diff --git a/C/load_dl.c b/C/load_dl.c
index 5edeb56da..10b2b0e50 100755
--- a/C/load_dl.c
+++ b/C/load_dl.c
@@ -133,7 +133,7 @@ LoadForeign(StringList ofiles, StringList libs,
 
     ofiles->handle = handle;
 
-    if (!*init_proc)
+    if (proc_name && !*init_proc)
       *init_proc = (YapInitProc) dlsym(handle,proc_name);
 
     ofiles = ofiles->next;
diff --git a/C/load_foreign.c b/C/load_foreign.c
index 13c86b782..ead46aa76 100755
--- a/C/load_foreign.c
+++ b/C/load_foreign.c
@@ -261,7 +261,8 @@ Yap_ReOpenLoadForeign(void)
   while (f_code != NULL) {
     CurrentModule = f_code->module;
     if(Yap_ReLoadForeign(f_code->objs,f_code->libs,f_code->f,&InitProc)==LOAD_SUCCEEDED) {
-      (*InitProc)();
+      if (InitProc)
+	(*InitProc)();
     }
     f_code = f_code->next;
   }
diff --git a/include/SWI-Prolog.h b/include/SWI-Prolog.h
index d439a1ca6..5ccbdafd9 100755
--- a/include/SWI-Prolog.h
+++ b/include/SWI-Prolog.h
@@ -513,8 +513,8 @@ extern X_API int PL_recorded_external(char *, term_t);
 extern X_API int PL_erase_external(char *);
 extern X_API int PL_action(int,...);
 extern X_API void PL_on_halt(void (*)(int, void *), void *);
-extern X_API void *PL_malloc(int);
-extern X_API void *PL_realloc(void*,int);
+extern X_API void *PL_malloc(size_t);
+extern X_API void *PL_realloc(void*,size_t);
 extern X_API void PL_free(void *);
 extern X_API int  PL_eval_expression_to_int64_ex(term_t t, int64_t *val);
 extern X_API void  PL_cleanup_fork(void);
diff --git a/library/yap2swi/yap2swi.c b/library/yap2swi/yap2swi.c
index 7f4572cb1..aff9330bb 100755
--- a/library/yap2swi/yap2swi.c
+++ b/library/yap2swi/yap2swi.c
@@ -272,8 +272,8 @@ ensure_space(char **sp, size_t room, unsigned flags) {
     min += 512;
 
   if (flags & BUF_MALLOC) {
-    free(*sp);
-    *sp = malloc(room);
+    PL_free(*sp);
+    *sp = PL_malloc(room);
     return *sp; 
   } else if (flags & BUF_RING) {
     for (i=1; i<= SWI_BUF_RINGS; i++)
@@ -512,7 +512,7 @@ static int do_yap_putc(int sno, wchar_t ch) {
     UInt bufsize = putc_cur_lim-putc_cur_buf;
     UInt bufpos = putc_curp-putc_cur_buf;
 
-    if (!(putc_cur_buf = realloc(putc_cur_buf, bufsize+SWI_BUF_SIZE))) {
+    if (!(putc_cur_buf = PL_realloc(putc_cur_buf, bufsize+SWI_BUF_SIZE))) {
       /* we can+t go forever */
       return FALSE;
     }
@@ -564,7 +564,7 @@ X_API int PL_get_chars(term_t l, char **sp, unsigned flags)
   if ((flags & BUF_RING)) {
     tmp = alloc_ring_buf();
   } else if ((flags & BUF_MALLOC)) {
-    tmp = malloc(SWI_BUF_SIZE);
+    tmp = PL_malloc(SWI_BUF_SIZE);
   } else {
     tmp = SWI_buffers[0];
   }
@@ -641,7 +641,7 @@ X_API int PL_get_chars(term_t l, char **sp, unsigned flags)
   }
   if (flags & BUF_MALLOC) {
     size_t sz = strlen(tmp);
-    char *nbf = malloc(sz+1);
+    char *nbf = PL_malloc(sz+1);
     if (!nbf)
       return 0;
     strncpy(nbf,tmp,sz+1);
@@ -685,7 +685,7 @@ X_API int PL_get_wchars(term_t l, size_t *len, wchar_t **wsp, unsigned flags)
   }
   room = (sz+1)*sizeof(wchar_t);
   if (flags & BUF_MALLOC) {
-    *wsp = buf = (wchar_t *)malloc(room);
+    *wsp = buf = (wchar_t *)PL_malloc(room);
   } else if (flags & BUF_RING) {
     *wsp = (wchar_t *)alloc_ring_buf();
     buf = (wchar_t *)ensure_space((char **)wsp, room, flags);
@@ -3011,21 +3011,33 @@ PL_set_engine(PL_engine_t engine, PL_engine_t *old)
 
