diff --git a/C/c_interface.c b/C/c_interface.c
index aafa2b0f6..8a01cc8e3 100755
--- a/C/c_interface.c
+++ b/C/c_interface.c
@@ -2122,7 +2122,7 @@ X_API int YAP_InitConsult(int mode, const char *fname, char *full, int *osnop) {
     }
   }
   bool consulted = (mode == YAP_CONSULT_MODE);
-  sno = Yap_OpenStream(fl, "r", MkAtomTerm(Yap_LookupAtom(fl)));
+  sno = Yap_OpenStream(fl, "r", MkAtomTerm(Yap_LookupAtom(fl)), LOCAL_encoding);
     if (sno < 0)
         return sno;
   if (!Yap_ChDir(dirname((char *)fl))) return -1;
diff --git a/C/dbase.c b/C/dbase.c
index b776ed244..b94ce8954 100644
--- a/C/dbase.c
+++ b/C/dbase.c
@@ -4913,11 +4913,15 @@ static Int cont_current_key_integer(USES_REGS1) {
 
 Term Yap_FetchTermFromDB(void *ref) {
   CACHE_REGS
+    if (ref == NULL)
+      return 0;
   return GetDBTerm(ref, FALSE PASS_REGS);
 }
 
 Term Yap_FetchClauseTermFromDB(void *ref) {
   CACHE_REGS
+    if (ref == NULL)
+      return 0;
   return GetDBTerm(ref, TRUE PASS_REGS);
 }
 
diff --git a/C/yap-args.c b/C/yap-args.c
index 3176b95c2..8e5832bcf 100755
--- a/C/yap-args.c
+++ b/C/yap-args.c
@@ -149,7 +149,10 @@ const char *Yap_BINDIR, *Yap_ROOTDIR, *Yap_SHAREDIR, *Yap_LIBDIR, *Yap_DLLDIR,
     *Yap_PLDIR, *Yap_BOOTSTRAP, *Yap_COMMONSDIR, *Yap_STARTUP,
     *Yap_INPUT_STARTUP, *Yap_OUTPUT_STARTUP, *Yap_BOOTFILE, *Yap_INCLUDEDIR;
 
-/* do initial boot by consulting the file boot.yap */
+/**
+ * consult loop in C: used to boot the system, butt supports goal execution and recursive consulting.
+ *
+ * */
 static void consult(const char *b_file USES_REGS) {
   Term t;
   int c_stream, osno, oactive;
@@ -157,7 +160,7 @@ static void consult(const char *b_file USES_REGS) {
   Functor functor_command1 = Yap_MkFunctor(Yap_LookupAtom(":-"), 1);
   Functor functor_compile2 = Yap_MkFunctor(Yap_LookupAtom("c_compile"), 1);
 
-  /* consult boot.pl */
+  /* consult in C */
   int lvl = push_text_stack();
   char *full = Malloc(YAP_FILENAME_MAX + 1);
   full[0] = '\0';
diff --git a/CXX/CMakeLists.txt b/CXX/CMakeLists.txt
index d29e8b7ec..168e84cef 100644
--- a/CXX/CMakeLists.txt
+++ b/CXX/CMakeLists.txt
@@ -5,7 +5,7 @@ set(SO_MINOR 0)
 set(SO_PATCH 0)
 
 set (CXX_SOURCES
-    yapi.cpp 
+    yapi.cpp
 )
 list(APPEND LIBYAP_SOURCES ${CXX_SOURCES} PARENT_SCOPE)
 
@@ -15,7 +15,7 @@ if ( WIN32 OR ANDROID)
   set_property( DIRECTORY  APPEND PROPERTY COMPILE_DEFINITIONS  "_YAP_NOT_INSTALLED_=1;HAVE_CONFIG_H=1;_GNU_SOURCE;YAP_KERNEL=1" )
 else()
    add_lib(YAP++ ${CXX_SOURCES} )
-   target_link_libraries(YAP++ ${CMAKE_DL_LIBS} libYap)
+   target_link_libraries(YAP++ ${CMAKE_DL_LIBS} Py4YAP libYap)
 
    MY_install(TARGETS  YAP++
      LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
diff --git a/CXX/yapi.cpp b/CXX/yapi.cpp
index 39ca33f3c..f8a08e8ca 100644
--- a/CXX/yapi.cpp
+++ b/CXX/yapi.cpp
@@ -10,6 +10,10 @@ extern "C" {
 #include "android/log.h"
 #endif
 
