_sol_fr , struct query_goal_solution_frame)
+#define FREE_QG_SOLUTION_FRAME(STR)    FREE_STRUCT(STR, Yap_pages_qg_sol_fr , struct query_goal_solution_frame)
 
-#define ALLOC_QG_ANSWER_FRAME(STR)     ALLOC_STRUCT(STR, GLOBAL_PAGES_qg_ans_fr, struct query_goal_answer_frame)
-#define FREE_QG_ANSWER_FRAME(STR)      FREE_STRUCT(STR, GLOBAL_PAGES_qg_ans_fr, struct query_goal_answer_frame)
+#define ALLOC_QG_ANSWER_FRAME(STR)     ALLOC_STRUCT(STR, Yap_pages_qg_ans_fr, struct query_goal_answer_frame)
+#define FREE_QG_ANSWER_FRAME(STR)      FREE_STRUCT(STR, Yap_pages_qg_ans_fr, struct query_goal_answer_frame)
 
-#define ALLOC_TG_SOLUTION_FRAME(STR)   ALLOC_STRUCT(STR, GLOBAL_PAGES_tg_sol_fr, struct table_subgoal_solution_frame)
-#define FREE_TG_SOLUTION_FRAME(STR)    FREE_STRUCT(STR, GLOBAL_PAGES_tg_sol_fr, struct table_subgoal_solution_frame)
+#define ALLOC_TG_SOLUTION_FRAME(STR)   ALLOC_STRUCT(STR, Yap_pages_tg_sol_fr, struct table_subgoal_solution_frame)
+#define FREE_TG_SOLUTION_FRAME(STR)    FREE_STRUCT(STR, Yap_pages_tg_sol_fr, struct table_subgoal_solution_frame)
 
-#define ALLOC_TG_ANSWER_FRAME(STR)     ALLOC_STRUCT(STR, GLOBAL_PAGES_tg_ans_fr, struct table_subgoal_answer_frame)
-#define FREE_TG_ANSWER_FRAME(STR)      FREE_STRUCT(STR, GLOBAL_PAGES_tg_ans_fr, struct table_subgoal_answer_frame)
+#define ALLOC_TG_ANSWER_FRAME(STR)     ALLOC_STRUCT(STR, Yap_pages_tg_ans_fr, struct table_subgoal_answer_frame)
+#define FREE_TG_ANSWER_FRAME(STR)      FREE_STRUCT(STR, Yap_pages_tg_ans_fr, struct table_subgoal_answer_frame)
 
-#define ALLOC_TABLE_ENTRY(STR)         ALLOC_STRUCT(STR, GLOBAL_PAGES_tab_ent, struct table_entry)
-#define FREE_TABLE_ENTRY(STR)          FREE_STRUCT(STR, GLOBAL_PAGES_tab_ent, struct table_entry)
+#define ALLOC_TABLE_ENTRY(STR)         ALLOC_STRUCT(STR, Yap_pages_tab_ent, struct table_entry)
+#define FREE_TABLE_ENTRY(STR)          FREE_STRUCT(STR, Yap_pages_tab_ent, struct table_entry)
 
-#define ALLOC_SUBGOAL_FRAME(STR)       ALLOC_STRUCT(STR, GLOBAL_PAGES_sg_fr, struct subgoal_frame)
-#define FREE_SUBGOAL_FRAME(STR)        FREE_STRUCT(STR, GLOBAL_PAGES_sg_fr, struct subgoal_frame)
+#define ALLOC_SUBGOAL_FRAME(STR)       ALLOC_STRUCT(STR, Yap_pages_sg_fr, struct subgoal_frame)
+#define FREE_SUBGOAL_FRAME(STR)        FREE_STRUCT(STR, Yap_pages_sg_fr, struct subgoal_frame)
 
-#define ALLOC_DEPENDENCY_FRAME(STR)    ALLOC_STRUCT(STR, GLOBAL_PAGES_dep_fr, struct dependency_frame)
-#define FREE_DEPENDENCY_FRAME(STR)     FREE_STRUCT(STR, GLOBAL_PAGES_dep_fr, struct dependency_frame)
+#define ALLOC_DEPENDENCY_FRAME(STR)    ALLOC_STRUCT(STR, Yap_pages_dep_fr, struct dependency_frame)
+#define FREE_DEPENDENCY_FRAME(STR)     FREE_STRUCT(STR, Yap_pages_dep_fr, struct dependency_frame)
 
-#define ALLOC_SUSPENSION_FRAME(STR)    ALLOC_STRUCT(STR, GLOBAL_PAGES_susp_fr, struct suspension_frame)
+#define ALLOC_SUSPENSION_FRAME(STR)    ALLOC_STRUCT(STR, Yap_pages_susp_fr, struct suspension_frame)
 #define FREE_SUSPENSION_FRAME(STR)     FREE_BLOCK(SuspFr_global_start(STR));                         \
-                                       FREE_STRUCT(STR, GLOBAL_PAGES_susp_fr, struct suspension_frame)
+                                       FREE_STRUCT(STR, Yap_pages_susp_fr, struct suspension_frame)
 
-#define ALLOC_GLOBAL_TRIE_NODE(STR)    ALLOC_STRUCT(STR, GLOBAL_PAGES_gt_node, struct global_trie_node)
-#define FREE_GLOBAL_TRIE_NODE(STR)     FREE_STRUCT(STR, GLOBAL_PAGES_gt_node, struct global_trie_node)
+#define ALLOC_GLOBAL_TRIE_NODE(STR)    ALLOC_STRUCT(STR, Yap_pages_gt_node, struct global_trie_node)
+#define FREE_GLOBAL_TRIE_NODE(STR)     FREE_STRUCT(STR, Yap_pages_gt_node, struct global_trie_node)
 
-#define ALLOC_SUBGOAL_TRIE_NODE(STR)   ALLOC_STRUCT(STR, GLOBAL_PAGES_sg_node, struct subgoal_trie_node)
-#define FREE_SUBGOAL_TRIE_NODE(STR)    FREE_STRUCT(STR, GLOBAL_PAGES_sg_node, struct subgoal_trie_node)
+#define ALLOC_SUBGOAL_TRIE_NODE(STR)   ALLOC_STRUCT(STR, Yap_pages_sg_node, struct subgoal_trie_node)
+#define FREE_SUBGOAL_TRIE_NODE(STR)    FREE_STRUCT(STR, Yap_pages_sg_node, struct subgoal_trie_node)
 
 #ifdef YAPOR
-#define ALLOC_ANSWER_TRIE_NODE(STR)    ALLOC_NEXT_FREE_STRUCT(STR, GLOBAL_PAGES_ans_node, struct answer_trie_node)
+#define ALLOC_ANSWER_TRIE_NODE(STR)    ALLOC_NEXT_FREE_STRUCT(STR, Yap_pages_ans_node, struct answer_trie_node)
 #else /* TABLING */
-#define ALLOC_ANSWER_TRIE_NODE(STR)    ALLOC_STRUCT(STR, GLOBAL_PAGES_ans_node, struct answer_trie_node)
+#define ALLOC_ANSWER_TRIE_NODE(STR)    ALLOC_STRUCT(STR, Yap_pages_ans_node, struct answer_trie_node)
 #endif /* YAPOR - TABLING */
-#define FREE_ANSWER_TRIE_NODE(STR)     FREE_STRUCT(STR, GLOBAL_PAGES_ans_node, struct answer_trie_node)
+#define FREE_ANSWER_TRIE_NODE(STR)     FREE_STRUCT(STR, Yap_pages_ans_node, struct answer_trie_node)
 
-#define ALLOC_GLOBAL_TRIE_HASH(STR)    ALLOC_STRUCT(STR, GLOBAL_PAGES_gt_hash, struct global_trie_hash)
-#define FREE_GLOBAL_TRIE_HASH(STR)     FREE_STRUCT(STR, GLOBAL_PAGES_gt_hash, struct global_trie_hash)
+#define ALLOC_GLOBAL_TRIE_HASH(STR)    ALLOC_STRUCT(STR, Yap_pages_gt_hash, struct global_trie_hash)
+#define FREE_GLOBAL_TRIE_HASH(STR)     FREE_STRUCT(STR, Yap_pages_gt_hash, struct global_trie_hash)
 
-#define ALLOC_SUBGOAL_TRIE_HASH(STR)   ALLOC_STRUCT(STR, GLOBAL_PAGES_sg_hash, struct subgoal_trie_hash)
-#define FREE_SUBGOAL_TRIE_HASH(STR)    FREE_STRUCT(STR, GLOBAL_PAGES_sg_hash, struct subgoal_trie_hash)
+#define ALLOC_SUBGOAL_TRIE_HASH(STR)   ALLOC_STRUCT(STR, Yap_pages_sg_hash, struct subgoal_trie_hash)
+#define FREE_SUBGOAL_TRIE_HASH(STR)    FREE_STRUCT(STR, Yap_pages_sg_hash, struct subgoal_trie_hash)
 
-#define ALLOC_ANSWER_TRIE_HASH(STR)    ALLOC_STRUCT(STR, GLOBAL_PAGES_ans_hash, struct answer_trie_hash)
-#define FREE_ANSWER_TRIE_HASH(STR)     FREE_STRUCT(STR, GLOBAL_PAGES_ans_hash, struct answer_trie_hash)
+#define ALLOC_ANSWER_TRIE_HASH(STR)    ALLOC_STRUCT(STR, Yap_pages_ans_hash, struct answer_trie_hash)
+#define FREE_ANSWER_TRIE_HASH(STR)     FREE_STRUCT(STR, Yap_pages_ans_hash, struct answer_trie_hash)
 
 
 
diff --git a/OPTYap/opt.mavar.h b/OPTYap/opt.mavar.h
index 0613590f7..c198f06cf 100644
--- a/OPTYap/opt.mavar.h
+++ b/OPTYap/opt.mavar.h
@@ -35,7 +35,7 @@ typedef struct {
 
 extern ma_hash_entry Yap_ma_hash_table[MAVARS_HASH_SIZE];
 
-extern UInt Yap_timestamp;    /* an unsigned int */
+extern UInt Yap_ma_timestamp;    /* an unsigned int */
 
 OPT_MAVAR_STATIC unsigned int Yap_MAVAR_HASH(CELL *);
 OPT_MAVAR_STATIC struct ma_h_entry *Yap_ALLOC_NEW_MASPACE(void);
@@ -66,8 +66,8 @@ Yap_lookup_ma_var(CELL *addr) {
   unsigned int i = Yap_MAVAR_HASH(addr);
   struct ma_h_entry *nptr, *optr;
 
-  if (Yap_ma_hash_table[i].timestmp != Yap_timestamp) {
-    Yap_ma_hash_table[i].timestmp = Yap_timestamp;
+  if (Yap_ma_hash_table[i].timestmp != Yap_ma_timestamp) {
+    Yap_ma_hash_table[i].timestmp = Yap_ma_timestamp;
     Yap_ma_hash_table[i].val.addr = addr;
     Yap_ma_hash_table[i].val.next = NULL;
     return FALSE;
@@ -91,13 +91,13 @@ Yap_lookup_ma_var(CELL *addr) {
 
 OPT_MAVAR_STATIC UInt
 Yap_NEW_MAHASH(ma_h_inner_struct *top) {
-  UInt time = ++Yap_timestamp;
+  UInt time = ++Yap_ma_timestamp;
   if (time == 0) {
     unsigned int i;
     /* damn, we overflowed */
     for (i = 0; i < MAVARS_HASH_SIZE; i++)
       Yap_ma_hash_table[i].timestmp = 0;
-    time = ++Yap_timestamp;
+    time = ++Yap_ma_timestamp;
   }
   Yap_ma_h_top = top;
   return time;
diff --git a/OPTYap/opt.memory.c b/OPTYap/opt.memory.c
index bac5ca4cd..d7dadb103 100644
--- a/OPTYap/opt.memory.c
+++ b/OPTYap/opt.memory.c
@@ -82,12 +82,12 @@ close_mapfile(void) {
 
 void map_memory(long HeapArea, long GlobalLocalArea, long TrailAuxArea, int n_workers) {
   void *mmap_addr = (void *)MMAP_ADDR;
-#ifdef ACOW
+#ifdef YAPOR_COW
   int private_fd_mapfile;
 #if MMAP_MEMORY_MAPPING_SCHEME
   long TotalArea;
 #endif /* MMAP_MEMORY_MAPPING_SCHEME */
-#else /* ENV_COPY || SBA */
+#else /* YAPOR_COPY || YAPOR_SBA */
   int i;
   long WorkerArea;
   long TotalArea;
@@ -100,21 +100,21 @@ void map_memory(long HeapArea, long GlobalLocalArea, long TrailAuxArea, int n_wo
 
   /* we'll need this later */
 #if defined(YAPOR) && !defined(THREADS)
-  Yap_global = (struct worker_shared *)( mmap_addr  - sizeof(struct worker_shared));
-  Yap_WLocal =  (struct worker_local *)( mmap_addr  - (sizeof(struct worker_shared)+MAX_WORKERS*sizeof(struct worker_local)));
-  extra_area = ADJUST_SIZE_TO_PAGE(sizeof(struct worker_shared)+MAX_WORKERS*sizeof(struct worker_local));
+  Yap_global = (struct global_data *)( mmap_addr  - sizeof(struct global_data));
+  Yap_WLocal =  (struct worker_local *)( mmap_addr  - (sizeof(struct global_data)+MAX_WORKERS*sizeof(struct worker_local)));
+  extra_area = ADJUST_SIZE_TO_PAGE(sizeof(struct global_data)+MAX_WORKERS*sizeof(struct worker_local));
 #endif
   Yap_HeapBase = (ADDR)mmap_addr;
   Yap_GlobalBase = mmap_addr + HeapArea;
 
   /* shared memory allocation - model dependent */
-#ifdef ACOW
+#ifdef YAPOR_COW
   /* acow just needs one stack */
 #ifdef MMAP_MEMORY_MAPPING_SCHEME
   /* I need this for MMAP to know what it must allocate */
   TotalArea = HeapArea;
 #endif /* MMAP_MEMORY_MAPPING_SCHEME */
-#else /* ENV_COPY || SBA */
+#else /* YAPOR_COPY || YAPOR_SBA */
   /* the others need n stacks */
   WorkerArea = ADJUST_SIZE_TO_PAGE(GlobalLocalArea + TrailAuxArea);
   TotalArea = HeapArea + WorkerArea * n_workers;
@@ -131,16 +131,16 @@ void map_memory(long HeapArea, long GlobalLocalArea, long TrailAuxArea, int n_wo
 #endif
 #else /* SHM_MEMORY_MAPPING_SCHEME */
 /* Most systems are limited regarding what we can allocate */
-#ifdef ACOW
+#ifdef YAPOR_COW
   /* single shared segment in ACOW */
   shm_map_memory(0, HeapArea, mmap_addr);
-#else /* ENV_COPY || SBA */
+#else /* YAPOR_COPY || YAPOR_SBA */
   /* place as segment n otherwise (0..n-1 reserved for worker areas */
   shm_map_memory(n_workers, HeapArea, mmap_addr);
 #endif /* YAPOR_MODEL */
 #endif /* MEMORY_MAPPING_SCHEME */
 
-#ifdef ACOW
+#ifdef YAPOR_COW
   /* just allocate local space for stacks */
   if ((private_fd_mapfile = open("/dev/zero", O_RDWR)) < 0)
     Yap_Error(FATAL_ERROR, TermNil, "open error (map_memory)");
@@ -148,7 +148,7 @@ void map_memory(long HeapArea, long GlobalLocalArea, long TrailAuxArea, int n_wo
            MAP_PRIVATE|MAP_FIXED, private_fd_mapfile, 0) == (void *) -1)
     Yap_Error(FATAL_ERROR, TermNil, "mmap error (map_memory)");
   close(private_fd_mapfile);
-#else /* ENV_COPY || SBA */
+#else /* YAPOR_COPY || YAPOR_SBA */
   for (i = 0; i < n_workers; i++) {
     /* initialize worker vars */
     worker_area(i) = Yap_GlobalBase + i * WorkerArea;
@@ -160,7 +160,7 @@ void map_memory(long HeapArea, long GlobalLocalArea, long TrailAuxArea, int n_wo
   }
 #endif /* YAPOR_MODEL */
 
-#ifdef SBA
+#ifdef YAPOR_SBA
   /* alloc space for the sparse binding array */
   sba_size = WorkerArea * n_workers;
   if ((binding_array = (char *)malloc(sba_size)) == NULL)
@@ -170,7 +170,7 @@ void map_memory(long HeapArea, long GlobalLocalArea, long TrailAuxArea, int n_wo
   }
   sba_offset = binding_array - Yap_GlobalBase;
   sba_end = (int)binding_array + sba_size;
-#endif /* SBA */
+#endif /* YAPOR_SBA */
   Yap_TrailBase = Yap_GlobalBase + GlobalLocalArea;
   Yap_LocalBase = Yap_TrailBase - CellSize;
 
@@ -193,30 +193,30 @@ void unmap_memory (void) {
   {
     int proc;
     INFORMATION_MESSAGE("Worker %d exiting...", worker_id);
-    for (proc = 0; proc < number_workers; proc++) {
-      if (proc != worker_id && worker_pid(proc) != 0) {
-        if (kill(worker_pid(proc), SIGKILL) != 0)
-          INFORMATION_MESSAGE("Can't kill process %d", worker_pid(proc));
+    for (proc = 0; proc < Yap_number_workers; proc++) {
+      if (proc != worker_id && Yap_worker_pid(proc) != 0) {
+        if (kill(Yap_worker_pid(proc), SIGKILL) != 0)
+          INFORMATION_MESSAGE("Can't kill process %d", Yap_worker_pid(proc));
         else 
-          INFORMATION_MESSAGE("Killing process %d", worker_pid(proc));
+          INFORMATION_MESSAGE("Killing process %d", Yap_worker_pid(proc));
       }
     }
-#ifdef ACOW
-    if (number_workers > 1) {
-      if (kill(GLOBAL_master_worker, SIGINT) != 0)
-	INFORMATION_MESSAGE("Can't kill process %d", GLOBAL_master_worker);
+#ifdef YAPOR_COW
+    if (Yap_number_workers > 1) {
+      if (kill(Yap_master_worker, SIGINT) != 0)
+	INFORMATION_MESSAGE("Can't kill process %d", Yap_master_worker);
       else 
-	INFORMATION_MESSAGE("Killing process %d", GLOBAL_master_worker);
+	INFORMATION_MESSAGE("Killing process %d", Yap_master_worker);
     }
-#endif /* ACOW */
+#endif /* YAPOR_COW */
   }
 
 #ifdef SHM_MEMORY_MAPPING_SCHEME
-#ifdef ACOW
+#ifdef YAPOR_COW
   i = 0;
 #else
-  for (i = 0; i < number_workers + 1; i++)
-#endif /* ACOW */
+  for (i = 0; i < Yap_number_workers + 1; i++)
+#endif /* YAPOR_COW */
   {
     if (shmctl(shm_mapid[i], IPC_RMID, 0) == 0)
       INFORMATION_MESSAGE("Removing shared memory segment %d", shm_mapid[i]);
@@ -224,10 +224,10 @@ void unmap_memory (void) {
   }
 #else /* MMAP_MEMORY_MAPPING_SCHEME */
   strcpy(MapFile,"./mapfile");
-#ifdef ACOW
-  itos(GLOBAL_master_worker, &MapFile[9]);
-#else /* ENV_COPY || SBA */
-  itos(worker_pid(0), &MapFile[9]);
+#ifdef YAPOR_COW
+  itos(Yap_master_worker, &MapFile[9]);
+#else /* YAPOR_COPY || YAPOR_SBA */
+  itos(Yap_worker_pid(0), &MapFile[9]);
 #endif
   if (remove(MapFile) == 0)
     INFORMATION_MESSAGE("Removing mapfile \"%s\"", MapFile);
@@ -238,10 +238,10 @@ void unmap_memory (void) {
 
 
 void remap_memory(void) {
-#ifdef ACOW
+#ifdef YAPOR_COW
   /* do nothing */
-#endif /* ACOW */
-#ifdef SBA
+#endif /* YAPOR_COW */
+#ifdef YAPOR_SBA
   /* setup workers so that they have different areas */
   long WorkerArea = worker_offset(1);
 