 
 X_API void *
-PL_malloc(int sz)
+PL_malloc(size_t sz)
 {
-  return (void *)Yap_AllocCodeSpace((long unsigned int)sz);
+  if ( sz == 0 )
+    return NULL;
+  return (void *)malloc((long unsigned int)sz);
 }
 
 X_API void *
-PL_realloc(void *ptr, int sz)
+PL_realloc(void *ptr, size_t sz)
 {
-  return Yap_ReallocCodeSpace((char *)ptr,(long unsigned int)sz);
+  if (ptr) {
+    if (sz) {
+      return realloc((char *)ptr,(long unsigned int)sz);
+    } else {
+      free(ptr);
+      return NULL;
+    }
+  } else {
+    return PL_malloc(sz);
+  }
 }
 
 X_API void
 PL_free(void *obj)
 {
-  return Yap_FreeCodeSpace((char *)obj);
+  if (obj)
+    free(obj);
 }
 
 X_API int
diff --git a/packages/clib/process.pl b/packages/clib/process.pl
index 0e600a9eb..9950d38c7 100644
--- a/packages/clib/process.pl
+++ b/packages/clib/process.pl
@@ -45,6 +45,8 @@
 :- use_module(library(option)).
 :- use_module(library(error)).
 
+:- use_module(library(maplist)).
+
 :- use_foreign_library(foreign(process)).
 
 /** <module> Create processes and redirect I/O
diff --git a/pl/utils.yap b/pl/utils.yap
index eb5f705b0..bf31e3640 100644
--- a/pl/utils.yap
+++ b/pl/utils.yap
@@ -220,9 +220,17 @@ cd :-
 
 ls :-
 	getcwd(X),
-	system:directory_files(X, L),
+	'$load_system_ls'(X,L),
 	'$do_print_files'(L).
 
+'$load_system_ls'(X,L) :-
+	'$undefined'(directory_files(X, L), operating_system_support),
+	load_files(library(system),[silent(true)]),
+	fail.
+'$load_system_ls'(X,L) :-
+	operating_system_support:directory_files(X, L).
+	
+
 '$do_print_files'([]) :-
 	nl.
 '$do_print_files'([F| Fs]) :-
diff --git a/pl/yio.yap b/pl/yio.yap
index 9a406d509..89d1510b1 100644
--- a/pl/yio.yap
+++ b/pl/yio.yap
@@ -1209,3 +1209,21 @@ with_output_to(Output, Command) :-
 	atom_codes(Char, [Code]),
 	'$codes_to_chars'(String0, String, Chars).
 
+prolog_to_os_filename(Prolog, OS) :-
+	'$undefined'(swi_prolog_to_os_filename(Prolog, OS), system),
+	'$current_module'(Old, system),
+	load_foreign_files([libplstream], [], initIO),
+	'$current_module'(system, Old),
+	fail.
+prolog_to_os_filename(Prolog, OS) :-
+	system:swi_prolog_to_os_filename(Prolog, OS).
+
+
+
+
+
+
+
+
+
+