+#if 1
+#include "Python.h"
+#endif
+
 #include "YapInterface.h"
 #include "YapBlobs.h"
 #include "iopreds.h"
@@ -238,7 +242,6 @@ Term &YAPTerm::operator[](arity_t i) {
     else if (i == 1)
       tf = TailOfTerm(t0);
     RECOVER_MACHINE_REGS();
-    tf = RepPair(tf)[i];
   } else {
       Yap_Error(TYPE_ERROR_COMPOUND, t0, "");
  }
@@ -252,6 +255,7 @@ Term &YAPListTerm::operator[](arity_t i) {
   Term tf = 0;
   while (IsPairTerm(t0)) {
     if (i == 0) {
+
       tf = HeadOfTerm(t0);
       break;
     } else {
@@ -436,7 +440,10 @@ bool YAPEngine::call(YAPPredicate ap, YAPTerm ts[]) {
       //q.e = new YAPError();
     }
     // don't forget, on success these bindings will still be there);
+    PyThreadState *tstate;
+Py_BEGIN_ALLOW_THREADS
     result = YAP_LeaveGoal(false, &q);
+    Py_END_ALLOW_THREADS
     Yap_CloseHandles(q.CurSlot);
     LOCAL_RestartEnv = oj;
     RECOVER_MACHINE_REGS();
@@ -453,6 +460,9 @@ bool YAPEngine::call(YAPPredicate ap, YAPTerm ts[]) {
 
 bool YAPEngine::mgoal(Term t, Term tmod) {
   sigjmp_buf buf, *oldp = LOCAL_RestartEnv;
+  PyThreadState *_save;
+
+  _save = PyEval_SaveThread();
   try {
     CACHE_REGS
     BACKUP_MACHINE_REGS();
@@ -479,15 +489,16 @@ bool YAPEngine::mgoal(Term t, Term tmod) {
     // allow Prolog style exception handling
     LOCAL_RestartEnv = &buf;
     if (sigsetjmp(*LOCAL_RestartEnv, false)) {
-        std::cerr << "Restart\n";
+      PyEval_RestoreThread(_save);
+  std::cerr << "Restart\n";
         //throw new YAPError();
     }
     // don't forget, on success these guys may create slots
     __android_log_print(ANDROID_LOG_INFO, "YAPDroid", "exec  ");
-
     result = (bool)YAP_EnterGoal(ap, nullptr, &q);
     {
       YAP_LeaveGoal(false, &q);
+      PyEval_RestoreThread(_save);
       LOCAL_RestartEnv = oldp;
       RECOVER_MACHINE_REGS();
       return result;
@@ -495,7 +506,8 @@ bool YAPEngine::mgoal(Term t, Term tmod) {
   } catch (YAPError e) {
     YAP_LeaveGoal(false, &q);
     Yap_CloseHandles(q.CurSlot);
-    LOCAL_RestartEnv = oldp;
+    PyEval_RestoreThread(_save);
+  LOCAL_RestartEnv = oldp;
     return 0;
     //throw e;
   }
@@ -745,8 +757,8 @@ PredEntry *YAPEngine::rewriteUndefEngineQuery(PredEntry *a, Term &tgoal,
   ARG1 = tgoal = Yap_MkApplTerm(FunctorModule, 2, ts);
   //goal = YAPTerm(Yap_MkApplTerm(FunctorMetaCall, 1, &ARG1));
   return PredCall;
-  
-  
+
+
   // return YAPApplTerm(FunctorUndefinedQuery, ts);
 }
 