@@ -249,8 +249,8 @@ void remap_memory(void) {
   Yap_TrailBase += worker_id * WorkerArea;
   Yap_LocalBase += worker_id * WorkerArea;
   Yap_TrailTop += worker_id * WorkerArea;
-#endif /* SBA */
-#ifdef ENV_COPY
+#endif /* YAPOR_SBA */
+#ifdef YAPOR_COPY
   void *remap_addr;
   long remap_offset;
   long WorkerArea;
@@ -260,28 +260,28 @@ void remap_memory(void) {
   remap_offset = (char *)remap_addr - (char *)Yap_HeapBase;
   WorkerArea = worker_offset(1);
 #ifdef SHM_MEMORY_MAPPING_SCHEME
-  for (i = 0; i < number_workers; i++) {
+  for (i = 0; i < Yap_number_workers; i++) {
     if (shmdt(worker_area(i)) == -1)
       Yap_Error(FATAL_ERROR, TermNil, "shmdt error (remap_memory)");
   }
-  for (i = 0; i < number_workers; i++) {
-    worker_area(i) = remap_addr + ((number_workers + i - worker_id) % number_workers) * WorkerArea;
+  for (i = 0; i < Yap_number_workers; i++) {
+    worker_area(i) = remap_addr + ((Yap_number_workers + i - worker_id) % Yap_number_workers) * WorkerArea;
     if(shmat(shm_mapid[i], worker_area(i), 0) == (void *) -1)
       Yap_Error(FATAL_ERROR, TermNil, "shmat error (remap_memory)");
   }
 #else /* MMAP_MEMORY_MAPPING_SCHEME */
-  if (munmap(remap_addr, (size_t)(WorkerArea * number_workers)) == -1)
+  if (munmap(remap_addr, (size_t)(WorkerArea * Yap_number_workers)) == -1)
     Yap_Error(FATAL_ERROR, TermNil, "munmap error (remap_memory)");
-  for (i = 0; i < number_workers; i++) {
-    worker_area(i) = remap_addr + ((number_workers + i - worker_id) % number_workers) * WorkerArea;
+  for (i = 0; i < Yap_number_workers; i++) {
+    worker_area(i) = remap_addr + ((Yap_number_workers + i - worker_id) % Yap_number_workers) * WorkerArea;
     if (mmap(worker_area(i), (size_t)WorkerArea, PROT_READ|PROT_WRITE, 
         MAP_SHARED|MAP_FIXED, fd_mapfile, remap_offset + i * WorkerArea + extra_area) == (void *) -1)
       Yap_Error(FATAL_ERROR, TermNil, "mmap error (remap_memory)");
   }
 #endif /* MEMORY_MAPPING_SCHEME */
-  for (i = 0; i < number_workers; i++) {
+  for (i = 0; i < Yap_number_workers; i++) {
     worker_offset(i) = worker_area(i) - worker_area(worker_id);
   }
-#endif /* ENV_COPY */
+#endif /* YAPOR_COPY */
 }
 #endif /* YAPOR && !THREADS */
diff --git a/OPTYap/opt.preds.c b/OPTYap/opt.preds.c
index 7f1745077..f16652fcb 100644
--- a/OPTYap/opt.preds.c
+++ b/OPTYap/opt.preds.c
@@ -159,7 +159,7 @@ void Yap_init_optyap_preds(void) {
 
 #ifdef YAPOR
 void finish_yapor(void) {
-  GLOBAL_execution_time = current_time() - GLOBAL_execution_time;
+  Yap_execution_time = current_time() - Yap_execution_time;
   show_answers();
   return;
 }
@@ -360,7 +360,7 @@ static Int p_abolish_all_tables( USES_REGS1 ) {
   sg_hash_ptr hash;
   sg_node_ptr sg_node;
 
-  tab_ent = GLOBAL_root_tab_ent;
+  tab_ent = Yap_root_tab_ent;
   while(tab_ent) {
     hash = TabEnt_hash_chain(tab_ent);
     TabEnt_hash_chain(tab_ent) = NULL;
@@ -388,7 +388,7 @@ static Int p_abolish_all_tables( USES_REGS1 ) {
 static Int p_show_tabled_predicates( USES_REGS1 ) {
   tab_ent_ptr tab_ent;
 
-  tab_ent = GLOBAL_root_tab_ent;
+  tab_ent = Yap_root_tab_ent;
   fprintf(Yap_stdout, "Tabled predicates\n");
   if (tab_ent == NULL)
     fprintf(Yap_stdout, "  NONE\n");
@@ -421,7 +421,7 @@ static Int p_show_table( USES_REGS1 ) {
 static Int p_show_all_tables( USES_REGS1 ) {
   tab_ent_ptr tab_ent;
 
-  tab_ent = GLOBAL_root_tab_ent;
+  tab_ent = Yap_root_tab_ent;
   while(tab_ent) {
     show_table(tab_ent, SHOW_MODE_STRUCTURE);
     tab_ent = TabEnt_next(tab_ent);
@@ -479,9 +479,9 @@ static Int p_show_statistics_tabling( USES_REGS1 ) {
   total_bytes += aux_bytes;
 #ifdef SHM_MEMORY_ALLOC_SCHEME
   fprintf(Yap_stdout, "Total memory in use (I+II+III):    %10ld bytes (%ld pages in use)\n",
-          total_bytes, Pg_str_in_use(GLOBAL_PAGES_void));
+          total_bytes, Pg_str_in_use(Yap_pages_void));
   fprintf(Yap_stdout, "Total memory allocated:            %10ld bytes (%ld pages in total)\n",
-          Pg_pg_alloc(GLOBAL_PAGES_void) * Yap_page_size, Pg_pg_alloc(GLOBAL_PAGES_void));
+          Pg_pg_alloc(Yap_pages_void) * Yap_page_size, Pg_pg_alloc(Yap_pages_void));
 #else 
   fprintf(Yap_stdout, "Total memory in use (I+II+III):    %10ld bytes\n", total_bytes);
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
@@ -502,7 +502,7 @@ static Int p_show_statistics_global_trie( USES_REGS1 ) {
 
 static Int p_yapor_threads( USES_REGS1 ) {
 #if defined(YAPOR) && defined(THREADS)
-  return Yap_unify(MkIntegerTerm(number_workers),ARG1);
+  return Yap_unify(MkIntegerTerm(Yap_number_workers),ARG1);
 #else
   return FALSE;
 #endif
@@ -518,25 +518,25 @@ static Int p_worker( USES_REGS1 ) {
 
 
 static Int p_yapor_on( USES_REGS1 ) {
-  return (PARALLEL_EXECUTION_MODE);
+  return (Yap_parallel_execution_mode);
 }
 
 
 static Int p_start_yapor( USES_REGS1 ) {
 #ifdef TIMESTAMP_CHECK
-  GLOBAL_timestamp = 0;
+  Yap_timestamp = 0;
 #endif /* TIMESTAMP_CHECK */
-  GLOBAL_answers = NO_ANSWER;
-  BITMAP_delete(GLOBAL_bm_idle_workers, 0);
-  BITMAP_clear(GLOBAL_bm_invisible_workers);
-  BITMAP_clear(GLOBAL_bm_requestable_workers);
+  Yap_answers = NO_ANSWER;
+  BITMAP_delete(Yap_bm_idle_workers, 0);
+  BITMAP_clear(Yap_bm_invisible_workers);
+  BITMAP_clear(Yap_bm_requestable_workers);
 #ifdef TABLING_INNER_CUTS
-  BITMAP_clear(GLOBAL_bm_pruning_workers);
+  BITMAP_clear(Yap_bm_pruning_workers);
 #endif /* TABLING_INNER_CUTS */
   make_root_choice_point();
-  GLOBAL_performance_mode &= ~PERFORMANCE_IN_EXECUTION;
-  GLOBAL_execution_time = current_time();
-  BITMAP_clear(GLOBAL_bm_finished_workers);
+  Yap_performance_mode &= ~PERFORMANCE_IN_EXECUTION;
+  Yap_execution_time = current_time();
+  BITMAP_clear(Yap_bm_finished_workers);
   PUT_IN_EXECUTING(worker_id);
   return (TRUE);
 }
@@ -575,7 +575,7 @@ static Int p_execution_mode( USES_REGS1 ) {
   t = Deref(ARG1);
   if (IsVarTerm(t)) {
     Term ta;
-    if (PARALLEL_EXECUTION_MODE) 
+    if (Yap_parallel_execution_mode) 
       ta = MkAtomTerm(Yap_LookupAtom("parallel"));
     else 
       ta = MkAtomTerm(Yap_LookupAtom("sequential"));
@@ -586,11 +586,11 @@ static Int p_execution_mode( USES_REGS1 ) {
     char *s;
     s = RepAtom(AtomOfTerm(t))->StrOfAE;
     if (strcmp(s,"parallel") == 0) {
-      PARALLEL_EXECUTION_MODE = TRUE;
+      Yap_parallel_execution_mode = TRUE;
       return(TRUE);
     } 
     if (strcmp(s,"sequential") == 0) {
-      PARALLEL_EXECUTION_MODE = FALSE;
+      Yap_parallel_execution_mode = FALSE;
       return(TRUE);
     }
   }
@@ -603,11 +603,11 @@ static Int p_performance( USES_REGS1 ) {
   realtime one_worker_execution_time = 0;
   int i;
 
-  GLOBAL_performance_mode |= PERFORMANCE_IN_EXECUTION;
+  Yap_performance_mode |= PERFORMANCE_IN_EXECUTION;
   t = Deref(ARG1);
   if (IsVarTerm(t)) {
     Term ta;
-    if (GLOBAL_performance_mode & PERFORMANCE_ON) {
+    if (Yap_performance_mode & PERFORMANCE_ON) {
       ta = MkAtomTerm(Yap_LookupAtom("on"));
     } else { 
       ta = MkAtomTerm(Yap_LookupAtom("off"));
@@ -619,16 +619,16 @@ static Int p_performance( USES_REGS1 ) {
     char *s;
     s = RepAtom(AtomOfTerm(t))->StrOfAE;
     if (strcmp(s, "on") == 0) {
-      GLOBAL_performance_mode |= PERFORMANCE_ON;
+      Yap_performance_mode |= PERFORMANCE_ON;
       return(TRUE);
     } 
     if (strcmp(s,"off") == 0) {
-      GLOBAL_performance_mode &= ~PERFORMANCE_ON;
+      Yap_performance_mode &= ~PERFORMANCE_ON;
       return(TRUE);
     }
     if (strcmp(s,"clear") == 0) {
-      GLOBAL_number_goals = 0;
-      GLOBAL_best_times(0) = 0;
+      Yap_number_goals = 0;
+      Yap_best_times(0) = 0;
       return(TRUE);
     }
   }
@@ -639,31 +639,31 @@ static Int p_performance( USES_REGS1 ) {
   else 
     return(FALSE);
 
-  if (GLOBAL_number_goals) {
+  if (Yap_number_goals) {
     fprintf(Yap_stdout, "[\n  Best execution times:\n");
-    for (i = 1; i <= GLOBAL_number_goals; i++) {
-      fprintf(Yap_stdout, "    %d. time: %f seconds", i, GLOBAL_best_times(i));  
+    for (i = 1; i <= Yap_number_goals; i++) {
+      fprintf(Yap_stdout, "    %d. time: %f seconds", i, Yap_best_times(i));  
       if (one_worker_execution_time != 0)
         fprintf(Yap_stdout, " --> speedup %f (%6.2f %% )\n",
-                one_worker_execution_time / GLOBAL_best_times(i),
-                one_worker_execution_time / GLOBAL_best_times(i) / number_workers * 100 );
+                one_worker_execution_time / Yap_best_times(i),
+                one_worker_execution_time / Yap_best_times(i) / Yap_number_workers* 100 );
       else fprintf(Yap_stdout, "\n");
     }
 
     fprintf(Yap_stdout, "  Average             : %f seconds",
-            GLOBAL_best_times(0) / GLOBAL_number_goals);
+            Yap_best_times(0) / Yap_number_goals);
     if (one_worker_execution_time != 0)
       fprintf(Yap_stdout, " --> speedup %f (%6.2f %% )",
-              one_worker_execution_time * GLOBAL_number_goals / GLOBAL_best_times(0),
-              one_worker_execution_time * GLOBAL_number_goals / GLOBAL_best_times(0) / number_workers * 100 );
+              one_worker_execution_time * Yap_number_goals / Yap_best_times(0),
+              one_worker_execution_time * Yap_number_goals / Yap_best_times(0) / Yap_number_workers* 100 );
 
-    if (GLOBAL_number_goals >= 3) {
+    if (Yap_number_goals >= 3) {
       fprintf(Yap_stdout, "\n  Average (best three): %f seconds",
-              (GLOBAL_best_times(1) + GLOBAL_best_times(2) + GLOBAL_best_times(3)) / 3);
+              (Yap_best_times(1) + Yap_best_times(2) + Yap_best_times(3)) / 3);
       if (one_worker_execution_time != 0)
         fprintf(Yap_stdout, " --> speedup %f (%6.2f %% ) ]\n\n",
-                one_worker_execution_time * 3 / (GLOBAL_best_times(1) + GLOBAL_best_times(2) + GLOBAL_best_times(3)),
-                one_worker_execution_time * 3 / (GLOBAL_best_times(1) + GLOBAL_best_times(2) + GLOBAL_best_times(3)) / number_workers * 100 );
+                one_worker_execution_time * 3 / (Yap_best_times(1) + Yap_best_times(2) + Yap_best_times(3)),
+                one_worker_execution_time * 3 / (Yap_best_times(1) + Yap_best_times(2) + Yap_best_times(3)) / Yap_number_workers* 100 );
       else fprintf(Yap_stdout, "\n]\n\n");
     } else fprintf(Yap_stdout, "\n]\n\n");
     return (TRUE);
@@ -694,7 +694,7 @@ static Int p_parallel_new_answer( USES_REGS1 ) {
 
 
 static Int p_parallel_yes_answer( USES_REGS1 ) {
-  GLOBAL_answers = YES_ANSWER;
+  Yap_answers = YES_ANSWER;
   return (TRUE);
 }
 
@@ -715,9 +715,9 @@ static Int p_show_statistics_or( USES_REGS1 ) {
   total_bytes += aux_bytes;
 #ifdef SHM_MEMORY_ALLOC_SCHEME
   fprintf(Yap_stdout, "Total memory in use (I+II+III):    %10ld bytes (%ld pages in use)\n",
-          total_bytes, Pg_str_in_use(GLOBAL_PAGES_void));
+          total_bytes, Pg_str_in_use(Yap_pages_void));
   fprintf(Yap_stdout, "Total memory allocated:            %10ld bytes (%ld pages in total)\n",
-          Pg_pg_alloc(GLOBAL_PAGES_void) * Yap_page_size, Pg_pg_alloc(GLOBAL_PAGES_void));
+          Pg_pg_alloc(Yap_pages_void) * Yap_page_size, Pg_pg_alloc(Yap_pages_void));
 #else 
   fprintf(Yap_stdout, "Total memory in use (I+II+III):    %10ld bytes\n", total_bytes);
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
@@ -771,9 +771,9 @@ static Int p_show_statistics_opt( USES_REGS1 ) {
   total_bytes += aux_bytes;
 #ifdef SHM_MEMORY_ALLOC_SCHEME
   fprintf(Yap_stdout, "Total memory in use (I+II+III+IV): %10ld bytes (%ld pages in use)\n",
-          total_bytes, Pg_str_in_use(GLOBAL_PAGES_void));
+          total_bytes, Pg_str_in_use(Yap_pages_void));
   fprintf(Yap_stdout, "Total memory allocated:            %10ld bytes (%ld pages in total)\n",
-          Pg_pg_alloc(GLOBAL_PAGES_void) * Yap_page_size, Pg_pg_alloc(GLOBAL_PAGES_void));
+          Pg_pg_alloc(Yap_pages_void) * Yap_page_size, Pg_pg_alloc(Yap_pages_void));
 #else 
   fprintf(Yap_stdout, "Total memory in use (I+II+III+IV): %10ld bytes\n", total_bytes);
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
@@ -791,99 +791,99 @@ static Int p_get_optyap_statistics( USES_REGS1 ) {
   if (value == 0) {  /* total_memory */
     bytes = 0;
 #ifdef TABLING
-    bytes += Pg_str_in_use(GLOBAL_PAGES_tab_ent) * sizeof(struct table_entry);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_sg_fr) * sizeof(struct subgoal_frame);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_dep_fr) * sizeof(struct dependency_frame);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_sg_node) * sizeof(struct subgoal_trie_node);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_ans_node) * sizeof(struct answer_trie_node);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_sg_hash) * sizeof(struct subgoal_trie_hash);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_ans_hash) * sizeof(struct answer_trie_hash);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_gt_node) * sizeof(struct global_trie_node);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_gt_hash) * sizeof(struct global_trie_hash);
+    bytes += Pg_str_in_use(Yap_pages_tab_ent) * sizeof(struct table_entry);
+    bytes += Pg_str_in_use(Yap_pages_sg_fr) * sizeof(struct subgoal_frame);
+    bytes += Pg_str_in_use(Yap_pages_dep_fr) * sizeof(struct dependency_frame);
+    bytes += Pg_str_in_use(Yap_pages_sg_node) * sizeof(struct subgoal_trie_node);
+    bytes += Pg_str_in_use(Yap_pages_ans_node) * sizeof(struct answer_trie_node);
+    bytes += Pg_str_in_use(Yap_pages_sg_hash) * sizeof(struct subgoal_trie_hash);
+    bytes += Pg_str_in_use(Yap_pages_ans_hash) * sizeof(struct answer_trie_hash);
+    bytes += Pg_str_in_use(Yap_pages_gt_node) * sizeof(struct global_trie_node);
+    bytes += Pg_str_in_use(Yap_pages_gt_hash) * sizeof(struct global_trie_hash);
 #endif /* TABLING */
 #ifdef YAPOR
-    bytes += Pg_str_in_use(GLOBAL_PAGES_or_fr) * sizeof(struct or_frame);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_qg_sol_fr) * sizeof(struct query_goal_solution_frame);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_qg_ans_fr) * sizeof(struct query_goal_answer_frame);
+    bytes += Pg_str_in_use(Yap_pages_or_fr ) * sizeof(struct or_frame);
+    bytes += Pg_str_in_use(Yap_pages_qg_sol_fr ) * sizeof(struct query_goal_solution_frame);
+    bytes += Pg_str_in_use(Yap_pages_qg_ans_fr) * sizeof(struct query_goal_answer_frame);
 #endif /* YAPOR */
 #if defined(YAPOR) && defined(TABLING)
-    bytes += Pg_str_in_use(GLOBAL_PAGES_susp_fr) * sizeof(struct suspension_frame);
+    bytes += Pg_str_in_use(Yap_pages_susp_fr) * sizeof(struct suspension_frame);
 #ifdef TABLING_INNER_CUTS
-    bytes += Pg_str_in_use(GLOBAL_PAGES_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame);
-    bytes += Pg_str_in_use(GLOBAL_PAGES_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame);
+    bytes += Pg_str_in_use(Yap_pages_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame);
+    bytes += Pg_str_in_use(Yap_pages_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame);
 #endif /* TABLING_INNER_CUTS */
 #endif /* YAPOR && TABLING */
 #ifdef SHM_MEMORY_ALLOC_SCHEME
-    structs = Pg_pg_alloc(GLOBAL_PAGES_void) * Yap_page_size;
+    structs = Pg_pg_alloc(Yap_pages_void) * Yap_page_size;
 #else
     structs = bytes;
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
   }
 #ifdef TABLING
   if (value == 1) {  /* table_entries */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_tab_ent) * sizeof(struct table_entry);
-    structs = Pg_str_in_use(GLOBAL_PAGES_tab_ent);
+    bytes = Pg_str_in_use(Yap_pages_tab_ent) * sizeof(struct table_entry);
+    structs = Pg_str_in_use(Yap_pages_tab_ent);
   }
   if (value == 2) {  /* subgoal_frames */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_sg_fr) * sizeof(struct subgoal_frame);
-    structs = Pg_str_in_use(GLOBAL_PAGES_sg_fr);
+    bytes = Pg_str_in_use(Yap_pages_sg_fr) * sizeof(struct subgoal_frame);
+    structs = Pg_str_in_use(Yap_pages_sg_fr);
   }
   if (value == 3) {  /* dependency_frames */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_dep_fr) * sizeof(struct dependency_frame);
-    structs = Pg_str_in_use(GLOBAL_PAGES_dep_fr);
+    bytes = Pg_str_in_use(Yap_pages_dep_fr) * sizeof(struct dependency_frame);
+    structs = Pg_str_in_use(Yap_pages_dep_fr);
   }
   if (value == 6) {  /* subgoal_trie_nodes */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_sg_node) * sizeof(struct subgoal_trie_node);
-    structs = Pg_str_in_use(GLOBAL_PAGES_sg_node);
+    bytes = Pg_str_in_use(Yap_pages_sg_node) * sizeof(struct subgoal_trie_node);
+    structs = Pg_str_in_use(Yap_pages_sg_node);
   }
   if (value == 7) {  /* answer_trie_nodes */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_ans_node) * sizeof(struct answer_trie_node);
-    structs = Pg_str_in_use(GLOBAL_PAGES_ans_node);
+    bytes = Pg_str_in_use(Yap_pages_ans_node) * sizeof(struct answer_trie_node);
+    structs = Pg_str_in_use(Yap_pages_ans_node);
   }
   if (value == 8) {  /* subgoal_trie_hashes */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_sg_hash) * sizeof(struct subgoal_trie_hash);
-    structs = Pg_str_in_use(GLOBAL_PAGES_sg_hash);
+    bytes = Pg_str_in_use(Yap_pages_sg_hash) * sizeof(struct subgoal_trie_hash);
+    structs = Pg_str_in_use(Yap_pages_sg_hash);
   }
   if (value == 9) {  /* answer_trie_hashes */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_ans_hash) * sizeof(struct answer_trie_hash);
-    structs = Pg_str_in_use(GLOBAL_PAGES_ans_hash);
+    bytes = Pg_str_in_use(Yap_pages_ans_hash) * sizeof(struct answer_trie_hash);
+    structs = Pg_str_in_use(Yap_pages_ans_hash);
   }
   if (value == 10) {  /* global_trie_nodes */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_gt_node) * sizeof(struct global_trie_node);
-    structs = Pg_str_in_use(GLOBAL_PAGES_gt_node);
+    bytes = Pg_str_in_use(Yap_pages_gt_node) * sizeof(struct global_trie_node);
+    structs = Pg_str_in_use(Yap_pages_gt_node);
   }
   if (value == 11) {  /* global_trie_hashes */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_gt_hash) * sizeof(struct global_trie_hash);
-    structs = Pg_str_in_use(GLOBAL_PAGES_gt_hash);
+    bytes = Pg_str_in_use(Yap_pages_gt_hash) * sizeof(struct global_trie_hash);
+    structs = Pg_str_in_use(Yap_pages_gt_hash);
   }
 #endif /* TABLING */
 #ifdef YAPOR
   if (value == 4) {  /* or_frames */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_or_fr) * sizeof(struct or_frame);
-    structs = Pg_str_in_use(GLOBAL_PAGES_or_fr);
+    bytes = Pg_str_in_use(Yap_pages_or_fr ) * sizeof(struct or_frame);
+    structs = Pg_str_in_use(Yap_pages_or_fr );
   }
   if (value == 12) {  /* query_goal_solution_frames */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_qg_sol_fr) * sizeof(struct query_goal_solution_frame);
-    structs = Pg_str_in_use(GLOBAL_PAGES_qg_sol_fr);
+    bytes = Pg_str_in_use(Yap_pages_qg_sol_fr ) * sizeof(struct query_goal_solution_frame);
+    structs = Pg_str_in_use(Yap_pages_qg_sol_fr );
   }
   if (value == 13) {  /* query_goal_answer_frames */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_qg_ans_fr) * sizeof(struct query_goal_answer_frame);
-    structs = Pg_str_in_use(GLOBAL_PAGES_qg_ans_fr);
+    bytes = Pg_str_in_use(Yap_pages_qg_ans_fr) * sizeof(struct query_goal_answer_frame);
+    structs = Pg_str_in_use(Yap_pages_qg_ans_fr);
   }
 #endif /* YAPOR */
 #if defined(YAPOR) && defined(TABLING)
   if (value == 5) {  /* suspension_frames */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_susp_fr) * sizeof(struct suspension_frame);
-    structs = Pg_str_in_use(GLOBAL_PAGES_susp_fr);
+    bytes = Pg_str_in_use(Yap_pages_susp_fr) * sizeof(struct suspension_frame);
+    structs = Pg_str_in_use(Yap_pages_susp_fr);
   }
 #ifdef TABLING_INNER_CUTS
   if (value == 14) {  /* table_subgoal_solution_frames */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame);
-    structs = Pg_str_in_use(GLOBAL_PAGES_tg_sol_fr);
+    bytes = Pg_str_in_use(Yap_pages_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame);
+    structs = Pg_str_in_use(Yap_pages_tg_sol_fr);
   }
   if (value == 15) {  /* table_subgoal_answer_frames */
-    bytes = Pg_str_in_use(GLOBAL_PAGES_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame);
-    structs = Pg_str_in_use(GLOBAL_PAGES_tg_ans_fr);
+    bytes = Pg_str_in_use(Yap_pages_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame);
+    structs = Pg_str_in_use(Yap_pages_tg_ans_fr);
   }
 #endif /* TABLING_INNER_CUTS */
 #endif /* YAPOR && TABLING */
@@ -938,12 +938,12 @@ static inline void show_answers(void) {
       aux_answer2 = aux_answer1;
       aux_answer1 = AnsFr_next(aux_answer1);
       FREE_QG_ANSWER_FRAME(aux_answer2);
-      GLOBAL_answers++;
+      Yap_answers++;
     }
     FREE_QG_SOLUTION_FRAME(OrFr_qg_solutions(LOCAL_top_or_fr));
     OrFr_qg_solutions(LOCAL_top_or_fr) = NULL;
   }
-  switch(GLOBAL_answers) {
+  switch(Yap_answers) {
     case YES_ANSWER:
       fprintf(Yap_stderr, "[ yes");
       break;
@@ -954,27 +954,27 @@ static inline void show_answers(void) {
       fprintf(Yap_stderr, "[ 1 answer found");
       break;
     default:
-         fprintf(Yap_stderr, "[ %d answers found", GLOBAL_answers);
+         fprintf(Yap_stderr, "[ %d answers found", Yap_answers);
       break;
   }
-  fprintf(Yap_stderr, " (in %f seconds) ]\n\n", GLOBAL_execution_time);
+  fprintf(Yap_stderr, " (in %f seconds) ]\n\n", Yap_execution_time);
 
-  if (GLOBAL_performance_mode == PERFORMANCE_ON) {
-    for (i = GLOBAL_number_goals; i > 0; i--) {
-      if (GLOBAL_best_times(i) > GLOBAL_execution_time) {
+  if (Yap_performance_mode == PERFORMANCE_ON) {
+    for (i = Yap_number_goals; i > 0; i--) {
+      if (Yap_best_times(i) > Yap_execution_time) {
         if (i + 1 < MAX_BEST_TIMES)
-          GLOBAL_best_times(i + 1) = GLOBAL_best_times(i);
+          Yap_best_times(i + 1) = Yap_best_times(i);
         else {
-          GLOBAL_best_times(0) -= GLOBAL_best_times(i);
+          Yap_best_times(0) -= Yap_best_times(i);
         }
       }
       else break;
     }
     if (i + 1 < MAX_BEST_TIMES) {
-      GLOBAL_best_times(0) += GLOBAL_execution_time;
-      GLOBAL_best_times(i + 1) = GLOBAL_execution_time;
-      if (GLOBAL_number_goals + 1 < MAX_BEST_TIMES)
-        GLOBAL_number_goals++;
+      Yap_best_times(0) += Yap_execution_time;
+      Yap_best_times(i + 1) = Yap_execution_time;
+      if (Yap_number_goals + 1 < MAX_BEST_TIMES)
+        Yap_number_goals++;
     }
   }
 
@@ -1031,7 +1031,7 @@ static inline long show_statistics_table_entries(void) {
   tab_ent_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_tab_ent);
+  pg_hd = Pg_free_pg(Yap_pages_tab_ent);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1040,15 +1040,15 @@ static inline long show_statistics_table_entries(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  TABLING_ERROR_CHECKING(statistics_table_entries, Pg_str_free(GLOBAL_PAGES_tab_ent) != cont);
+  TABLING_ERROR_CHECKING(statistics_table_entries, Pg_str_free(Yap_pages_tab_ent) != cont);
 #endif /* DEBUG_TABLING */
   fprintf(Yap_stdout, "  Table entries:                   %10ld bytes (%ld pages and %ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_tab_ent) * sizeof(struct table_entry), Pg_pg_alloc(GLOBAL_PAGES_tab_ent), Pg_str_in_use(GLOBAL_PAGES_tab_ent));
+          Pg_str_in_use(Yap_pages_tab_ent) * sizeof(struct table_entry), Pg_pg_alloc(Yap_pages_tab_ent), Pg_str_in_use(Yap_pages_tab_ent));
 #else
   fprintf(Yap_stdout, "  Table entries:                   %10ld bytes (%ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_tab_ent) * sizeof(struct table_entry), Pg_str_in_use(GLOBAL_PAGES_tab_ent));
+          Pg_str_in_use(Yap_pages_tab_ent) * sizeof(struct table_entry), Pg_str_in_use(Yap_pages_tab_ent));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_tab_ent) * sizeof(struct table_entry);
+  return Pg_str_in_use(Yap_pages_tab_ent) * sizeof(struct table_entry);
 }
 
 
@@ -1059,7 +1059,7 @@ static inline long show_statistics_subgoal_frames(void) {
   sg_fr_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_sg_fr);
+  pg_hd = Pg_free_pg(Yap_pages_sg_fr);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1068,15 +1068,15 @@ static inline long show_statistics_subgoal_frames(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  TABLING_ERROR_CHECKING(statistics_subgoal_frames, Pg_str_free(GLOBAL_PAGES_sg_fr) != cont);
+  TABLING_ERROR_CHECKING(statistics_subgoal_frames, Pg_str_free(Yap_pages_sg_fr) != cont);
 #endif /* DEBUG_TABLING */
   fprintf(Yap_stdout, "  Subgoal frames:                  %10ld bytes (%ld pages and %ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_sg_fr) * sizeof(struct subgoal_frame), Pg_pg_alloc(GLOBAL_PAGES_sg_fr), Pg_str_in_use(GLOBAL_PAGES_sg_fr));
+          Pg_str_in_use(Yap_pages_sg_fr) * sizeof(struct subgoal_frame), Pg_pg_alloc(Yap_pages_sg_fr), Pg_str_in_use(Yap_pages_sg_fr));
 #else
   fprintf(Yap_stdout, "  Subgoal frames:                  %10ld bytes (%ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_sg_fr) * sizeof(struct subgoal_frame), Pg_str_in_use(GLOBAL_PAGES_sg_fr));
+          Pg_str_in_use(Yap_pages_sg_fr) * sizeof(struct subgoal_frame), Pg_str_in_use(Yap_pages_sg_fr));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_sg_fr) * sizeof(struct subgoal_frame);
+  return Pg_str_in_use(Yap_pages_sg_fr) * sizeof(struct subgoal_frame);
 }
 
 
@@ -1087,7 +1087,7 @@ static inline long show_statistics_dependency_frames(void) {
   dep_fr_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_dep_fr);
+  pg_hd = Pg_free_pg(Yap_pages_dep_fr);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1096,15 +1096,15 @@ static inline long show_statistics_dependency_frames(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  TABLING_ERROR_CHECKING(statistics_dependency_frames, Pg_str_free(GLOBAL_PAGES_dep_fr) != cont);
+  TABLING_ERROR_CHECKING(statistics_dependency_frames, Pg_str_free(Yap_pages_dep_fr) != cont);
 #endif /* DEBUG_TABLING */
   fprintf(Yap_stdout, "  Dependency frames:               %10ld bytes (%ld pages and %ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_dep_fr) * sizeof(struct dependency_frame), Pg_pg_alloc(GLOBAL_PAGES_dep_fr), Pg_str_in_use(GLOBAL_PAGES_dep_fr));
+          Pg_str_in_use(Yap_pages_dep_fr) * sizeof(struct dependency_frame), Pg_pg_alloc(Yap_pages_dep_fr), Pg_str_in_use(Yap_pages_dep_fr));
 #else
   fprintf(Yap_stdout, "  Dependency frames:               %10ld bytes (%ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_dep_fr) * sizeof(struct dependency_frame), Pg_str_in_use(GLOBAL_PAGES_dep_fr));
+          Pg_str_in_use(Yap_pages_dep_fr) * sizeof(struct dependency_frame), Pg_str_in_use(Yap_pages_dep_fr));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_dep_fr) * sizeof(struct dependency_frame);
+  return Pg_str_in_use(Yap_pages_dep_fr) * sizeof(struct dependency_frame);
 }
 
 
@@ -1115,7 +1115,7 @@ static inline long show_statistics_subgoal_trie_nodes(void) {
   sg_node_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_sg_node);
+  pg_hd = Pg_free_pg(Yap_pages_sg_node);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1124,15 +1124,15 @@ static inline long show_statistics_subgoal_trie_nodes(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  TABLING_ERROR_CHECKING(statistics_subgoal_trie_nodes, Pg_str_free(GLOBAL_PAGES_sg_node) != cont);
+  TABLING_ERROR_CHECKING(statistics_subgoal_trie_nodes, Pg_str_free(Yap_pages_sg_node) != cont);
 #endif /* DEBUG_TABLING */
   fprintf(Yap_stdout, "  Subgoal trie nodes:              %10ld bytes (%ld pages and %ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_sg_node) * sizeof(struct subgoal_trie_node), Pg_pg_alloc(GLOBAL_PAGES_sg_node), Pg_str_in_use(GLOBAL_PAGES_sg_node));
+          Pg_str_in_use(Yap_pages_sg_node) * sizeof(struct subgoal_trie_node), Pg_pg_alloc(Yap_pages_sg_node), Pg_str_in_use(Yap_pages_sg_node));
 #else
   fprintf(Yap_stdout, "  Subgoal trie nodes:              %10ld bytes (%ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_sg_node) * sizeof(struct subgoal_trie_node), Pg_str_in_use(GLOBAL_PAGES_sg_node));
+          Pg_str_in_use(Yap_pages_sg_node) * sizeof(struct subgoal_trie_node), Pg_str_in_use(Yap_pages_sg_node));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_sg_node) * sizeof(struct subgoal_trie_node);
+  return Pg_str_in_use(Yap_pages_sg_node) * sizeof(struct subgoal_trie_node);
 }
 
 
@@ -1143,7 +1143,7 @@ static inline long show_statistics_answer_trie_nodes(void) {
   ans_node_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_ans_node);
+  pg_hd = Pg_free_pg(Yap_pages_ans_node);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1152,15 +1152,15 @@ static inline long show_statistics_answer_trie_nodes(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  TABLING_ERROR_CHECKING(statistics_answer_trie_nodes, Pg_str_free(GLOBAL_PAGES_ans_node) != cont);
+  TABLING_ERROR_CHECKING(statistics_answer_trie_nodes, Pg_str_free(Yap_pages_ans_node) != cont);
 #endif /* DEBUG_TABLING */
   fprintf(Yap_stdout, "  Answer trie nodes:               %10ld bytes (%ld pages and %ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_ans_node) * sizeof(struct answer_trie_node), Pg_pg_alloc(GLOBAL_PAGES_ans_node), Pg_str_in_use(GLOBAL_PAGES_ans_node));
+          Pg_str_in_use(Yap_pages_ans_node) * sizeof(struct answer_trie_node), Pg_pg_alloc(Yap_pages_ans_node), Pg_str_in_use(Yap_pages_ans_node));
 #else
   fprintf(Yap_stdout, "  Answer trie nodes:               %10ld bytes (%ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_ans_node) * sizeof(struct answer_trie_node), Pg_str_in_use(GLOBAL_PAGES_ans_node));
+          Pg_str_in_use(Yap_pages_ans_node) * sizeof(struct answer_trie_node), Pg_str_in_use(Yap_pages_ans_node));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_ans_node) * sizeof(struct answer_trie_node);
+  return Pg_str_in_use(Yap_pages_ans_node) * sizeof(struct answer_trie_node);
 }
 
 
@@ -1171,7 +1171,7 @@ static inline long show_statistics_subgoal_trie_hashes(void) {
   sg_hash_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_sg_hash);
+  pg_hd = Pg_free_pg(Yap_pages_sg_hash);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1180,15 +1180,15 @@ static inline long show_statistics_subgoal_trie_hashes(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  TABLING_ERROR_CHECKING(statistics_subgoal_trie_hashes, Pg_str_free(GLOBAL_PAGES_sg_hash) != cont);
+  TABLING_ERROR_CHECKING(statistics_subgoal_trie_hashes, Pg_str_free(Yap_pages_sg_hash) != cont);
 #endif /* DEBUG_TABLING */
   fprintf(Yap_stdout, "  Subgoal trie hashes:             %10ld bytes (%ld pages and %ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_sg_hash) * sizeof(struct subgoal_trie_hash), Pg_pg_alloc(GLOBAL_PAGES_sg_hash), Pg_str_in_use(GLOBAL_PAGES_sg_hash));
+          Pg_str_in_use(Yap_pages_sg_hash) * sizeof(struct subgoal_trie_hash), Pg_pg_alloc(Yap_pages_sg_hash), Pg_str_in_use(Yap_pages_sg_hash));
 #else
   fprintf(Yap_stdout, "  Subgoal trie hashes:             %10ld bytes (%ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_sg_hash) * sizeof(struct subgoal_trie_hash), Pg_str_in_use(GLOBAL_PAGES_sg_hash));
+          Pg_str_in_use(Yap_pages_sg_hash) * sizeof(struct subgoal_trie_hash), Pg_str_in_use(Yap_pages_sg_hash));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_sg_hash) * sizeof(struct subgoal_trie_hash);
+  return Pg_str_in_use(Yap_pages_sg_hash) * sizeof(struct subgoal_trie_hash);
 }
 
 
@@ -1199,7 +1199,7 @@ static inline long show_statistics_answer_trie_hashes(void) {
   ans_hash_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_ans_hash);
+  pg_hd = Pg_free_pg(Yap_pages_ans_hash);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1208,15 +1208,15 @@ static inline long show_statistics_answer_trie_hashes(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  TABLING_ERROR_CHECKING(statistics_answer_trie_hashes, Pg_str_free(GLOBAL_PAGES_ans_hash) != cont);
+  TABLING_ERROR_CHECKING(statistics_answer_trie_hashes, Pg_str_free(Yap_pages_ans_hash) != cont);
 #endif /* DEBUG_TABLING */
   fprintf(Yap_stdout, "  Answer trie hashes:              %10ld bytes (%ld pages and %ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_ans_hash) * sizeof(struct answer_trie_hash), Pg_pg_alloc(GLOBAL_PAGES_ans_hash), Pg_str_in_use(GLOBAL_PAGES_ans_hash));
+          Pg_str_in_use(Yap_pages_ans_hash) * sizeof(struct answer_trie_hash), Pg_pg_alloc(Yap_pages_ans_hash), Pg_str_in_use(Yap_pages_ans_hash));
 #else
   fprintf(Yap_stdout, "  Answer trie hashes:              %10ld bytes (%ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_ans_hash) * sizeof(struct answer_trie_hash), Pg_str_in_use(GLOBAL_PAGES_ans_hash));
+          Pg_str_in_use(Yap_pages_ans_hash) * sizeof(struct answer_trie_hash), Pg_str_in_use(Yap_pages_ans_hash));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_ans_hash) * sizeof(struct answer_trie_hash);
+  return Pg_str_in_use(Yap_pages_ans_hash) * sizeof(struct answer_trie_hash);
 }
 