diff --git a/cmake/anaconda.cmake b/cmake/anaconda.cmake
new file mode 100644
index 000000000..4c2693122
--- /dev/null
+++ b/cmake/anaconda.cmake
@@ -0,0 +1,73 @@
+    set (PYTHONLIBS_FOUND YES CACHE BOOL "MINGW/MSYS2" FORCE )
+    set (PYTHON_LIBRARY $ENV{PREFIX}/lib/libpython$ENV{PY_VER}m.$ENV{SHLIB_EXT} CACHE FILEPATH "MINGW/MSYS2" FORCE )
+    set (PYTHON_LIBRARIES ${PYTHON_LIBRARY} CACHE FILEPATH "MINGW/MSYS2" FORCE )
+    set (PYTHON_INCLUDE_PATH $ENV{PREFIX}/include/python$ENV{PY_VER}m CACHE PATH "MINGW/MSYS2" FORCE )
+    set (PYTHON_INCLUDE_DIRS ${PYTHON_INCLUDE_PATH} CACHE PATH "MINGW/MSYS2" FORCE  )
+    set (PYTHON_EXECUTABLE $ENV{PREFIX}/bin/python CACHE FILEPATH "MINGW/MSYS2" FORCE )
+    set (PYTHONLIBS_VERSION_STRING $ENV{PY_VER} CACHE STRING "MINGW/MSYS2" FORCE )
+
+
+    # # try to extract R from readline to avoid collision
+    set(READLINE_INCLUDE_DIR $ENV{PREFIX}/include CACHE PATH "readline" FORCE)
+
+
+    # Apple readline does not support readline hooks
+    # So we look for another one by default
+    set(READLINE_readline_LIBRARY $ENV{PREFIX}/lib/libreadline.$ENV{SHLIB_EXT} CACHE PATH "readline")
+
+    # Sometimes readline really needs ncurses
+    set(READLINE_ncurses_LIBRARY  $ENV{PREFIX}/lib/libncurses.$ENV{SHLIB_EXT} CACHE PATH "readline")
+
+    set(READLINE_ncursesw_LIBRARY $ENV{PREFIX}/lib/libncursesw.$ENV{SHLIB_EXT} CACHE PATH "readline")
+
+    # Sometimes ncurses really needs terminfo
+    set(READLINE_tinfo_LIBRARY  $ENV{PREFIX}/lib/libntinfo.$ENV{SHLIB_EXT} CACHE PATH "readline")
+
+    set(READLINE_tinfow_LIBRARY  $ENV{PREFIX}/lib/libntinfow.$ENV{SHLIB_EXT} CACHE PATH "readline")
+
+    SET( READLINE_FOUND "YES" CACHE BOOL "Readline ACCESS.")
+
+
+    # Apple readline does not support readline hooks
+    # So we look for another one by default
+    if ( READLINE_readline_LIBRARY)
+        set (HAVE_LIBREADLINE YES CACHE BOOL "ibReadline ACCESS")
+    endif()
+
+    IF(READLINE_readline_LIBRARY)
+        set(HAVE_LIBREADLINE CACHE YES BOOL "Readline works." )
+        SET( READLINE_LIBRARIES
+                ${READLINE_readline_LIBRARY}
+                )
+
+        # some readline libraries depend on ncurses
+        IF(READLINE_ncurses_LIBRARY)
+            list(APPEND READLINE_LIBRARIES ${READLINE_ncurses_LIBRARY})
+        endif ()
+
+        # some readline libraries depend on ncurses
+        IF(READLINE_ncursesw_LIBRARY)
+            list(APPEND READLINE_LIBRARIES ${READLINE_ncursesw_LIBRARY})
+        endif ()
+
+        # some readline libraries depend on tinfo
+        IF(READLINE_tinfo_LIBRARY)
+            list(APPEND READLINE_LIBRARIES ${READLINE_tinfo_LIBRARY})
+        endif ()
+
+
+        # some readline libraries depend on tinfo
+        IF(READLINE_tinfow_LIBRARY)
+            list(APPEND READLINE_LIBRARIES ${READLINE_tinfow_LIBRARY})
+        endif ()
+
+        IF(READLINE_INCLUDE_DIR)
+            SET( READLINE_FOUND "YES" CACHE BOOL "Readline ACCESS.")
+        ENDIF(READLINE_INCLUDE_DIR)
+    ENDIF(READLINE_readline_LIBRARY)
+
+
+    set (GMP_INCLUDE_DIRS $ENV{PREFIX}/include)
+    set (GMP_LIBRARIES $ENV{PREFIX}/lib/libgmp.${SHLIB_EXT})
+    set (GMP_FOUND ON)
+    set (GMP_LIBRARIES_DIR $ENV{PREFIX}/lib)
\ No newline at end of file
diff --git a/include/SWI-Prolog.h b/include/SWI-Prolog.h
index a66e3e727..fe8ddcb19 100755
--- a/include/SWI-Prolog.h
+++ b/include/SWI-Prolog.h
@@ -44,7 +44,6 @@ extern "C" {
 #include <config.h>
 #else
 #include <Yap/YapInterface.h>
-#include <Yap/pl/config.h>
 #endif
 #endif
 #include <stdarg.h>
diff --git a/include/VFS.h b/include/VFS.h
index 5dd389534..8b9c8c24e 100644
--- a/include/VFS.h
+++ b/include/VFS.h
@@ -79,8 +79,9 @@ typedef struct vfs {
   const char *suffix;
   bool (*chDir)(struct vfs *me, const char *s);
   /** operations */
-  void *(*open)(struct vfs *, int sno, const char *fname,
-                const char *io_mode); /// open an object
+  void *(*open)(struct vfs *, const char *fname,
+                const char *io_mode,
+		int sno); /// open an object
   /// in this space, usual w,r,a,b flags plus B (store in a buffer)
   bool (*close)(int sno);           /// close the object
   int (*get_char)(int sno);         /// get an octet from the stream
diff --git a/library/lammpi/CMakeLists.txt b/library/lammpi/CMakeLists.txt
index fcb67ba15..88b59f7a5 100644
--- a/library/lammpi/CMakeLists.txt
+++ b/library/lammpi/CMakeLists.txt
@@ -1,10 +1,11 @@
 