 
@@ -1227,7 +1227,7 @@ static inline long show_statistics_global_trie_nodes(void) {
   gt_node_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_gt_node);
+  pg_hd = Pg_free_pg(Yap_pages_gt_node);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1236,15 +1236,15 @@ static inline long show_statistics_global_trie_nodes(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  TABLING_ERROR_CHECKING(statistics_global_trie_nodes, Pg_str_free(GLOBAL_PAGES_gt_node) != cont);
+  TABLING_ERROR_CHECKING(statistics_global_trie_nodes, Pg_str_free(Yap_pages_gt_node) != cont);
 #endif /* DEBUG_TABLING */
   fprintf(Yap_stdout, "  Global trie nodes:               %10ld bytes (%ld pages and %ld structs in use)\n", 
-	  Pg_str_in_use(GLOBAL_PAGES_gt_node) * sizeof(struct global_trie_node), Pg_pg_alloc(GLOBAL_PAGES_gt_node), Pg_str_in_use(GLOBAL_PAGES_gt_node));
+	  Pg_str_in_use(Yap_pages_gt_node) * sizeof(struct global_trie_node), Pg_pg_alloc(Yap_pages_gt_node), Pg_str_in_use(Yap_pages_gt_node));
 #else
   fprintf(Yap_stdout, "  Global trie nodes:               %10ld bytes (%ld structs in use)\n", 
-	  Pg_str_in_use(GLOBAL_PAGES_gt_node) * sizeof(struct global_trie_node), Pg_str_in_use(GLOBAL_PAGES_gt_node));
+	  Pg_str_in_use(Yap_pages_gt_node) * sizeof(struct global_trie_node), Pg_str_in_use(Yap_pages_gt_node));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_gt_node) * sizeof(struct global_trie_node);
+  return Pg_str_in_use(Yap_pages_gt_node) * sizeof(struct global_trie_node);
 }
 
 
@@ -1255,7 +1255,7 @@ static inline long show_statistics_global_trie_hashes(void) {
   gt_hash_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_gt_hash);
+  pg_hd = Pg_free_pg(Yap_pages_gt_hash);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1264,15 +1264,15 @@ static inline long show_statistics_global_trie_hashes(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  TABLING_ERROR_CHECKING(statistics_global_trie_hashes, Pg_str_free(GLOBAL_PAGES_gt_hash) != cont);
+  TABLING_ERROR_CHECKING(statistics_global_trie_hashes, Pg_str_free(Yap_pages_gt_hash) != cont);
 #endif /* DEBUG_TABLING */
   fprintf(Yap_stdout, "  Global trie hashes:              %10ld bytes (%ld pages and %ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_gt_hash) * sizeof(struct global_trie_hash), Pg_pg_alloc(GLOBAL_PAGES_gt_hash), Pg_str_in_use(GLOBAL_PAGES_gt_hash));
+          Pg_str_in_use(Yap_pages_gt_hash) * sizeof(struct global_trie_hash), Pg_pg_alloc(Yap_pages_gt_hash), Pg_str_in_use(Yap_pages_gt_hash));
 #else
   fprintf(Yap_stdout, "  Global trie hashes:              %10ld bytes (%ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_gt_hash) * sizeof(struct global_trie_hash), Pg_str_in_use(GLOBAL_PAGES_gt_hash));
+          Pg_str_in_use(Yap_pages_gt_hash) * sizeof(struct global_trie_hash), Pg_str_in_use(Yap_pages_gt_hash));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_gt_hash) * sizeof(struct global_trie_hash);
+  return Pg_str_in_use(Yap_pages_gt_hash) * sizeof(struct global_trie_hash);
 }
 #endif /* TABLING */
 
@@ -1285,7 +1285,7 @@ static inline long show_statistics_or_frames(void) {
   or_fr_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_or_fr);
+  pg_hd = Pg_free_pg(Yap_pages_or_fr );
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1294,15 +1294,15 @@ static inline long show_statistics_or_frames(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  YAPOR_ERROR_CHECKING(statistics_or_frames, Pg_str_free(GLOBAL_PAGES_or_fr) != cont);
+  YAPOR_ERROR_CHECKING(statistics_or_frames, Pg_str_free(Yap_pages_or_fr ) != cont);
 #endif /* DEBUG_YAPOR */
   fprintf(Yap_stdout, "  Or-frames:                       %10ld bytes (%ld pages and %ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_or_fr) * sizeof(struct or_frame), Pg_pg_alloc(GLOBAL_PAGES_or_fr), Pg_str_in_use(GLOBAL_PAGES_or_fr));
+          Pg_str_in_use(Yap_pages_or_fr ) * sizeof(struct or_frame), Pg_pg_alloc(Yap_pages_or_fr ), Pg_str_in_use(Yap_pages_or_fr ));
 #else
   fprintf(Yap_stdout, "  Or-frames:                       %10ld bytes (%ld structs in use)\n", 
-          Pg_str_in_use(GLOBAL_PAGES_or_fr) * sizeof(struct or_frame), Pg_str_in_use(GLOBAL_PAGES_or_fr));
+          Pg_str_in_use(Yap_pages_or_fr ) * sizeof(struct or_frame), Pg_str_in_use(Yap_pages_or_fr ));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_or_fr) * sizeof(struct or_frame);
+  return Pg_str_in_use(Yap_pages_or_fr ) * sizeof(struct or_frame);
 }
 
 
@@ -1313,7 +1313,7 @@ static inline long show_statistics_query_goal_solution_frames(void) {
   qg_sol_fr_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_qg_sol_fr);
+  pg_hd = Pg_free_pg(Yap_pages_qg_sol_fr );
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1322,15 +1322,15 @@ static inline long show_statistics_query_goal_solution_frames(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  YAPOR_ERROR_CHECKING(statistics_query_goal_solution_frames, Pg_str_free(GLOBAL_PAGES_qg_sol_fr) != cont);
+  YAPOR_ERROR_CHECKING(statistics_query_goal_solution_frames, Pg_str_free(Yap_pages_qg_sol_fr ) != cont);
 #endif /* DEBUG_YAPOR */
   fprintf(Yap_stdout, "  Query goal solution frames:      %10ld bytes (%ld pages and %ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_qg_sol_fr) * sizeof(struct query_goal_solution_frame), Pg_pg_alloc(GLOBAL_PAGES_qg_sol_fr), Pg_str_in_use(GLOBAL_PAGES_qg_sol_fr));
+          Pg_str_in_use(Yap_pages_qg_sol_fr ) * sizeof(struct query_goal_solution_frame), Pg_pg_alloc(Yap_pages_qg_sol_fr ), Pg_str_in_use(Yap_pages_qg_sol_fr ));
 #else
   fprintf(Yap_stdout, "  Query goal solution frames:      %10ld bytes (%ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_qg_sol_fr) * sizeof(struct query_goal_solution_frame), Pg_str_in_use(GLOBAL_PAGES_qg_sol_fr));
+          Pg_str_in_use(Yap_pages_qg_sol_fr ) * sizeof(struct query_goal_solution_frame), Pg_str_in_use(Yap_pages_qg_sol_fr ));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_qg_sol_fr) * sizeof(struct query_goal_solution_frame);
+  return Pg_str_in_use(Yap_pages_qg_sol_fr ) * sizeof(struct query_goal_solution_frame);
 }
 
 
@@ -1341,7 +1341,7 @@ static inline long show_statistics_query_goal_answer_frames(void) {
   qg_ans_fr_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_qg_ans_fr);
+  pg_hd = Pg_free_pg(Yap_pages_qg_ans_fr);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1350,15 +1350,15 @@ static inline long show_statistics_query_goal_answer_frames(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  YAPOR_ERROR_CHECKING(statistics_query_goal_answer_frames, Pg_str_free(GLOBAL_PAGES_qg_ans_fr) != cont);
+  YAPOR_ERROR_CHECKING(statistics_query_goal_answer_frames, Pg_str_free(Yap_pages_qg_ans_fr) != cont);
 #endif /* DEBUG_YAPOR */
   fprintf(Yap_stdout, "  Query goal answer frames:        %10ld bytes (%ld pages and %ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_qg_ans_fr) * sizeof(struct query_goal_answer_frame), Pg_pg_alloc(GLOBAL_PAGES_qg_ans__fr), Pg_str_in_use(GLOBAL_PAGES_qg_ans_fr));
+          Pg_str_in_use(Yap_pages_qg_ans_fr) * sizeof(struct query_goal_answer_frame), Pg_pg_alloc(Yap_pages_qg_ans__fr), Pg_str_in_use(Yap_pages_qg_ans_fr));
 #else
   fprintf(Yap_stdout, "  Query goal answer frames:        %10ld bytes (%ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_qg_ans_fr) * sizeof(struct query_goal_answer_frame), Pg_str_in_use(GLOBAL_PAGES_qg_ans_fr));
+          Pg_str_in_use(Yap_pages_qg_ans_fr) * sizeof(struct query_goal_answer_frame), Pg_str_in_use(Yap_pages_qg_ans_fr));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_qg_ans_fr) * sizeof(struct query_goal_answer_frame);
+  return Pg_str_in_use(Yap_pages_qg_ans_fr) * sizeof(struct query_goal_answer_frame);
 }
 #endif /* YAPOR */
 
@@ -1371,7 +1371,7 @@ static inline long show_statistics_suspension_frames(void) {
   susp_fr_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_susp_fr);
+  pg_hd = Pg_free_pg(Yap_pages_susp_fr);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1380,15 +1380,15 @@ static inline long show_statistics_suspension_frames(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  OPTYAP_ERROR_CHECKING(statistics_suspension_frames, Pg_str_free(GLOBAL_PAGES_susp_fr) != cont);
+  OPTYAP_ERROR_CHECKING(statistics_suspension_frames, Pg_str_free(Yap_pages_susp_fr) != cont);
 #endif /* DEBUG_OPTYAP */
   fprintf(Yap_stdout, "  Suspension frames:               %10ld bytes (%ld pages and %ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_susp_fr) * sizeof(struct suspension_frame), Pg_pg_alloc(GLOBAL_PAGES_susp_fr), Pg_str_in_use(GLOBAL_PAGES_susp_fr));
+          Pg_str_in_use(Yap_pages_susp_fr) * sizeof(struct suspension_frame), Pg_pg_alloc(Yap_pages_susp_fr), Pg_str_in_use(Yap_pages_susp_fr));
 #else
   fprintf(Yap_stdout, "  Suspension frames:               %10ld bytes (%ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_susp_fr) * sizeof(struct suspension_frame), Pg_str_in_use(GLOBAL_PAGES_susp_fr));
+          Pg_str_in_use(Yap_pages_susp_fr) * sizeof(struct suspension_frame), Pg_str_in_use(Yap_pages_susp_fr));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_susp_fr) * sizeof(struct suspension_frame);
+  return Pg_str_in_use(Yap_pages_susp_fr) * sizeof(struct suspension_frame);
 }
 
 
@@ -1400,7 +1400,7 @@ static inline long show_statistics_table_subgoal_solution_frames(void) {
   tg_sol_fr_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_tg_sol_fr);
+  pg_hd = Pg_free_pg(Yap_pages_tg_sol_fr);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1409,15 +1409,15 @@ static inline long show_statistics_table_subgoal_solution_frames(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  OPTYAP_ERROR_CHECKING(statistics_table_subgoal_solution_frames, Pg_str_free(GLOBAL_PAGES_tg_sol_fr) != cont);
+  OPTYAP_ERROR_CHECKING(statistics_table_subgoal_solution_frames, Pg_str_free(Yap_pages_tg_sol_fr) != cont);
 #endif /* DEBUG_OPTYAP */
   fprintf(Yap_stdout, "  Table subgoal solution frames:   %10ld bytes (%ld pages and %ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame), Pg_pg_alloc(GLOBAL_PAGES_tg_sol_fr), Pg_str_in_use(GLOBAL_PAGES_tg_sol_fr));
+          Pg_str_in_use(Yap_pages_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame), Pg_pg_alloc(Yap_pages_tg_sol_fr), Pg_str_in_use(Yap_pages_tg_sol_fr));
 #else
   fprintf(Yap_stdout, "  Table subgoal solution frames:   %10ld bytes (%ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame), Pg_str_in_use(GLOBAL_PAGES_tg_sol_fr));
+          Pg_str_in_use(Yap_pages_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame), Pg_str_in_use(Yap_pages_tg_sol_fr));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame);
+  return Pg_str_in_use(Yap_pages_tg_sol_fr) * sizeof(struct table_subgoal_solution_frame);
 }
 
 
@@ -1428,7 +1428,7 @@ static inline long show_statistics_table_subgoal_answer_frames(void) {
   tg_ans_fr_ptr aux_ptr;
   long cont = 0;
 
-  pg_hd = Pg_free_pg(GLOBAL_PAGES_tg_ans_fr);
+  pg_hd = Pg_free_pg(Yap_pages_tg_ans_fr);
   while (pg_hd) {
     aux_ptr = PgHd_free_str(pg_hd);
     while (aux_ptr) {
@@ -1437,15 +1437,15 @@ static inline long show_statistics_table_subgoal_answer_frames(void) {
     }
     pg_hd = PgHd_next(pg_hd);
   }
-  OPTYAP_ERROR_CHECKING(statistics_table_subgoal_answer_frames, Pg_str_free(GLOBAL_PAGES_tg_ans_fr) != cont);
+  OPTYAP_ERROR_CHECKING(statistics_table_subgoal_answer_frames, Pg_str_free(Yap_pages_tg_ans_fr) != cont);
 #endif /* DEBUG_OPTYAP */
   fprintf(Yap_stdout, "  Table subgoal answer frames:     %10ld bytes (%ld pages and %ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame), Pg_pg_alloc(GLOBAL_PAGES_tg_ans_fr), Pg_str_in_use(GLOBAL_PAGES_tg_ans_fr));
+          Pg_str_in_use(Yap_pages_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame), Pg_pg_alloc(Yap_pages_tg_ans_fr), Pg_str_in_use(Yap_pages_tg_ans_fr));
 #else
   fprintf(Yap_stdout, "  Table subgoal answer frames:     %10ld bytes (%ld structs in use)\n",
-          Pg_str_in_use(GLOBAL_PAGES_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame), Pg_str_in_use(GLOBAL_PAGES_tg_ans_fr));
+          Pg_str_in_use(Yap_pages_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame), Pg_str_in_use(Yap_pages_tg_ans_fr));
 #endif /* SHM_MEMORY_ALLOC_SCHEME */
-  return Pg_str_in_use(GLOBAL_PAGES_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame);
+  return Pg_str_in_use(Yap_pages_tg_ans_fr) * sizeof(struct table_subgoal_answer_frame);
 }
 #endif /* TABLING_INNER_CUTS */
 #endif /* YAPOR && TABLING */
diff --git a/OPTYap/opt.proto.h b/OPTYap/opt.proto.h
index ac73e3c55..8af6b12b4 100644
--- a/OPTYap/opt.proto.h
+++ b/OPTYap/opt.proto.h
@@ -33,7 +33,7 @@ void remap_memory(void);
 **      opt.init.c      **
 *************************/
 
-void Yap_init_global(int, int, int, int);
+void Yap_init_optyap_global(int, int, int, int);
 void Yap_init_local(void);
 void make_root_frames(void);
 #ifdef YAPOR
@@ -90,7 +90,7 @@ void resume_suspension_frame(susp_fr_ptr, or_fr_ptr);
 
 
 /**************************
-**      or.engine.c      **
+**      or.copy_engine.c      **
 **************************/
 
 #ifdef YAPOR
diff --git a/OPTYap/opt.structs.h b/OPTYap/opt.structs.h
index 0cfdc3461..f45679095 100644
--- a/OPTYap/opt.structs.h
+++ b/OPTYap/opt.structs.h
@@ -157,10 +157,10 @@ struct global_locks {
 
 
 /*********************************
-**      Struct global_data      **
+*   Struct optyap_global_data   **
 *********************************/
 
-struct global_data{
+struct optyap_global_data{
   /* global data related to memory management */
   struct global_pages pages;
 
@@ -170,9 +170,9 @@ struct global_data{
   int delayed_release_load;
   int number_workers;
   int worker_pid[MAX_WORKERS];
-#ifdef ACOW
+#ifdef YAPOR_COW
   int master_worker;
-#endif /* ACOW */
+#endif /* YAPOR_COW */
 
   /* global data related to or-performance */
   realtime execution_time;
@@ -223,72 +223,72 @@ struct global_data{
 #endif /* TABLING */
 };
 
-#define GLOBAL_MAX_PAGES                        (GLOBAL.pages.max_pages)
-#define GLOBAL_PAGES_void                       (GLOBAL.pages.void_pages)
-#define GLOBAL_PAGES_or_fr                      (GLOBAL.pages.or_frame_pages)
-#define GLOBAL_PAGES_qg_sol_fr                  (GLOBAL.pages.query_goal_solution_frame_pages)
-#define GLOBAL_PAGES_qg_ans_fr                  (GLOBAL.pages.query_goal_answer_frame_pages)
-#define GLOBAL_PAGES_tg_sol_fr                  (GLOBAL.pages.table_subgoal_solution_frame_pages)
-#define GLOBAL_PAGES_tg_ans_fr                  (GLOBAL.pages.table_subgoal_answer_frame_pages)
-#define GLOBAL_PAGES_tab_ent                    (GLOBAL.pages.table_entry_pages)
-#define GLOBAL_PAGES_sg_fr                      (GLOBAL.pages.subgoal_frame_pages)
-#define GLOBAL_PAGES_dep_fr                     (GLOBAL.pages.dependency_frame_pages)
-#define GLOBAL_PAGES_sg_node                    (GLOBAL.pages.subgoal_trie_node_pages)
-#define GLOBAL_PAGES_ans_node                   (GLOBAL.pages.answer_trie_node_pages)
-#define GLOBAL_PAGES_gt_node                    (GLOBAL.pages.global_trie_node_pages)
-#define GLOBAL_PAGES_sg_hash                    (GLOBAL.pages.subgoal_trie_hash_pages)
-#define GLOBAL_PAGES_ans_hash                   (GLOBAL.pages.answer_trie_hash_pages)
-#define GLOBAL_PAGES_gt_hash                    (GLOBAL.pages.global_trie_hash_pages)
-#define GLOBAL_PAGES_susp_fr                    (GLOBAL.pages.suspension_frame_pages)
-#define SCHEDULER_LOOP                          (GLOBAL.scheduler_loop)
-#define DELAYED_RELEASE_LOAD                    (GLOBAL.delayed_release_load)
-#define number_workers                          (GLOBAL.number_workers)
-#define worker_pid(worker)                      (GLOBAL.worker_pid[worker])
-#define GLOBAL_master_worker                    (GLOBAL.master_worker)
-#define GLOBAL_execution_time                   (GLOBAL.execution_time)
-#define GLOBAL_best_times(time)                 (GLOBAL.best_execution_times[time])
-#define GLOBAL_number_goals                     (GLOBAL.number_of_executed_goals)
-#define GLOBAL_performance_mode                 (GLOBAL.performance_mode)
+#define Yap_max_pages                        (Yap_optyap_data.pages.max_pages)
+#define Yap_pages_void                       (Yap_optyap_data.pages.void_pages)
+#define Yap_pages_or_fr                       (Yap_optyap_data.pages.or_frame_pages)
+#define Yap_pages_qg_sol_fr                   (Yap_optyap_data.pages.query_goal_solution_frame_pages)
+#define Yap_pages_qg_ans_fr                 (Yap_optyap_data.pages.query_goal_answer_frame_pages)
+#define Yap_pages_tg_sol_fr                  (Yap_optyap_data.pages.table_subgoal_solution_frame_pages)
+#define Yap_pages_tg_ans_fr                  (Yap_optyap_data.pages.table_subgoal_answer_frame_pages)
+#define Yap_pages_tab_ent                    (Yap_optyap_data.pages.table_entry_pages)
+#define Yap_pages_sg_fr                      (Yap_optyap_data.pages.subgoal_frame_pages)
+#define Yap_pages_dep_fr                     (Yap_optyap_data.pages.dependency_frame_pages)
+#define Yap_pages_sg_node                    (Yap_optyap_data.pages.subgoal_trie_node_pages)
+#define Yap_pages_ans_node                   (Yap_optyap_data.pages.answer_trie_node_pages)
+#define Yap_pages_gt_node                    (Yap_optyap_data.pages.global_trie_node_pages)
+#define Yap_pages_sg_hash                    (Yap_optyap_data.pages.subgoal_trie_hash_pages)
+#define Yap_pages_ans_hash                   (Yap_optyap_data.pages.answer_trie_hash_pages)
+#define Yap_pages_gt_hash                    (Yap_optyap_data.pages.global_trie_hash_pages)
+#define Yap_pages_susp_fr                    (Yap_optyap_data.pages.suspension_frame_pages)
+#define Yap_scheduler_loop                          (Yap_optyap_data.scheduler_loop)
+#define Yap_delayed_release_load                    (Yap_optyap_data.delayed_release_load)
+#define Yap_number_workers                          (Yap_optyap_data.number_workers)
+#define Yap_worker_pid(worker)                      (Yap_optyap_data.worker_pid[worker])
+#define Yap_master_worker                    (Yap_optyap_data.master_worker)
+#define Yap_execution_time                   (Yap_optyap_data.execution_time)
+#define Yap_best_times(time)                 (Yap_optyap_data.best_execution_times[time])
+#define Yap_number_goals                     (Yap_optyap_data.number_of_executed_goals)
+#define Yap_performance_mode                 (Yap_optyap_data.performance_mode)
 #if THREADS
-#define Get_GLOBAL_root_cp()	                offset_to_cptr(GLOBAL.root_choice_point_offset)
-#define Set_GLOBAL_root_cp(bptr)                (GLOBAL.root_choice_point_offset = cptr_to_offset(bptr))
+#define Get_Yap_root_cp()	                offset_to_cptr(Yap_optyap_data.root_choice_point_offset)
+#define Set_Yap_root_cp(bptr)                (Yap_optyap_data.root_choice_point_offset = cptr_to_offset(bptr))
 #else
-#define GLOBAL_root_cp                          (GLOBAL.root_choice_point)
-#define Get_GLOBAL_root_cp()                    (GLOBAL.root_choice_point)
-#define Set_GLOBAL_root_cp(bptr)                (GLOBAL.root_choice_point = (bptr))
+#define Yap_root_cp                          (Yap_optyap_data.root_choice_point)
+#define Get_Yap_root_cp()                    (Yap_optyap_data.root_choice_point)
+#define Set_Yap_root_cp(bptr)                (Yap_optyap_data.root_choice_point = (bptr))
 #endif
-#define GLOBAL_root_or_fr                       (GLOBAL.root_or_frame)
-#define GLOBAL_bm_present_workers               (GLOBAL.present_workers)
-#define GLOBAL_bm_idle_workers                  (GLOBAL.idle_workers)
-#define GLOBAL_bm_root_cp_workers               (GLOBAL.root_cp_workers)
-#define GLOBAL_bm_invisible_workers             (GLOBAL.invisible_workers)
-#define GLOBAL_bm_requestable_workers           (GLOBAL.requestable_workers)
-#define GLOBAL_bm_executing_workers             (GLOBAL.executing_workers)
-#define GLOBAL_bm_finished_workers              (GLOBAL.finished_workers)
-#define GLOBAL_bm_pruning_workers               (GLOBAL.pruning_workers)
-#define GLOBAL_LOCKS_bm_idle_workers            (GLOBAL.locks.bitmap_idle_workers)
-#define GLOBAL_LOCKS_bm_root_cp_workers         (GLOBAL.locks.bitmap_root_cp_workers)
-#define GLOBAL_LOCKS_bm_invisible_workers       (GLOBAL.locks.bitmap_invisible_workers)
-#define GLOBAL_LOCKS_bm_requestable_workers     (GLOBAL.locks.bitmap_requestable_workers)
-#define GLOBAL_LOCKS_bm_executing_workers       (GLOBAL.locks.bitmap_executing_workers)
-#define GLOBAL_LOCKS_bm_finished_workers        (GLOBAL.locks.bitmap_finished_workers)
-#define GLOBAL_LOCKS_bm_pruning_workers         (GLOBAL.locks.bitmap_pruning_workers)
-#define GLOBAL_LOCKS_who_locked_heap            (GLOBAL.locks.who_locked_heap)
-#define GLOBAL_LOCKS_heap_access                (GLOBAL.locks.heap_access)
-#define GLOBAL_LOCKS_alloc_block                (GLOBAL.locks.alloc_block)
-#define GLOBAL_branch(worker, depth)            (GLOBAL.branch[worker][depth])
-#define PARALLEL_EXECUTION_MODE                 (GLOBAL.parallel_execution_mode)
-#define GLOBAL_answers                          (GLOBAL.answers)
-#define GLOBAL_root_gt                          (GLOBAL.root_global_trie)
-#define GLOBAL_root_tab_ent                     (GLOBAL.root_table_entry)
-#define GLOBAL_first_sg_fr                      (GLOBAL.first_subgoal_frame)
-#define GLOBAL_last_sg_fr                       (GLOBAL.last_subgoal_frame)
-#define GLOBAL_check_sg_fr                      (GLOBAL.check_subgoal_frame)
-#define GLOBAL_root_dep_fr                      (GLOBAL.root_dependency_frame)
-#define GLOBAL_table_var_enumerator(index)      (GLOBAL.table_var_enumerator[index])
-#define GLOBAL_table_var_enumerator_addr(index) (GLOBAL.table_var_enumerator + (index))
-#define GLOBAL_table_lock(index)                (GLOBAL.table_lock[index])
-#define GLOBAL_timestamp                        (GLOBAL.timestamp)
+#define Yap_root_or_fr                       (Yap_optyap_data.root_or_frame)
+#define Yap_bm_present_workers               (Yap_optyap_data.present_workers)
+#define Yap_bm_idle_workers                  (Yap_optyap_data.idle_workers)
+#define Yap_bm_root_cp_workers               (Yap_optyap_data.root_cp_workers)
+#define Yap_bm_invisible_workers             (Yap_optyap_data.invisible_workers)
+#define Yap_bm_requestable_workers           (Yap_optyap_data.requestable_workers)
+#define Yap_bm_executing_workers             (Yap_optyap_data.executing_workers)
+#define Yap_bm_finished_workers              (Yap_optyap_data.finished_workers)
+#define Yap_bm_pruning_workers               (Yap_optyap_data.pruning_workers)
+#define Yap_locks_bm_idle_workers            (Yap_optyap_data.locks.bitmap_idle_workers)
+#define Yap_locks_bm_root_cp_workers         (Yap_optyap_data.locks.bitmap_root_cp_workers)
+#define Yap_locks_bm_invisible_workers       (Yap_optyap_data.locks.bitmap_invisible_workers)
+#define Yap_locks_bm_requestable_workers     (Yap_optyap_data.locks.bitmap_requestable_workers)
+#define Yap_locks_bm_executing_workers       (Yap_optyap_data.locks.bitmap_executing_workers)
+#define Yap_locks_bm_finished_workers        (Yap_optyap_data.locks.bitmap_finished_workers)
+#define Yap_locks_bm_pruning_workers         (Yap_optyap_data.locks.bitmap_pruning_workers)
+#define Yap_locks_who_locked_heap            (Yap_optyap_data.locks.who_locked_heap)
+#define Yap_locks_heap_access                (Yap_optyap_data.locks.heap_access)
+#define Yap_locks_alloc_block                (Yap_optyap_data.locks.alloc_block)
+#define Yap_branch(worker, depth)            (Yap_optyap_data.branch[worker][depth])
+#define Yap_parallel_execution_mode             (Yap_optyap_data.parallel_execution_mode)
+#define Yap_answers                          (Yap_optyap_data.answers)
+#define Yap_root_gt                          (Yap_optyap_data.root_global_trie)
+#define Yap_root_tab_ent                     (Yap_optyap_data.root_table_entry)
+#define Yap_first_sg_fr                      (Yap_optyap_data.first_subgoal_frame)
+#define Yap_last_sg_fr                       (Yap_optyap_data.last_subgoal_frame)
+#define Yap_check_sg_fr                      (Yap_optyap_data.check_subgoal_frame)
+#define Yap_root_dep_fr                      (Yap_optyap_data.root_dependency_frame)
+#define Yap_table_var_enumerator(index)      (Yap_optyap_data.table_var_enumerator[index])
+#define Yap_table_var_enumerator_addr(index) (Yap_optyap_data.table_var_enumerator + (index))
+#define Yap_table_lock(index)                (Yap_optyap_data.table_lock[index])
+#define Yap_timestamp                        (Yap_optyap_data.timestamp)
 
 
 
@@ -298,7 +298,7 @@ struct global_data{
 
 #ifdef YAPOR
 struct local_signals{
-#if defined(ENV_COPY) || defined(THREADS)
+#if defined(YAPOR_COPY) || defined(THREADS)
   lockvar lock;
   volatile enum {
     Q_idle = 0,
@@ -307,7 +307,7 @@ struct local_signals{
     local  = 3,
     P_idle = 4
   } P_fase, Q_fase;
-#endif /* ENV_COPY || THREADS */
+#endif /* YAPOR_COPY || THREADS */
   volatile enum {
     no_sharing   = 0, 
     sharing      = 1,
diff --git a/OPTYap/or.engine.c b/OPTYap/or.copy_engine.c
similarity index 97%
rename from OPTYap/or.engine.c
rename to OPTYap/or.copy_engine.c
index 1b73bb3bd..fb5045a8a 100644
--- a/OPTYap/or.engine.c
+++ b/OPTYap/or.copy_engine.c
@@ -16,7 +16,7 @@
 ** ------------------ */
 
 #include "Yap.h"
-#ifdef ENV_COPY
+#ifdef YAPOR_COPY
 #ifdef HAVE_STRING_H
 #include <string.h>
 #endif /* HAVE_STRING_H */
@@ -97,15 +97,15 @@ static void share_private_nodes(int worker_q);
 
 void make_root_choice_point(void) {
   if (worker_id == 0) {
-    LOCAL_top_cp = GLOBAL_root_cp = OrFr_node(GLOBAL_root_or_fr) = B;
+    LOCAL_top_cp = Yap_root_cp = OrFr_node(Yap_root_or_fr) = B;
   } else {
-    B = LOCAL_top_cp = GLOBAL_root_cp;
+    B = LOCAL_top_cp = Yap_root_cp;
     B->cp_tr = TR = ((choiceptr) (worker_offset(0) + (CELL)(B)))->cp_tr;
   }
   B->cp_h = H0;
   B->cp_ap = GETWORK;
-  B->cp_or_fr = GLOBAL_root_or_fr;
-  LOCAL_top_or_fr = GLOBAL_root_or_fr;
+  B->cp_or_fr = Yap_root_or_fr;
+  LOCAL_top_or_fr = Yap_root_or_fr;
   LOCAL_load = 0;
   Set_LOCAL_prune_request(NULL);
   BRANCH(worker_id, 0) = 0;
@@ -125,7 +125,7 @@ void free_root_choice_point(void) {
 #ifdef TABLING
   LOCAL_top_cp_on_stack =
 #endif /* TABLING */
-  LOCAL_top_cp = GLOBAL_root_cp = OrFr_node(GLOBAL_root_or_fr) = (choiceptr) Yap_LocalBase;
+  LOCAL_top_cp = Yap_root_cp = OrFr_node(Yap_root_or_fr) = (choiceptr) Yap_LocalBase;
   return;
 }
 
@@ -135,7 +135,7 @@ int p_share_work(void) {
 
   if (! BITMAP_member(OrFr_members(REMOTE_top_or_fr(worker_q)), worker_id) ||
       B == REMOTE_top_cp(worker_q) ||
-      (LOCAL_load <= DELAYED_RELEASE_LOAD && OrFr_nearest_livenode(LOCAL_top_or_fr) == NULL)) {
+      (LOCAL_load <= Yap_delayed_release_load  && OrFr_nearest_livenode(LOCAL_top_or_fr) == NULL)) {
     /* refuse sharing request */
     REMOTE_reply_signal(LOCAL_share_request) = no_sharing;
     LOCAL_share_request = MAX_WORKERS;
@@ -242,7 +242,7 @@ int q_share_work(int worker_p) {
 
   /* make sharing request */
   LOCK_WORKER(worker_p);
-  if (BITMAP_member(GLOBAL_bm_idle_workers, worker_p) || 
+  if (BITMAP_member(Yap_bm_idle_workers, worker_p) || 
       REMOTE_share_request(worker_p) != MAX_WORKERS) {
     /* worker p is idle or has another request */
     UNLOCK_WORKER(worker_p);
@@ -321,6 +321,7 @@ sync_with_p:
       if (IN_BETWEEN(Yap_TrailBase, aux_cell, Yap_TrailTop)) {
         /* avoid frozen segments */
         aux_tr = (tr_fr_ptr) aux_cell;
+      }
 #endif /* TABLING */
 #ifdef MULTI_ASSIGNMENT_VARIABLES
     } else if (IsApplTerm(aux_cell)) {
@@ -356,7 +357,6 @@ sync_with_p:
 }
 
 
-
 /* ------------------------- **
 **      Local functions      **
 ** ------------------------- */
@@ -523,7 +523,7 @@ void share_private_nodes(int worker_q) {
           next_node_on_branch = sharing_node;
         STACK_PUSH_UP(or_frame, stack);
         STACK_CHECK_EXPAND(stack, stack_limit);
-        STACK_PUSH(sharing_node, stack);
+        STACK_PUSH_UP(sharing_node, stack);
         STACK_CHECK_EXPAND(stack, stack_limit);
         sharing_node = consumer_cp;
         dep_frame = DepFr_next(dep_frame);
@@ -658,7 +658,7 @@ void share_private_nodes(int worker_q) {
 
 #ifdef DEBUG_OPTYAP
     { dep_fr_ptr aux_dep_fr = LOCAL_top_dep_fr;
-      while(aux_dep_fr != GLOBAL_root_dep_fr) {
+      while(aux_dep_fr != Yap_root_dep_fr) {
         choiceptr top_cp_on_branch;
         top_cp_on_branch = DepFr_cons_cp(aux_dep_fr);
         while (YOUNGER_CP(top_cp_on_branch, B)) {
@@ -698,4 +698,4 @@ void share_private_nodes(int worker_q) {
   REMOTE_load(worker_q) = LOCAL_load = 0;
   return;
 }
-#endif /* ENV_COPY */
+#endif /* YAPOR_COPY */
diff --git a/OPTYap/or.cowengine.c b/OPTYap/or.cow_engine.c
similarity index 99%
rename from OPTYap/or.cowengine.c
rename to OPTYap/or.cow_engine.c
index cd52ce7ca..e0c8ba5e8 100644
--- a/OPTYap/or.cowengine.c
+++ b/OPTYap/or.cow_engine.c
@@ -16,7 +16,7 @@
 ** ------------------ */
 
 #include "Yap.h"
-#ifdef ACOW
+#ifdef YAPOR_COW
 #include <sys/types.h>
 #include <unistd.h>
 #include <stdio.h>
@@ -230,4 +230,4 @@ void share_private_nodes(int worker_q) {
   REMOTE_load(worker_q) = LOCAL_load = 0;
   return;
 }
-#endif /* ACOW */
+#endif /* YAPOR_COW */
diff --git a/OPTYap/or.cut.c b/OPTYap/or.cut.c
index 0ac35532c..0b6088237 100644
--- a/OPTYap/or.cut.c
+++ b/OPTYap/or.cut.c
@@ -58,7 +58,7 @@ void prune_shared_branch(choiceptr prune_cp) {
     LOCK_OR_FRAME(prune_or_fr);
     members = OrFr_members(prune_or_fr);
     BITMAP_delete(members, worker_id);
-    for (i = 0; i < number_workers; i++) {
+    for (i = 0; i < Yap_number_workers; i++) {
       if (BITMAP_member(members, i) && ltt == BRANCH_LTT(i, depth)) {
         CUT_send_prune_request(i, prune_cp);
       }
@@ -139,7 +139,7 @@ void prune_shared_branch(choiceptr prune_cp) {
     LOCK_OR_FRAME(leftmost_or_fr);
     members = OrFr_members(leftmost_or_fr);
     BITMAP_delete(members, worker_id);
-    for (i = 0; i < number_workers; i++) {
+    for (i = 0; i < Yap_number_workers; i++) {
       if (BITMAP_member(members, i)) {
         if (ltt >= BRANCH_LTT(i, depth)) {
           CUT_send_prune_request(i, leftmost_cp->cp_b);
@@ -231,7 +231,7 @@ void prune_shared_branch(choiceptr prune_cp) {
           ltt = BRANCH_LTT(worker_id, depth);
           LOCK_OR_FRAME(leftmost_or_fr);
           BITMAP_difference(members, OrFr_members(leftmost_or_fr), members);
-          for (i = 0; i < number_workers; i++) {
+          for (i = 0; i < Yap_number_workers; i++) {
             if (BITMAP_member(members, i)) {
               if (ltt > BRANCH_LTT(i, depth)) {
                 CUT_send_prune_request(i, leftmost_cp->cp_b); 
diff --git a/OPTYap/or.insts.i b/OPTYap/or.insts.i
index e918e75cd..666a23763 100644
--- a/OPTYap/or.insts.i
+++ b/OPTYap/or.insts.i
@@ -17,22 +17,22 @@
 
   PBOp(getwork_first_time,e)
     /* wait for a new parallel goal */
-    while (BITMAP_same(GLOBAL_bm_present_workers, GLOBAL_bm_finished_workers));
+    while (BITMAP_same(Yap_bm_present_workers, Yap_bm_finished_workers));
     make_root_choice_point();  
     PUT_IN_EXECUTING(worker_id);
     /* wait until everyone else is executing! */
-    while (! BITMAP_same(GLOBAL_bm_present_workers, GLOBAL_bm_executing_workers));
+    while (! BITMAP_same(Yap_bm_present_workers, Yap_bm_executing_workers));
     SCHEDULER_GET_WORK();
   shared_end:
     PUT_IN_FINISHED(worker_id);
     /* wait until everyone else is finished! */
-    while (! BITMAP_same(GLOBAL_bm_present_workers, GLOBAL_bm_finished_workers));
+    while (! BITMAP_same(Yap_bm_present_workers, Yap_bm_finished_workers));
     PUT_OUT_EXECUTING(worker_id);
     if (worker_id == 0) {
       finish_yapor();
       free_root_choice_point();
       /* wait until no one is executing */
-      while (! BITMAP_empty(GLOBAL_bm_executing_workers));
+      while (! BITMAP_empty(Yap_bm_executing_workers));
       goto fail;
     } else {
       PREG = GETWORK_FIRST_TIME;
diff --git a/OPTYap/or.macros.h b/OPTYap/or.macros.h
index f6f099eb3..9ee749654 100644
--- a/OPTYap/or.macros.h
+++ b/OPTYap/or.macros.h
@@ -88,7 +88,7 @@ STD_PROTO(static inline qg_sol_fr_ptr CUT_prune_solution_frames, (qg_sol_fr_ptr,
 #define PUT_YAMOP_SEQ(INST)        (INST)->u.Otapl.or_arg |= YAMOP_SEQ_FLAG
 #define PUT_YAMOP_CUT(INST)        (INST)->u.Otapl.or_arg |= YAMOP_CUT_FLAG
 
-#define BRANCH(WORKER, DEPTH)      GLOBAL_branch(WORKER, DEPTH)
+#define BRANCH(WORKER, DEPTH)      Yap_branch(WORKER, DEPTH)
 #define BRANCH_LTT(WORKER, DEPTH)  (BRANCH(WORKER, DEPTH) & YAMOP_LTT_BITS)
 #define BRANCH_CUT(WORKER, DEPTH)  (BRANCH(WORKER, DEPTH) & YAMOP_CUT_FLAG)
 
@@ -135,7 +135,7 @@ STD_PROTO(static inline qg_sol_fr_ptr CUT_prune_solution_frames, (qg_sol_fr_ptr,
           SCHEDULER_GET_WORK();       \
         }
 
-#if defined(ENV_COPY) || defined(SBA) || defined(THREADS)
+#if defined(YAPOR_COPY) || defined(YAPOR_SBA) || defined(THREADS)
 #define SCH_check_share_request()     \
         if (SCH_any_share_request) {  \
 	  ASP = YENV;                 \
@@ -143,13 +143,13 @@ STD_PROTO(static inline qg_sol_fr_ptr CUT_prune_solution_frames, (qg_sol_fr_ptr,
           p_share_work();             \
 	  setregs();                  \
         }
-#else /* ACOW */
+#else /* YAPOR_COW */
 #define SCH_check_share_request()     \
         if (SCH_any_share_request) {  \
           if (! p_share_work())       \
             goto shared_fail;         \
         }
-#endif /* ENV_COPY || SBA || ACOW */
+#endif /* YAPOR_COPY || YAPOR_SBA || YAPOR_COW */
 
 #define SCH_check_requests()          \
         SCH_check_prune_request();    \
@@ -175,7 +175,7 @@ STD_PROTO(static inline qg_sol_fr_ptr CUT_prune_solution_frames, (qg_sol_fr_ptr,
 	}
 