-set (MPI_SOURCES
+set (MPI_YAP_SOURCES
   hash.c prologterms2c.c yap_mpi.c)
 
   macro_optional_find_package(MPI ON)
-  
-if (MPI_C_FOUND)
+
+  if (MPI_FOUND)
+    if (MPI_C_FOUND)
   # === Variables ===
   #
   # This module will set the following variables per language in your
@@ -67,7 +68,7 @@ if (MPI_C_FOUND)
   # pass to the MPI program.
   #
 
-  add_lib (yap_mpi ${MPI_SOURCES})
+  add_executable (yap_mpi ${MPI_YAP_SOURCES} Yaplib ../../console/yap.c)
 
   target_link_libraries(yap_mpi libYap ${MPI_C_LIBRARIES})
 
@@ -76,11 +77,11 @@ if (MPI_C_FOUND)
   include_directories (${MPI_C_INCLUDE_PATH})
 
   add_definitions (-DHAVE_MPI_H=1)
+    target_compile_definitions(yap_mpi  ${MPI_C_COMPILE_FLAGS})
 
   install(TARGETS  yap_mpi
-    LIBRARY DESTINATION ${YAP_INSTALL_DLLDIR}
-    RUNTIME DESTINATION ${YAP_INSTALL_DLLDIR}
-    ARCHIVE DESTINATION ${YAP_INSTALL_DLLDIR}
+    RUNTIME DESTINATION ${YAP_INSTALL_BDIR}
     )
 
-endif (MPI_C_FOUND)
+  endif (MPI_C_FOUND)
+endif (MPI_FOUND)
diff --git a/os/fmem.c b/os/fmem.c
index 1d1b46f61..fa5e29cef 100644
--- a/os/fmem.c
+++ b/os/fmem.c
@@ -152,7 +152,7 @@ int Yap_open_buf_read_stream(const char *buf, size_t nchars, encoding_t *encp,
   // like any file stream.
   f = st->file = fmemopen((void *)buf, nchars, "r");
   flags = Input_Stream_f | InMemory_Stream_f | Seekable_Stream_f;
-  Yap_initStream(sno, f, NULL, TermNil, encoding, flags, AtomRead, NULL);
+    Yap_initStream(sno, f, "memStream", "r", buf, encoding, flags, NULL);
   // like any file stream.
   Yap_DefaultStreamOps(st);
   UNLOCK(st->streamlock);
diff --git a/os/iopreds.c b/os/iopreds.c
index 6ff25467b..c5e69f6f1 100644
--- a/os/iopreds.c
+++ b/os/iopreds.c
@@ -406,16 +406,8 @@ static void InitStdStream(int sno, SMALLUNSGN flags, FILE *file, VFS_t *vfsp) {
   s->buf.on = false;
   s->encoding = ENC_ISO_UTF8;
   INIT_LOCK(s->streamlock);
-  if (vfsp != NULL) {
-    s->u.private_data = vfsp->open(vfsp, sno, vfsp->name,
-                                   (sno == StdInStream ? "read" : "write"));
-    if (s->u.private_data == NULL) {
-      (PlIOError(EXISTENCE_ERROR_SOURCE_SINK, MkIntTerm(sno), "%s",
-                 vfsp->name));
-      return;
-    }
-  } else {
-    unix_upd_stream_info(s);
+  if (vfsp == NULL) {
+     unix_upd_stream_info(s);
   }
   /* Getting streams to prompt is a mess because we need for cooperation
      between readers and writers to the stream :-(
@@ -1133,11 +1125,23 @@ static void check_bom(int sno, StreamDesc *st) {
   }
 }
 