 #define CUT_wait_leftmost()                                           \
-        if (PARALLEL_EXECUTION_MODE) {                                \
+        if (Yap_parallel_execution_mode) {                                \
            /* parallel execution mode --> wait until leftmost */      \
            int i, loop, depth, ltt;                                   \
            bitmap members;                                            \
@@ -189,13 +189,13 @@ STD_PROTO(static inline qg_sol_fr_ptr CUT_prune_solution_frames, (qg_sol_fr_ptr,
                SCH_check_requests();                                  \
                BITMAP_copy(members, OrFr_members(leftmost_or_fr));    \
                BITMAP_delete(members, worker_id);                     \
-               for (i = 0; i < number_workers; i++) {                 \
+               for (i = 0; i < Yap_number_workers; i++) {                 \
                  /*  not leftmost in current frame if there is a  */  \
 	         /* worker in a left branch and it is not idle or */  \
                  /*     if it is idle it is in a younger node     */  \
                  if (BITMAP_member(members, i) &&                     \
                      BRANCH_LTT(i, depth) > ltt &&                    \
-                     (! BITMAP_member(GLOBAL_bm_idle_workers, i) ||   \
+                     (! BITMAP_member(Yap_bm_idle_workers, i) ||   \
                       leftmost_or_fr != REMOTE_top_or_fr(i))) {       \
                    loop = TRUE;                                       \
                    break;                                             \
@@ -203,7 +203,7 @@ STD_PROTO(static inline qg_sol_fr_ptr CUT_prune_solution_frames, (qg_sol_fr_ptr,
                }                                                      \
              } while (loop);                                          \
              leftmost_or_fr = OrFr_nearest_leftnode(leftmost_or_fr);  \
-           } while (leftmost_or_fr != GLOBAL_root_or_fr);             \
+           } while (leftmost_or_fr != Yap_root_or_fr);             \
          }
 
 
@@ -214,27 +214,27 @@ STD_PROTO(static inline qg_sol_fr_ptr CUT_prune_solution_frames, (qg_sol_fr_ptr,
 
 static inline 
 void PUT_IN_EXECUTING(int w) {
-  LOCK(GLOBAL_LOCKS_bm_executing_workers);
-  BITMAP_insert(GLOBAL_bm_executing_workers, w);
-  UNLOCK(GLOBAL_LOCKS_bm_executing_workers);
+  LOCK(Yap_locks_bm_executing_workers);
+  BITMAP_insert(Yap_bm_executing_workers, w);
+  UNLOCK(Yap_locks_bm_executing_workers);
   return;
 }
 
 
 static inline 
 void PUT_OUT_EXECUTING(int w) {
-  LOCK(GLOBAL_LOCKS_bm_executing_workers);
-  BITMAP_delete(GLOBAL_bm_executing_workers, w);
-  UNLOCK(GLOBAL_LOCKS_bm_executing_workers);
+  LOCK(Yap_locks_bm_executing_workers);
+  BITMAP_delete(Yap_bm_executing_workers, w);
+  UNLOCK(Yap_locks_bm_executing_workers);
   return;
 }
 
 
 static inline 
 void PUT_IN_FINISHED(int w) {
-  LOCK(GLOBAL_LOCKS_bm_finished_workers);
-  BITMAP_insert(GLOBAL_bm_finished_workers, w);
-  UNLOCK(GLOBAL_LOCKS_bm_finished_workers);
+  LOCK(Yap_locks_bm_finished_workers);
+  BITMAP_insert(Yap_bm_finished_workers, w);
+  UNLOCK(Yap_locks_bm_finished_workers);
   return;
 }
 
@@ -242,18 +242,18 @@ void PUT_IN_FINISHED(int w) {
 #ifdef TABLING_INNER_CUTS
 static inline 
 void PUT_IN_PRUNING(int w) {
-  LOCK(GLOBAL_LOCKS_bm_pruning_workers);
-  BITMAP_insert(GLOBAL_bm_pruning_workers, w);
-  UNLOCK(GLOBAL_LOCKS_bm_pruning_workers);
+  LOCK(Yap_locks_bm_pruning_workers);
+  BITMAP_insert(Yap_bm_pruning_workers, w);
+  UNLOCK(Yap_locks_bm_pruning_workers);
   return;
 }
 
 
 static inline 
 void PUT_OUT_PRUNING(int w) {
-  LOCK(GLOBAL_LOCKS_bm_pruning_workers);
-  BITMAP_delete(GLOBAL_bm_pruning_workers, w);
-  UNLOCK(GLOBAL_LOCKS_bm_pruning_workers);
+  LOCK(Yap_locks_bm_pruning_workers);
+  BITMAP_delete(Yap_bm_pruning_workers, w);
+  UNLOCK(Yap_locks_bm_pruning_workers);
   return;
 }
 #endif /* TABLING_INNER_CUTS */
@@ -266,18 +266,18 @@ void PUT_OUT_PRUNING(int w) {
 
 static inline 
 void PUT_IN_REQUESTABLE(int p) {
-  LOCK(GLOBAL_LOCKS_bm_requestable_workers);
-  BITMAP_insert(GLOBAL_bm_requestable_workers, p);
-  UNLOCK(GLOBAL_LOCKS_bm_requestable_workers);
+  LOCK(Yap_locks_bm_requestable_workers);
+  BITMAP_insert(Yap_bm_requestable_workers, p);
+  UNLOCK(Yap_locks_bm_requestable_workers);
   return;
 }
 
 
 static inline 
 void PUT_OUT_REQUESTABLE(int p) {
-  LOCK(GLOBAL_LOCKS_bm_requestable_workers);
-  BITMAP_delete(GLOBAL_bm_requestable_workers, p);
-  UNLOCK(GLOBAL_LOCKS_bm_requestable_workers);
+  LOCK(Yap_locks_bm_requestable_workers);
+  BITMAP_delete(Yap_bm_requestable_workers, p);
+  UNLOCK(Yap_locks_bm_requestable_workers);
   return;
 }
 
@@ -379,7 +379,7 @@ int CUT_last_worker_left_pending_prune(or_fr_ptr or_frame) {
   ltt = OrFr_pend_prune_ltt(or_frame);
   members = OrFr_members(or_frame);
   BITMAP_delete(members, worker_id);
-  for (i = 0; i < number_workers; i++) {
+  for (i = 0; i < Yap_number_workers; i++) {
     if (BITMAP_member(members, i) && BRANCH_LTT(i, depth) > ltt)
       return FALSE;
   }
@@ -402,7 +402,7 @@ or_fr_ptr CUT_leftmost_or_frame(void) {
     ltt = BRANCH_LTT(worker_id, depth);
     BITMAP_difference(members, OrFr_members(leftmost_or_fr), members);
     if (members)
-      for (i = 0; i < number_workers; i++)
+      for (i = 0; i < Yap_number_workers; i++)
         if (BITMAP_member(members, i) && BRANCH_LTT(i, depth) > ltt)
           goto update_nearest_leftnode_data;
     BITMAP_copy(members, OrFr_members(leftmost_or_fr));
@@ -436,12 +436,12 @@ or_fr_ptr CUT_leftmost_until(or_fr_ptr start_or_fr, int until_depth) {
   leftmost_or_fr = OrFr_nearest_leftnode(start_or_fr);
   depth = OrFr_depth(leftmost_or_fr);
   if (depth > until_depth) {
-    BITMAP_copy(prune_members, GLOBAL_bm_pruning_workers);
+    BITMAP_copy(prune_members, Yap_bm_pruning_workers);
     BITMAP_delete(prune_members, worker_id);
     ltt = BRANCH_LTT(worker_id, depth);
     BITMAP_intersection(members, prune_members, OrFr_members(leftmost_or_fr));
     if (members) {
-      for (i = 0; i < number_workers; i++) {
+      for (i = 0; i < Yap_number_workers; i++) {
         if (BITMAP_member(members, i) && 
             BRANCH_LTT(i, depth) > ltt &&
             EQUAL_OR_YOUNGER_CP(GetOrFr_node(leftmost_or_fr), REMOTE_pruning_scope(i)))
@@ -456,7 +456,7 @@ or_fr_ptr CUT_leftmost_until(or_fr_ptr start_or_fr, int until_depth) {
       ltt = BRANCH_LTT(worker_id, depth);
       BITMAP_intersection(members, prune_members, OrFr_members(leftmost_or_fr));
       if (members) {
-        for (i = 0; i < number_workers; i++) {
+        for (i = 0; i < Yap_number_workers; i++) {
           if (BITMAP_member(members, i) &&
               BRANCH_LTT(i, depth) > ltt &&
               EQUAL_OR_YOUNGER_CP(GetOrFr_node(leftmost_or_fr), REMOTE_pruning_scope(i))) {
diff --git a/OPTYap/or.sbaamiops.h b/OPTYap/or.sba_amiops.h
similarity index 100%
rename from OPTYap/or.sbaamiops.h
rename to OPTYap/or.sba_amiops.h
diff --git a/OPTYap/or.sbaengine.c b/OPTYap/or.sba_engine.c
similarity index 99%
rename from OPTYap/or.sbaengine.c
rename to OPTYap/or.sba_engine.c
index bb00a7d30..84f27b05f 100644
--- a/OPTYap/or.sbaengine.c
+++ b/OPTYap/or.sba_engine.c
@@ -16,7 +16,7 @@
 ** ------------------ */
 
 #include "Yap.h"
-#ifdef SBA
+#ifdef YAPOR_SBA
 #include <stdio.h>
 #include "Yatom.h"
 #include "YapHeap.h"
diff --git a/OPTYap/or.sbaunify.h b/OPTYap/or.sba_unify.h
similarity index 100%
rename from OPTYap/or.sbaunify.h
rename to OPTYap/or.sba_unify.h
diff --git a/OPTYap/or.scheduler.c b/OPTYap/or.scheduler.c
index 1cd3bc160..8931bb8e6 100644
--- a/OPTYap/or.scheduler.c
+++ b/OPTYap/or.scheduler.c
@@ -65,36 +65,36 @@ void PUT_NO_WORK_IN_UPPER_NODES(void) {
 
 static inline
 void PUT_IDLE(int worker_num) {
-  LOCK(GLOBAL_LOCKS_bm_idle_workers);
-  BITMAP_insert(GLOBAL_bm_idle_workers, worker_num);
-  UNLOCK(GLOBAL_LOCKS_bm_idle_workers);
+  LOCK(Yap_locks_bm_idle_workers);
+  BITMAP_insert(Yap_bm_idle_workers, worker_num);
+  UNLOCK(Yap_locks_bm_idle_workers);
   return;
 }
 
 
 static inline
 void PUT_BUSY(int worker_num) {
-  LOCK(GLOBAL_LOCKS_bm_idle_workers);
-  BITMAP_delete(GLOBAL_bm_idle_workers, worker_num);
-  UNLOCK(GLOBAL_LOCKS_bm_idle_workers);
+  LOCK(Yap_locks_bm_idle_workers);
+  BITMAP_delete(Yap_bm_idle_workers, worker_num);
+  UNLOCK(Yap_locks_bm_idle_workers);
   return;
 }
 
 
 static inline
 void PUT_IN_ROOT_NODE(int worker_num) {
-  LOCK(GLOBAL_LOCKS_bm_root_cp_workers);
-  BITMAP_insert(GLOBAL_bm_root_cp_workers, worker_num);
-  UNLOCK(GLOBAL_LOCKS_bm_root_cp_workers);
+  LOCK(Yap_locks_bm_root_cp_workers);
+  BITMAP_insert(Yap_bm_root_cp_workers, worker_num);
+  UNLOCK(Yap_locks_bm_root_cp_workers);
   return;
 }
 
 
 static inline
 void PUT_OUT_ROOT_NODE(int worker_num) {
-  LOCK(GLOBAL_LOCKS_bm_root_cp_workers);
-  BITMAP_delete(GLOBAL_bm_root_cp_workers, worker_num);
-  UNLOCK(GLOBAL_LOCKS_bm_root_cp_workers);
+  LOCK(Yap_locks_bm_root_cp_workers);
+  BITMAP_delete(Yap_bm_root_cp_workers, worker_num);
+  UNLOCK(Yap_locks_bm_root_cp_workers);
   return;
 }
 
@@ -215,21 +215,21 @@ int get_work(void) {
   SCH_refuse_share_request_if_any();
   
   counter = 0;
-  BITMAP_difference(stable_busy, OrFr_members(LOCAL_top_or_fr), GLOBAL_bm_idle_workers);
+  BITMAP_difference(stable_busy, OrFr_members(LOCAL_top_or_fr), Yap_bm_idle_workers);
   while (1) {
-    while (BITMAP_subset(GLOBAL_bm_idle_workers, OrFr_members(LOCAL_top_or_fr)) &&
-           Get_LOCAL_top_cp() != Get_GLOBAL_root_cp()) {
+    while (BITMAP_subset(Yap_bm_idle_workers, OrFr_members(LOCAL_top_or_fr)) &&
+           Get_LOCAL_top_cp() != Get_Yap_root_cp()) {
       /* no busy workers here and below */
       if (! move_up_one_node(NULL)) {
         PUT_BUSY(worker_id);
         return TRUE;
       }
     }
-    if (Get_LOCAL_top_cp() == Get_GLOBAL_root_cp()) {
-      if (! BITMAP_member(GLOBAL_bm_root_cp_workers, worker_id))
+    if (Get_LOCAL_top_cp() == Get_Yap_root_cp()) {
+      if (! BITMAP_member(Yap_bm_root_cp_workers, worker_id))
         PUT_IN_ROOT_NODE(worker_id);
-      if (BITMAP_same(GLOBAL_bm_idle_workers, GLOBAL_bm_root_cp_workers) &&
-          BITMAP_same(GLOBAL_bm_idle_workers, GLOBAL_bm_present_workers)) {
+      if (BITMAP_same(Yap_bm_idle_workers, Yap_bm_root_cp_workers) &&
+          BITMAP_same(Yap_bm_idle_workers, Yap_bm_present_workers)) {
         /* All workers are idle in root choicepoint. Execution 
            must finish as there is no available computation. */
         return FALSE;
@@ -247,15 +247,15 @@ int get_work(void) {
       PUT_BUSY(worker_id);
       return TRUE;
     }
-    if (++counter == SCHEDULER_LOOP) {
+    if (++counter == Yap_scheduler_loop) {
       if (search_for_hidden_shared_work(stable_busy)) {
         PUT_BUSY(worker_id);
         return TRUE;
       }
       counter = 0;
-      BITMAP_difference(stable_busy, OrFr_members(LOCAL_top_or_fr), GLOBAL_bm_idle_workers);
+      BITMAP_difference(stable_busy, OrFr_members(LOCAL_top_or_fr), Yap_bm_idle_workers);
     } else {
-      BITMAP_minus(stable_busy, GLOBAL_bm_idle_workers);
+      BITMAP_minus(stable_busy, Yap_bm_idle_workers);
     }
   }
 }
@@ -347,7 +347,7 @@ int move_up_one_node(or_fr_ptr nearest_livenode) {
   if (OrFr_suspensions(LOCAL_top_or_fr)) {
     susp_fr_ptr resume_fr;
 #ifdef TIMESTAMP_CHECK
-    resume_fr = suspension_frame_to_resume(LOCAL_top_or_fr, ++GLOBAL_timestamp);
+    resume_fr = suspension_frame_to_resume(LOCAL_top_or_fr, ++Yap_timestamp);
 #else
     resume_fr = suspension_frame_to_resume(LOCAL_top_or_fr);
 #endif /* TIMESTAMP_CHECK */
@@ -528,18 +528,18 @@ int get_work_below(void){
   bitmap busy_below, idle_below;
 
   worker_p = -1;
-  big_load = DELAYED_RELEASE_LOAD;
-  BITMAP_difference(busy_below, OrFr_members(LOCAL_top_or_fr), GLOBAL_bm_idle_workers);
+  big_load = Yap_delayed_release_load ;
+  BITMAP_difference(busy_below, OrFr_members(LOCAL_top_or_fr), Yap_bm_idle_workers);
   BITMAP_difference(idle_below, OrFr_members(LOCAL_top_or_fr), busy_below);
   BITMAP_delete(idle_below, worker_id);
-  for (i = 0; i < number_workers; i++) {
+  for (i = 0; i < Yap_number_workers; i++) {
     if (BITMAP_member(idle_below ,i) && YOUNGER_CP(REMOTE_top_cp(i), Get_LOCAL_top_cp()))
       BITMAP_minus(busy_below, OrFr_members(REMOTE_top_or_fr(i)));
   }
   if (BITMAP_empty(busy_below))
     return FALSE;
   /* choose the worker with highest load */
-  for (i = 0 ; i < number_workers; i++) {
+  for (i = 0 ; i < Yap_number_workers; i++) {
     if (BITMAP_member(busy_below ,i) && REMOTE_load(i) > big_load) {
       worker_p = i;
       big_load = REMOTE_load(i);
@@ -558,14 +558,14 @@ int get_work_above(void){
   bitmap visible_busy_above, visible_idle_above;
 
   worker_p = -1; 
-  big_load = DELAYED_RELEASE_LOAD;
-  BITMAP_difference(visible_busy_above, GLOBAL_bm_present_workers, OrFr_members(LOCAL_top_or_fr));
-  BITMAP_minus(visible_busy_above, GLOBAL_bm_invisible_workers);
+  big_load = Yap_delayed_release_load ;
+  BITMAP_difference(visible_busy_above, Yap_bm_present_workers, OrFr_members(LOCAL_top_or_fr));
+  BITMAP_minus(visible_busy_above, Yap_bm_invisible_workers);
   BITMAP_copy(visible_idle_above, visible_busy_above); 
-  BITMAP_minus(visible_busy_above, GLOBAL_bm_idle_workers);
-  BITMAP_and(visible_idle_above, GLOBAL_bm_idle_workers);
+  BITMAP_minus(visible_busy_above, Yap_bm_idle_workers);
+  BITMAP_and(visible_idle_above, Yap_bm_idle_workers);
   BITMAP_insert(visible_busy_above, worker_id);
-  for (i = 0 ; i < number_workers; i++) {
+  for (i = 0 ; i < Yap_number_workers; i++) {
     if (BITMAP_member(visible_idle_above, i))
       BITMAP_minus(visible_busy_above, OrFr_members(REMOTE_top_or_fr(i)));
   }
@@ -573,7 +573,7 @@ int get_work_above(void){
     return FALSE;
   BITMAP_delete(visible_busy_above, worker_id);
   /* choose the worker with higher load */
-  for (i = 0; i < number_workers; i++) {
+  for (i = 0; i < Yap_number_workers; i++) {
     if (BITMAP_member(visible_busy_above ,i) && REMOTE_load(i) > big_load) {
       worker_p = i;
       big_load = REMOTE_load(i);
@@ -582,14 +582,14 @@ int get_work_above(void){
   if (worker_p == -1)
     return FALSE;
   /* put workers invisibles */
-  LOCK(GLOBAL_LOCKS_bm_invisible_workers);
-  if (BITMAP_member(GLOBAL_bm_invisible_workers, worker_p)) {
-    UNLOCK(GLOBAL_LOCKS_bm_invisible_workers);
+  LOCK(Yap_locks_bm_invisible_workers);
+  if (BITMAP_member(Yap_bm_invisible_workers, worker_p)) {
+    UNLOCK(Yap_locks_bm_invisible_workers);
     return FALSE;
   }
-  BITMAP_insert(GLOBAL_bm_invisible_workers, worker_id);
-  BITMAP_insert(GLOBAL_bm_invisible_workers, worker_p);
-  UNLOCK(GLOBAL_LOCKS_bm_invisible_workers);
+  BITMAP_insert(Yap_bm_invisible_workers, worker_id);
+  BITMAP_insert(Yap_bm_invisible_workers, worker_p);
+  UNLOCK(Yap_locks_bm_invisible_workers);
   /* move up to cp with worker_p */
   do {
     if (! move_up_one_node(NULL)) {
@@ -597,10 +597,10 @@ int get_work_above(void){
     }
   } while (! BITMAP_member(OrFr_members(LOCAL_top_or_fr), worker_p));
   /* put workers visibles */
-  LOCK(GLOBAL_LOCKS_bm_invisible_workers);
-  BITMAP_delete(GLOBAL_bm_invisible_workers, worker_id);
-  BITMAP_delete(GLOBAL_bm_invisible_workers, worker_p);
-  UNLOCK(GLOBAL_LOCKS_bm_invisible_workers);
+  LOCK(Yap_locks_bm_invisible_workers);
+  BITMAP_delete(Yap_bm_invisible_workers, worker_id);
+  BITMAP_delete(Yap_bm_invisible_workers, worker_p);
+  UNLOCK(Yap_locks_bm_invisible_workers);
   return (q_share_work(worker_p));
 }
 
@@ -610,11 +610,11 @@ int find_a_better_position(void){
   CACHE_REGS
   int i;
   bitmap busy_above, idle_above;
-  BITMAP_difference(busy_above, GLOBAL_bm_present_workers, OrFr_members(LOCAL_top_or_fr));
+  BITMAP_difference(busy_above, Yap_bm_present_workers, OrFr_members(LOCAL_top_or_fr));
   BITMAP_copy(idle_above, busy_above); 
-  BITMAP_minus(busy_above, GLOBAL_bm_idle_workers);
-  BITMAP_and(idle_above, GLOBAL_bm_idle_workers);
-  for (i = 0; i < number_workers; i++) {
+  BITMAP_minus(busy_above, Yap_bm_idle_workers);
+  BITMAP_and(idle_above, Yap_bm_idle_workers);
+  for (i = 0; i < Yap_number_workers; i++) {
     if (BITMAP_member(idle_above, i)) {
       if (BITMAP_empty(busy_above)) 
         break;
@@ -640,17 +640,17 @@ int search_for_hidden_shared_work(bitmap stable_busy){
   CACHE_REGS
   int i;
   bitmap invisible_work, idle_below;
-  BITMAP_intersection(invisible_work, stable_busy, GLOBAL_bm_requestable_workers);
-  BITMAP_intersection(idle_below, OrFr_members(LOCAL_top_or_fr), GLOBAL_bm_idle_workers);
+  BITMAP_intersection(invisible_work, stable_busy, Yap_bm_requestable_workers);
+  BITMAP_intersection(idle_below, OrFr_members(LOCAL_top_or_fr), Yap_bm_idle_workers);
   BITMAP_delete(idle_below, worker_id);
-  for (i = 0; i < number_workers; i++) {
+  for (i = 0; i < Yap_number_workers; i++) {
     if (BITMAP_member(idle_below ,i) && YOUNGER_CP(REMOTE_top_cp(i), Get_LOCAL_top_cp()))
       BITMAP_minus(invisible_work, OrFr_members(REMOTE_top_or_fr(i)));
   }
   if (BITMAP_empty(invisible_work))
     return FALSE;
   /* choose the first available worker */
-  for (i = 0; i < number_workers; i++ ) {
+  for (i = 0; i < Yap_number_workers; i++ ) {
     if (BITMAP_member(invisible_work ,i))
       break;
   }
diff --git a/OPTYap/or.threadengine.c b/OPTYap/or.thread_engine.c
similarity index 99%
rename from OPTYap/or.threadengine.c
rename to OPTYap/or.thread_engine.c
index 51b88a425..71f333cb0 100644
--- a/OPTYap/or.threadengine.c
+++ b/OPTYap/or.thread_engine.c
@@ -46,11 +46,6 @@
 static void share_private_nodes(int worker_q);
 
 
-
-/* ---------------------- **
-**      Local macros      **
-** ---------------------- */
-
 /* -------------------------- **
 **      Global functions      **
 ** -------------------------- */
@@ -544,4 +539,4 @@ void share_private_nodes(int worker_q) {
   REMOTE_load(worker_q) = LOCAL_load = 0;
   return;
 }
-#endif /* ENV_COPY */
+#endif /* YAPOR_COPY */
diff --git a/OPTYap/tab.insts.i b/OPTYap/tab.insts.i
index 2bc86619d..2f2226309 100644
--- a/OPTYap/tab.insts.i
+++ b/OPTYap/tab.insts.i
@@ -442,7 +442,7 @@
       find_leader_node(leader_cp, leader_dep_on_stack);
       store_consumer_node(tab_ent, sg_fr, leader_cp, leader_dep_on_stack);
 #ifdef DEBUG_OPTYAP
-      if (PARALLEL_EXECUTION_MODE) {
+      if (Yap_parallel_execution_mode) {
 	choiceptr aux_cp;
 	aux_cp = B;
 	while (YOUNGER_CP(aux_cp, Get_LOCAL_top_cp_on_stack()))
@@ -553,7 +553,7 @@
       find_leader_node(leader_cp, leader_dep_on_stack);
       store_consumer_node(tab_ent, sg_fr, leader_cp, leader_dep_on_stack);
 #ifdef DEBUG_OPTYAP
-      if (PARALLEL_EXECUTION_MODE) {
+      if (Yap_parallel_execution_mode) {
 	choiceptr aux_cp;
 	aux_cp = B;
 	while (YOUNGER_CP(aux_cp, Get_LOCAL_top_cp_on_stack()))
@@ -664,7 +664,7 @@
       find_leader_node(leader_cp, leader_dep_on_stack);
       store_consumer_node(tab_ent, sg_fr, leader_cp, leader_dep_on_stack);
 #ifdef DEBUG_OPTYAP
-      if (PARALLEL_EXECUTION_MODE) {
+      if (Yap_parallel_execution_mode) {
 	choiceptr aux_cp;
 	aux_cp = B;
 	while (YOUNGER_CP(aux_cp, Get_LOCAL_top_cp_on_stack()))
@@ -878,7 +878,7 @@
       /* new answer */
 #ifdef TABLING_INNER_CUTS
       /* check for potencial prunings */
-      if (! BITMAP_empty(GLOBAL_bm_pruning_workers)) {
+      if (! BITMAP_empty(Yap_bm_pruning_workers)) {
         int until_depth, depth;
 
         until_depth = OrFr_depth(SgFr_gen_top_or_fr(sg_fr));
@@ -888,7 +888,7 @@
           bitmap prune_members, members;
           or_fr_ptr leftmost_or_fr, or_fr, nearest_or_fr;
 
-          BITMAP_copy(prune_members, GLOBAL_bm_pruning_workers);
+          BITMAP_copy(prune_members, Yap_bm_pruning_workers);
           BITMAP_delete(prune_members, worker_id);
           ltt = BRANCH_LTT(worker_id, depth);
           BITMAP_intersection(members, prune_members, OrFr_members(LOCAL_top_or_fr));
@@ -1213,7 +1213,7 @@
           }
 #endif /* YAPOR */
 #ifdef DEBUG_OPTYAP
-	  if (PARALLEL_EXECUTION_MODE) {
+	  if (Yap_parallel_execution_mode) {
 	    choiceptr aux_cp;
 	    OPTYAP_ERROR_CHECKING(completion, YOUNGER_CP(Get_LOCAL_top_cp(), Get_LOCAL_top_cp_on_stack()));
 	    aux_cp = chain_cp;
@@ -1284,7 +1284,7 @@
       }
 #endif /* YAPOR */
 #ifdef DEBUG_OPTYAP
-      if (PARALLEL_EXECUTION_MODE) {
+      if (Yap_parallel_execution_mode) {
 	choiceptr aux_cp;
 	OPTYAP_ERROR_CHECKING(completion, YOUNGER_CP(Get_LOCAL_top_cp(), Get_LOCAL_top_cp_on_stack()));
 	aux_cp = chain_cp;
@@ -1381,7 +1381,7 @@
 
     if (SCH_top_shared_cp(B)) {
 #ifdef TIMESTAMP_CHECK
-      timestamp = ++GLOBAL_timestamp;
+      timestamp = ++Yap_timestamp;
 #endif /* TIMESTAMP_CHECK */
       entry_owners = OrFr_owners(LOCAL_top_or_fr);
     }
@@ -1409,7 +1409,7 @@
         UNLOCK(DepFr_lock(dep_fr));
 
 #ifdef DEBUG_OPTYAP
-        if (PARALLEL_EXECUTION_MODE) {
+        if (Yap_parallel_execution_mode) {
 	  choiceptr aux_cp;
 	  OPTYAP_ERROR_CHECKING(completion, Get_LOCAL_top_cp(), Get_LOCAL_top_cp_on_stack());
 	  aux_cp = DepFr_cons_cp(dep_fr);
@@ -1434,7 +1434,7 @@
         }
 #endif /* YAPOR */
 #ifdef DEBUG_OPTYAP
-        if (PARALLEL_EXECUTION_MODE) {
+        if (Yap_parallel_execution_mode) {
 	  choiceptr aux_cp;
 	  OPTYAP_ERROR_CHECKING(completion, YOUNGER_CP(Get_LOCAL_top_cp(), Get_LOCAL_top_cp_on_stack()));
 	  aux_cp = DepFr_cons_cp(dep_fr);
diff --git a/OPTYap/tab.macros.h b/OPTYap/tab.macros.h
index 5b3f86535..d13ad9602 100644
--- a/OPTYap/tab.macros.h
+++ b/OPTYap/tab.macros.h
@@ -111,10 +111,10 @@ static inline tg_sol_fr_ptr CUT_prune_tg_solution_frames(tg_sol_fr_ptr, int);
 #define MakeTableVarTerm(INDEX)    ((INDEX) << NumberOfLowTagBits)
 #define VarIndexOfTableTerm(TERM)  (((unsigned int) (TERM)) >> NumberOfLowTagBits)
 #define VarIndexOfTerm(TERM)                                                     \
-        ((((CELL) (TERM)) - GLOBAL_table_var_enumerator(0)) / sizeof(CELL))
+        ((((CELL) (TERM)) - Yap_table_var_enumerator(0)) / sizeof(CELL))
 #define IsTableVarTerm(TERM)                                                     \
-        ((CELL) (TERM)) >= GLOBAL_table_var_enumerator(0) &&		 	 \
-        ((CELL) (TERM)) <= GLOBAL_table_var_enumerator(MAX_TABLE_VARS - 1)
+        ((CELL) (TERM)) >= Yap_table_var_enumerator(0) &&		 	 \
+        ((CELL) (TERM)) <= Yap_table_var_enumerator(MAX_TABLE_VARS - 1)
 #ifdef TRIE_COMPACT_PAIRS
 #define PairTermMark        NULL
 #define CompactPairInit     AbsPair((Term *) 0)
@@ -154,8 +154,8 @@ static inline tg_sol_fr_ptr CUT_prune_tg_solution_frames(tg_sol_fr_ptr, int);
 #define IS_GLOBAL_TRIE_HASH(NODE)   (TrNode_entry(NODE) == GLOBAL_TRIE_HASH_MARK)
 
 #define HASH_TABLE_LOCK(NODE)  ((((unsigned long int) (NODE)) >> 5) & (TABLE_LOCK_BUCKETS - 1))
-#define LOCK_TABLE(NODE)         LOCK(GLOBAL_table_lock(HASH_TABLE_LOCK(NODE)))
-#define UNLOCK_TABLE(NODE)     UNLOCK(GLOBAL_table_lock(HASH_TABLE_LOCK(NODE)))
+#define LOCK_TABLE(NODE)         LOCK(Yap_table_lock(HASH_TABLE_LOCK(NODE)))
+#define UNLOCK_TABLE(NODE)     UNLOCK(Yap_table_lock(HASH_TABLE_LOCK(NODE)))
 
 #define STACK_PUSH_UP(ITEM, STACK)                  *--(STACK) = (CELL)(ITEM)
 #define STACK_POP_UP(STACK)                         *--(STACK)
@@ -290,8 +290,8 @@ static inline tg_sol_fr_ptr CUT_prune_tg_solution_frames(tg_sol_fr_ptr, int);
             SetMode_GlobalTrie(TabEnt_mode(TAB_ENT));            \
           TabEnt_subgoal_trie(TAB_ENT) = sg_node;                \
           TabEnt_hash_chain(TAB_ENT) = NULL;                     \
-          TabEnt_next(TAB_ENT) = GLOBAL_root_tab_ent;            \
-          GLOBAL_root_tab_ent = TAB_ENT;                         \
+          TabEnt_next(TAB_ENT) = Yap_root_tab_ent;            \
+          Yap_root_tab_ent = TAB_ENT;                         \
         }
 
 #define new_subgoal_frame(SG_FR, CODE)                             \
@@ -394,26 +394,26 @@ static inline tg_sol_fr_ptr CUT_prune_tg_solution_frames(tg_sol_fr_ptr, int);
 
 #ifdef LIMIT_TABLING
 #define insert_into_global_sg_fr_list(SG_FR)                                 \
-        SgFr_previous(SG_FR) = GLOBAL_last_sg_fr;                            \
+        SgFr_previous(SG_FR) = Yap_last_sg_fr;                            \
         SgFr_next(SG_FR) = NULL;                                             \
-        if (GLOBAL_first_sg_fr == NULL)                                      \
-          GLOBAL_first_sg_fr = SG_FR;                                        \
+        if (Yap_first_sg_fr == NULL)                                      \
+          Yap_first_sg_fr = SG_FR;                                        \
         else                                                                 \
-          SgFr_next(GLOBAL_last_sg_fr) = SG_FR;                              \
-        GLOBAL_last_sg_fr = SG_FR
+          SgFr_next(Yap_last_sg_fr) = SG_FR;                              \
+        Yap_last_sg_fr = SG_FR
 #define remove_from_global_sg_fr_list(SG_FR)                                 \
         if (SgFr_previous(SG_FR)) {                                          \
           if ((SgFr_next(SgFr_previous(SG_FR)) = SgFr_next(SG_FR)) != NULL)  \
             SgFr_previous(SgFr_next(SG_FR)) = SgFr_previous(SG_FR);          \
           else                                                               \
-            GLOBAL_last_sg_fr = SgFr_previous(SG_FR);                        \
+            Yap_last_sg_fr = SgFr_previous(SG_FR);                        \
         } else {                                                             \
-          if ((GLOBAL_first_sg_fr = SgFr_next(SG_FR)) != NULL)               \
+          if ((Yap_first_sg_fr = SgFr_next(SG_FR)) != NULL)               \
             SgFr_previous(SgFr_next(SG_FR)) = NULL;                          \
           else                                                               \
-            GLOBAL_last_sg_fr = NULL;                                        \
+            Yap_last_sg_fr = NULL;                                        \
 	}                                                                    \
-        if (GLOBAL_check_sg_fr == SG_FR)                                     \
+        if (Yap_check_sg_fr == SG_FR)                                     \
           GLOBAL_check_sg_fr = SgFr_previous(SG_FR)
 #else
 #define insert_into_global_sg_fr_list(SG_FR)
@@ -652,7 +652,7 @@ static inline void abolish_incomplete_subgoals(choiceptr prune_cp) {
 
   if (EQUAL_OR_YOUNGER_CP(DepFr_cons_cp(LOCAL_top_dep_fr), prune_cp)) {
 #ifdef YAPOR
-    if (PARALLEL_EXECUTION_MODE)
+    if (Yap_parallel_execution_mode)
       pruning_over_tabling_data_structures();
 #endif /* YAPOR */
     do {
@@ -666,7 +666,7 @@ static inline void abolish_incomplete_subgoals(choiceptr prune_cp) {
   while (LOCAL_top_sg_fr && EQUAL_OR_YOUNGER_CP(SgFr_gen_cp(LOCAL_top_sg_fr), prune_cp)) {
     sg_fr_ptr sg_fr;
 #ifdef YAPOR
-    if (PARALLEL_EXECUTION_MODE)
+    if (Yap_parallel_execution_mode)
       pruning_over_tabling_data_structures();
 #endif /* YAPOR */
     sg_fr = LOCAL_top_sg_fr;
diff --git a/OPTYap/tab.tries.c b/OPTYap/tab.tries.c
index f3226c730..7cc6fe480 100644
--- a/OPTYap/tab.tries.c
+++ b/OPTYap/tab.tries.c
@@ -468,7 +468,7 @@ static void free_global_trie_branch(gt_node_ptr current_node) {
       if (num_nodes == 0) {
 	FREE_HASH_BUCKETS(Hash_buckets(hash));
 	FREE_GLOBAL_TRIE_HASH(hash);
-	if (parent_node != GLOBAL_root_gt) {
+	if (parent_node != Yap_root_gt) {
 #ifdef GLOBAL_TRIE_FOR_SUBTERMS
 	  if (mode == TRAVERSE_MODE_NORMAL) {
 	    if (IsApplTerm(t)) {
@@ -506,7 +506,7 @@ static void free_global_trie_branch(gt_node_ptr current_node) {
   } else if (TrNode_next(current_node) == NULL) {
     CHECK_DECREMENT_GLOBAL_TRIE_FOR_SUBTERMS_REFERENCE(t, mode);
     FREE_GLOBAL_TRIE_NODE(current_node);
-    if (parent_node != GLOBAL_root_gt) {
+    if (parent_node != Yap_root_gt) {
 #ifdef GLOBAL_TRIE_FOR_SUBTERMS
       if (mode == TRAVERSE_MODE_NORMAL) {
 	if (IsApplTerm(t)) {
@@ -804,7 +804,7 @@ static void traverse_global_trie(gt_node_ptr current_node, char *str, int str_in
 
 
 static void traverse_global_trie_for_term(gt_node_ptr current_node, char *str, int *str_index, int *arity, int *mode, int type) {
-  if (TrNode_parent(current_node) != GLOBAL_root_gt)
+  if (TrNode_parent(current_node) != Yap_root_gt)
     traverse_global_trie_for_term(TrNode_parent(current_node), str, str_index, arity, mode, type);
   traverse_trie_node(TrNode_entry(current_node), str, str_index, arity, mode, type);
   return;
@@ -1377,11 +1377,11 @@ void show_global_trie(int show_mode) {
   } else {  /* SHOW_MODE_STRUCTURE */
     fprintf(Yap_stdout, "Global trie structure\n");
   }
-  if (TrNode_child(GLOBAL_root_gt)) {
+  if (TrNode_child(Yap_root_gt)) {
     char *str = (char *) malloc(sizeof(char) * SHOW_TABLE_STR_ARRAY_SIZE);
     int *arity = (int *) malloc(sizeof(int) * SHOW_TABLE_ARITY_ARRAY_SIZE);
     arity[0] = 0;
-    traverse_global_trie(TrNode_child(GLOBAL_root_gt), str, 0, arity, TRAVERSE_MODE_NORMAL, TRAVERSE_POSITION_FIRST);
+    traverse_global_trie(TrNode_child(Yap_root_gt), str, 0, arity, TRAVERSE_MODE_NORMAL, TRAVERSE_POSITION_FIRST);
     free(str);
     free(arity);
   } else
diff --git a/OPTYap/tab.tries.i b/OPTYap/tab.tries.i
index 659f2cdc5..ec333ad0f 100644
--- a/OPTYap/tab.tries.i
+++ b/OPTYap/tab.tries.i
@@ -831,7 +831,7 @@ static inline sg_node_ptr subgoal_search_loop(tab_ent_ptr tab_ent, sg_node_ptr c
 ************************************************************************/
   CACHE_REGS
 #ifdef MODE_GLOBAL_TRIE_LOOP
-  gt_node_ptr current_node = GLOBAL_root_gt;
+  gt_node_ptr current_node = Yap_root_gt;
 #endif /* MODE_GLOBAL_TRIE_LOOP */
   int subs_arity = *subs_arity_ptr;
   CELL *stack_vars = *stack_vars_ptr;
@@ -856,7 +856,7 @@ static inline sg_node_ptr subgoal_search_loop(tab_ent_ptr tab_ent, sg_node_ptr c
 	if (subs_arity == MAX_TABLE_VARS)
 	  Yap_Error(INTERNAL_ERROR, TermNil, "subgoal_search_loop: MAX_TABLE_VARS exceeded");
 	STACK_PUSH_UP(t, stack_vars);
-	*((CELL *)t) = GLOBAL_table_var_enumerator(subs_arity);
+	*((CELL *)t) = Yap_table_var_enumerator(subs_arity);
 	t = MakeTableVarTerm(subs_arity);
 	subs_arity = subs_arity + 1;
 	SUBGOAL_CHECK_INSERT_ENTRY(tab_ent, current_node, t);
@@ -901,7 +901,7 @@ static inline sg_node_ptr subgoal_search_loop(tab_ent_ptr tab_ent, sg_node_ptr c
 	  STACK_PUSH_UP(t, stack_terms);
 	}
 #if defined(MODE_GLOBAL_TRIE_LOOP) && defined(GLOBAL_TRIE_FOR_SUBTERMS)
-      } else if (current_node != GLOBAL_root_gt) {
+      } else if (current_node != Yap_root_gt) {
 	gt_node_ptr entry_node = subgoal_search_global_trie_terms_loop(t, &subs_arity, &stack_vars, stack_terms);
 	current_node = global_trie_check_insert_gt_entry(current_node, (Term) entry_node);
 #endif /* MODE_GLOBAL_TRIE_LOOP && GLOBAL_TRIE_FOR_SUBTERMS */
@@ -918,13 +918,13 @@ static inline sg_node_ptr subgoal_search_loop(tab_ent_ptr tab_ent, sg_node_ptr c
 	STACK_PUSH_UP(Deref(aux_pair[0]), stack_terms);
       }
 #if defined(MODE_GLOBAL_TRIE_LOOP) && defined(GLOBAL_TRIE_FOR_SUBTERMS)
-    } else if (current_node != GLOBAL_root_gt) {
+    } else if (current_node != Yap_root_gt) {
       gt_node_ptr entry_node = subgoal_search_global_trie_terms_loop(t, &subs_arity, &stack_vars, stack_terms);
       current_node = global_trie_check_insert_gt_entry(current_node, (Term) entry_node);
 #endif /* MODE_GLOBAL_TRIE_LOOP && GLOBAL_TRIE_FOR_SUBTERMS */
 #else /* ! TRIE_COMPACT_PAIRS */
 #if defined(MODE_GLOBAL_TRIE_LOOP) && defined(GLOBAL_TRIE_FOR_SUBTERMS)
-    if (current_node != GLOBAL_root_gt) {
+    if (current_node != Yap_root_gt) {
       gt_node_ptr entry_node = subgoal_search_global_trie_terms_loop(t, &subs_arity, &stack_vars, stack_terms);
       current_node = global_trie_check_insert_gt_entry(current_node, (Term) entry_node);
     } else 
@@ -1035,7 +1035,7 @@ static inline ans_node_ptr answer_search_loop(sg_fr_ptr sg_fr, ans_node_ptr curr
 ************************************************************************/
   CACHE_REGS
 #ifdef MODE_GLOBAL_TRIE_LOOP
-  gt_node_ptr current_node = GLOBAL_root_gt;
+  gt_node_ptr current_node = Yap_root_gt;
 #endif /* MODE_GLOBAL_TRIE_LOOP */
   int vars_arity = *vars_arity_ptr;
 #if ! defined(MODE_GLOBAL_TRIE_LOOP) || ! defined(GLOBAL_TRIE_FOR_SUBTERMS)
@@ -1066,7 +1066,7 @@ static inline ans_node_ptr answer_search_loop(sg_fr_ptr sg_fr, ans_node_ptr curr
 	if (vars_arity == MAX_TABLE_VARS)
 	  Yap_Error(INTERNAL_ERROR, TermNil, "answer_search_loop: MAX_TABLE_VARS exceeded");
 	stack_vars_base[vars_arity] = t;
-	*((CELL *)t) = GLOBAL_table_var_enumerator(vars_arity);
+	*((CELL *)t) = Yap_table_var_enumerator(vars_arity);
 	t = MakeTableVarTerm(vars_arity);
 	ANSWER_CHECK_INSERT_ENTRY(sg_fr, current_node, t, _trie_retry_var + in_pair);
 	vars_arity = vars_arity + 1;
@@ -1118,7 +1118,7 @@ static inline ans_node_ptr answer_search_loop(sg_fr_ptr sg_fr, ans_node_ptr curr
 	  STACK_PUSH_UP(t, stack_terms);
 	}
 #if defined(MODE_GLOBAL_TRIE_LOOP) && defined(GLOBAL_TRIE_FOR_SUBTERMS)
-      } else if (current_node != GLOBAL_root_gt) {
+      } else if (current_node != Yap_root_gt) {
 	gt_node_ptr entry_node = answer_search_global_trie_terms_loop(t, &vars_arity, stack_terms);
 	current_node = global_trie_check_insert_gt_entry(current_node, (Term) entry_node);
 #endif /* MODE_GLOBAL_TRIE_LOOP && GLOBAL_TRIE_FOR_SUBTERMS */
@@ -1137,13 +1137,13 @@ static inline ans_node_ptr answer_search_loop(sg_fr_ptr sg_fr, ans_node_ptr curr
 	STACK_PUSH_UP(Deref(aux_pair[0]), stack_terms);
       }
 #if defined(MODE_GLOBAL_TRIE_LOOP) && defined(GLOBAL_TRIE_FOR_SUBTERMS)
-    } else if (current_node != GLOBAL_root_gt) {
+    } else if (current_node != Yap_root_gt) {
       gt_node_ptr entry_node = answer_search_global_trie_terms_loop(t, &vars_arity, stack_terms);
       current_node = global_trie_check_insert_gt_entry(current_node, (Term) entry_node);
 #endif /* MODE_GLOBAL_TRIE_LOOP && GLOBAL_TRIE_FOR_SUBTERMS */
 #else /* ! TRIE_COMPACT_PAIRS */
 #if defined(MODE_GLOBAL_TRIE_LOOP) && defined(GLOBAL_TRIE_FOR_SUBTERMS)
-    if (current_node != GLOBAL_root_gt) {
+    if (current_node != Yap_root_gt) {
       gt_node_ptr entry_node = answer_search_global_trie_terms_loop(t, &vars_arity, stack_terms);
       current_node = global_trie_check_insert_gt_entry(current_node, (Term) entry_node);
     } else 
diff --git a/VC/include/Yap.h b/VC/include/Yap.h
index 088896b17..4e08f1898 100644
--- a/VC/include/Yap.h
+++ b/VC/include/Yap.h
@@ -54,17 +54,17 @@
 #error Do not explicitly define YAPOR
 #endif /* YAPOR */
 
-#if (defined(ENV_COPY) && (defined(ACOW) || defined(SBA))) || (defined(ACOW) && defined(SBA))
+#if (defined(YAPOR_COPY) && (defined(YAPOR_COW) || defined(YAPOR_SBA))) || (defined(YAPOR_COW) && defined(YAPOR_SBA))
 #error Do not define multiple or-parallel models
-#endif /* (ENV_COPY && (ACOW || SBA)) || (ACOW && SBA) */
+#endif /* (YAPOR_COPY && (YAPOR_COW || YAPOR_SBA)) || (YAPOR_COW && YAPOR_SBA) */
 
-#if defined(ENV_COPY) || defined(ACOW) || defined(SBA)
+#if defined(YAPOR_COPY) || defined(YAPOR_COW) || defined(YAPOR_SBA)
 #define YAPOR 1
-#endif /* ENV_COPY || ACOW || SBA */
+#endif /* YAPOR_COPY || YAPOR_COW || YAPOR_SBA */
 
-#if defined(TABLING) && (defined(ACOW) || defined(SBA))
-#error Currently TABLING only works with ENV_COPY
-#endif /* TABLING && (ACOW || SBA) */
+#if defined(TABLING) && (defined(YAPOR_COW) || defined(YAPOR_SBA))
+#error Currently TABLING only works with YAPOR_COPY
+#endif /* TABLING && (YAPOR_COW || YAPOR_SBA) */
 
 #ifdef YAPOR
 #define FIXED_STACKS 1
@@ -86,7 +86,7 @@
 #endif
 #endif
 
-#ifdef SBA
+#ifdef YAPOR_SBA
 #ifdef YAPOR
 #ifndef FROZEN_STACKS
 #define FROZEN_STACKS 1
@@ -365,6 +365,7 @@ typedef CELL Term;
 
 #include "Regs.h"
 
+
 #if defined(YAPOR) ||defined(THREADS)
 #ifdef mips
 #include <locks_mips_funcs.h>
@@ -613,7 +614,7 @@ and  RefOfTerm(t) : Term -> DBRef = ...
 
 #else
 
-#if defined(SBA) && defined(__linux__)
+#if defined(YAPOR_SBA) && defined(__linux__)
 #define MBIT     /* 0x20000000 */ MKTAG(0x1,0)	/* mark bit */
 #else
 #define RBIT     /* 0x20000000 */ MKTAG(0x1,0)  /* relocation chain bit */
@@ -642,7 +643,7 @@ inline EXTERN Term * VarOfTerm(Term t)
 }
 
 
-#if SBA
+#if YAPOR_SBA
 
 inline EXTERN Term MkVarTerm(void);
 
@@ -825,8 +826,8 @@ inline EXTERN Int IntegerOfTerm(Term t)
 
 /*************** unification routines ***********************************/
 
-#if SBA
-#include "or.sbaamiops.h"
+#if YAPOR_SBA
+#include "or.sba_amiops.h"
 #else
 #include "amiops.h"
 #endif
@@ -1046,7 +1047,7 @@ extern int      snoozing;
 #include "opt.proto.h"
 #endif /* YAPOR || TABLING */
 
-#if SBA
-#include "or.sbaunify.h"
+#if YAPOR_SBA
+#include "or.sba_unify.h"
 #endif
 
diff --git a/VC/include/corout_utils.h b/VC/include/corout_utils.h
index 79b272365..7283e2c00 100644
--- a/VC/include/corout_utils.h
+++ b/VC/include/corout_utils.h
@@ -33,7 +33,7 @@ SDeref (Term a)
     {
       Term *b = (Term *) a;
       a = *b;
-#if SBA
+#if YAPOR_SBA
       if (a == (0))
 	return (CELL) b;
 #else
@@ -50,7 +50,7 @@ SDerefa (CELL * b)
   Term a = *b;
   while (IsVarTerm (a))
     {
-#if SBA
+#if YAPOR_SBA
       if (a == (0))
 	return (CELL) b;
 #else
@@ -69,7 +69,7 @@ SADerefa (CELL * b)
   Term a = *b;
   while (IsVarTerm (a))
     {
-#if SBA
+#if YAPOR_SBA
       if (a == (0))
 	return b;
 #else
diff --git a/configure b/configure
index c5f4c16fa..cb0bab7a8 100755
--- a/configure
+++ b/configure
@@ -7492,13 +7492,13 @@ fi
 
 case "$orparallelism" in
   sba)
-   YAP_EXTRAS="$YAP_EXTRAS -DSBA=1"
+   YAP_EXTRAS="$YAP_EXTRAS -DYAPOR_SBA=1"
   ;;
   a-cow)
-   YAP_EXTRAS="$YAP_EXTRAS -DACOW=1"
+   YAP_EXTRAS="$YAP_EXTRAS -DYAPOR_COW=1"
   ;;
   yes|env-copy)
-   YAP_EXTRAS="$YAP_EXTRAS -DENV_COPY=1"
+   YAP_EXTRAS="$YAP_EXTRAS -DYAPOR_COPY=1"
   ;;
 esac
 
diff --git a/configure.in b/configure.in
index 8b4647b57..b4a4fe504 100644
--- a/configure.in
+++ b/configure.in
@@ -1276,13 +1276,13 @@ fi
   
 case "$orparallelism" in
   sba)
-   YAP_EXTRAS="$YAP_EXTRAS -DSBA=1"
+   YAP_EXTRAS="$YAP_EXTRAS -DYAPOR_SBA=1"
   ;;
   a-cow)
-   YAP_EXTRAS="$YAP_EXTRAS -DACOW=1"
+   YAP_EXTRAS="$YAP_EXTRAS -DYAPOR_COW=1"
   ;;
   yes|env-copy)
-   YAP_EXTRAS="$YAP_EXTRAS -DENV_COPY=1"
+   YAP_EXTRAS="$YAP_EXTRAS -DYAPOR_COPY=1"
   ;;
 esac
 
diff --git a/console/yap.c b/console/yap.c
index e9137f1ab..b404b0502 100644
--- a/console/yap.c
+++ b/console/yap.c
@@ -149,14 +149,14 @@ print_usage(void)
 #ifdef TABLING
   fprintf(stderr,"  -ts  Maximum table space area in Mbytes (default: unlimited)\n");
 #endif /* TABLING */
-#if defined(ENV_COPY) || defined(ACOW) || defined(SBA)
+#if defined(YAPOR_COPY) || defined(YAPOR_COW) || defined(YAPOR_SBA)
   fprintf(stderr,"  -w   Number of workers (default: %d)\n",
 	  DEFAULT_NUMBERWORKERS);
   fprintf(stderr,"  -sl  Loop scheduler executions before look for hiden shared work (default: %d)\n", 
           DEFAULT_SCHEDULERLOOP);
   fprintf(stderr,"  -d   Value of delayed release of load (default: %d)\n",
 	  DEFAULT_DELAYEDRELEASELOAD);
-#endif /* ENV_COPY || ACOW || SBA */
+#endif /* YAPOR_COPY || YAPOR_COW || YAPOR_SBA */
   /* nf: Preprocessor */		
   /* fprintf(stderr,"  -DVar=Name   Persistent definition\n"); */
   fprintf(stderr,"\n");
@@ -245,7 +245,7 @@ parse_yap_arguments(int argc, char *argv[], YAP_init_args *iap)
           case 'q':
 	    iap->QuietMode = TRUE;
 	    break;
-#if defined(ENV_COPY) || defined(ACOW) || defined(SBA)
+#if defined(YAPOR_COPY) || defined(YAPOR_COW) || defined(YAPOR_SBA)
 	  case 'w':
 	    ssize = &(iap->NumberWorkers);
 	    goto GetSize;
@@ -258,7 +258,7 @@ parse_yap_arguments(int argc, char *argv[], YAP_init_args *iap)
           case 'd':
 	    if (!strcmp("dump-runtime-variables",p))
 		return dump_runtime_variables();
-#endif /* ENV_COPY || ACOW || SBA */
+#endif /* YAPOR_COPY || YAPOR_COW || YAPOR_SBA */
 #ifdef USE_SOCKET
           case 'c':          /* running as client */
 	    {
@@ -386,12 +386,12 @@ parse_yap_arguments(int argc, char *argv[], YAP_init_args *iap)
 	  case 's':
 	  case 'S':
 	    ssize = &(iap->StackSize);
-#if defined(ENV_COPY) || defined(ACOW) || defined(SBA)
+#if defined(YAPOR_COPY) || defined(YAPOR_COW) || defined(YAPOR_SBA)
 	    if (p[1] == 'l') {
 	      p++;
 	      ssize = &(iap->SchedulerLoop);
 	    }
-#endif /* ENV_COPY || ACOW || SBA */
+#endif /* YAPOR_COPY || YAPOR_COW || YAPOR_SBA */
 	    goto GetSize;
 	  case 'a':
 	  case 'A':
diff --git a/misc/GLOBALS b/misc/GLOBALS
index dcdda4f65..703f85f55 100644
--- a/misc/GLOBALS
+++ b/misc/GLOBALS
@@ -19,49 +19,44 @@
 
 
 // Stuff that must be shared by all threads or workers
-START_WORKER_SHARED
+START_GLOBAL_DATA
 
 /* multi-thread support */
 #if THREADS
 /* number of threads and processes in system */
-UInt		n_of_threads		NOfThreads	=1
+UInt		n_of_threads		Yap_NOfThreads	=1
 /* number of threads created since start */
-UInt		n_of_threads_created	NOfThreadsCreated =1
+UInt		n_of_threads_created	Yap_NOfThreadsCreated =1
 /* total run time for dead threads */
-UInt  threads_total_time		ThreadsTotalTime =0L
+UInt  threads_total_time		Yap_ThreadsTotalTime =0L
 #endif
 
 // multi-thread/ORP support
 #if defined(YAPOR) || defined(THREADS)
 // protect long critical regions
-lockvar		bgl			BGL		MkLock
+lockvar		bgl			Yap_BGL		MkLock
 #endif
 
 // stack overflow expansion/gc control
 int		allow_local_expansion	Yap_AllowLocalExpansion =TRUE
 int		allow_global_expansion	Yap_AllowGlobalExpansion =TRUE
 int		allow_trail_expansion	Yap_AllowTrailExpansion =TRUE
-UInt		size_of_overflow	SizeOfOverflow		=0
+UInt		size_of_overflow	Yap_SizeOfOverflow		=0
 // amount of space recovered in all garbage collections
-UInt		agc_last_call		AGcLastCall		=0
+UInt		agc_last_call		Yap_AGcLastCall		=0
 // amount of space recovered in all garbage collections
-UInt		agc_threshold		AGcThreshold		=10000
-Agc_hook	agc_hook		AGCHook			=NULL
+UInt		agc_threshold		Yap_AGcThreshold		=10000
+Agc_hook	agc_hook		Yap_AGCHook			=NULL
 
-// readline
-#if HAVE_LIBREADLINE
-char		*readline_buf		ReadlineBuf		=NULL
-char		*readline_pos		ReadlinePos		=0L
-#endif
 
 // Threads Array
 #ifdef THREADS
-lockvar		thread_handles_lock	ThreadHandlesLock	MkLock
+lockvar		thread_handles_lock	Yap_ThreadHandlesLock	MkLock
 #endif 
 
 // Ricardo's stuff
 #if defined(YAPOR) || defined(TABLING)
-struct global_data	global			GLOBAL		void	
+struct optyap_global_data	optyap_data	Yap_optyap_data	void	
 struct local_data	remote[MAX_WORKERS]	REMOTE		void
 #endif
 
@@ -74,5 +69,5 @@ char	      **pl_argv			Yap_PL_Argv		=NULL
 // halt hooks
 struct halt_hook *yap_halt_hook		Yap_HaltHooks		=NULL
 
-END_WORKER_SHARED
+END_GLOBAL_DATA
 
diff --git a/misc/LOCALS b/misc/LOCALS
index 01464c803..b16b4c798 100644
--- a/misc/LOCALS
+++ b/misc/LOCALS
@@ -106,7 +106,7 @@ CELL**				ip_top		iptop		=NULL
 #if GC_NO_TAGS
 char*				b_p		Yap_bp		=NULL
 #endif
-#if defined(TABLING) || defined(SBA)
+#if defined(TABLING) || defined(YAPOR_SBA)
 struct trail_frame*		wl_sTR		sTR		=NULL
 struct trail_frame*		wl_sTR0		sTR0		=NULL
 struct trail_frame*		new_tr		new_TR		=NULL
diff --git a/misc/buildheap b/misc/buildheap
index 476e9f05d..cb34dd679 100644
--- a/misc/buildheap
+++ b/misc/buildheap
@@ -51,10 +51,10 @@ gen_struct(Inp,Out) :-
 	Inp = "END_WORKER_LOCAL", !,
 	Out = "} w_local;".
 gen_struct(Inp,Out) :-
-	Inp = "START_WORKER_SHARED", !,
-	Out = "typedef struct worker_shared {".
+	Inp = "START_GLOBAL_DATA", !,
+	Out = "typedef struct global_data {".
 gen_struct(Inp,Out) :-
-	Inp = "END_WORKER_SHARED", !,
+	Inp = "END_GLOBAL_DATA", !,
 	Out = "} w_shared;".
 gen_struct(Inp,Out) :-
 	Inp = "ATOMS", !,
@@ -87,10 +87,10 @@ gen_dstruct(Inp,"") :-
 	Inp = "END_WORKER_LOCAL", !,
 	retract(globals(worker)).
 gen_dstruct(Inp,"") :-
-	Inp = "START_WORKER_SHARED", !,
+	Inp = "START_GLOBAL_DATA", !,
 	assert(globals(all)).
 gen_dstruct(Inp,"") :-
-	Inp = "END_WORKER_SHARED", !,
+	Inp = "END_GLOBAL_DATA", !,
 	retract(globals(all)).
 gen_dstruct(Inp,Out) :-
 	Inp = "ATOMS", !,
@@ -122,7 +122,7 @@ fetch_name(Global) :-
 	Global = "WL->".
 fetch_name(Global) :-
 	globals(worker_init), !,
-	Global = "FOREIGN_WL(wid)->".
+	Global = "FOREIGN(wid)->".
 fetch_name(Global) :-
 	Global = "Yap_heap_regs->".
 
@@ -156,11 +156,11 @@ gen_hstruct(Inp,Out) :-
 	Out = "}",
 	retract(globals(worker_init)).
 gen_hstruct(Inp,Out) :-
-	Inp = "START_WORKER_SHARED", !,
+	Inp = "START_GLOBAL_DATA", !,
 	Out = "static void RestoreGlobal(void) {",
 	assert(globals(all)).
 gen_hstruct(Inp,Out) :-
-	Inp = "END_WORKER_SHARED", !,
+	Inp = "END_GLOBAL_DATA", !,
 	Out = "}",
 	retract(globals(all)).
 gen_hstruct(Inp, Out) :-
@@ -235,11 +235,11 @@ gen_init(Inp,Out) :-
 	Out = "}",
 	retract(globals(worker_init)).
 gen_init(Inp,Out) :-
-	Inp = "START_WORKER_SHARED", !,
+	Inp = "START_GLOBAL_DATA", !,
 	Out = "static void InitGlobal(void) {",
 	assert(globals(all)).
 gen_init(Inp,Out) :-
-	Inp = "END_WORKER_SHARED", !,
+	Inp = "END_GLOBAL_DATA", !,
 	Out = "}",
 	retract(globals(all)).
 gen_init(Inp,Out) :-