-bool Yap_initStream(int sno, FILE *fd, const char *name, Term file_name,
-                    encoding_t encoding, stream_flags_t flags, Atom open_mode,
-                    void *vfs) {
+bool Yap_initStream(int sno, FILE *fd, const char *name, const char *io_mode, Term file_name, encoding_t encoding,
+                    stream_flags_t flags, void *vfs) {
   StreamDesc *st = &GLOBAL_Stream[sno];
-  st->status = flags;
+  if (io_mode == NULL)
+    Yap_Error(PERMISSION_ERROR_NEW_ALIAS_FOR_STREAM, MkIntegerTerm(sno), "File opened with NULL Permissions");
+    if (strchr(io_mode, 'a')) {
+        st->status = Append_Stream_f|Output_Stream_f|flags;
+    } else
+    if (strchr(io_mode, 'w')) {
+        st->status = Output_Stream_f | flags;
+    }
+    if (strchr(io_mode, 'r')) {
+        st->status = Input_Stream_f|flags;
+    }
+    if (strchr(io_mode, 'b')) {
+        st->status = Binary_Stream_f|flags;
+    }
 
   st->vfs = vfs;
   st->buf.on = false;
@@ -1150,12 +1154,13 @@ bool Yap_initStream(int sno, FILE *fd, const char *name, Term file_name,
   }
 
   if (name == NULL) {
-    char buf[YAP_FILENAME_MAX + 1];
-    memset(buf, 0, YAP_FILENAME_MAX + 1);
-    name = Yap_guessFileName(fd, sno, buf, YAP_FILENAME_MAX);
-    if (name)
-      st->name = Yap_LookupAtom(name);
+      char buf[YAP_FILENAME_MAX + 1];
+      memset(buf, 0, YAP_FILENAME_MAX + 1);
+      name = Yap_guessFileName(fd, sno, buf, YAP_FILENAME_MAX);
   }
+    if (!name)
+        Yap_Error(SYSTEM_ERROR_INTERNAL,file_name,"Yap_guessFileName failed: opening a file without a name");
+      st->name = Yap_LookupAtom(name);
   st->user_name = file_name;
   st->file = fd;
   st->linepos = 0;
@@ -1221,7 +1226,7 @@ static const param_t open_defs[] = {OPEN_DEFS()};
 
 static Int
 do_open(Term file_name, Term t2,
-        Term tlist USES_REGS) { /* '$open'(+File,+Mode,?Stream,-ReturnCode) */
+          Term tlist USES_REGS) {
   Atom open_mode;
   int sno;
   StreamDesc *st;
@@ -1232,6 +1237,7 @@ do_open(Term file_name, Term t2,
   encoding_t encoding;
   Term tenc;
   char io_mode[8];
+
   // original file name
   if (IsVarTerm(file_name)) {
     Yap_Error(INSTANTIATION_ERROR, file_name, "open/3");
@@ -1287,6 +1293,7 @@ do_open(Term file_name, Term t2,
                  ? args[OPEN_EXPAND_FILENAME].tvalue == TermTrue
                  : false) ||
             trueGlobalPrologFlag(OPEN_EXPANDS_FILENAME_FLAG);
+
   // expand file name?
   int lvl = push_text_stack();
   const char *fname = Yap_AbsoluteFile(fname0, ok);
@@ -1298,9 +1305,18 @@ do_open(Term file_name, Term t2,
 
   // Skip scripts that start with !#/.. or similar
   pop_text_stack(lvl);
-  bool script =
-      (args[OPEN_SCRIPT].used ? args[OPEN_SCRIPT].tvalue == TermTrue : false);
-  // binary type
+  
+  if (open_mode == AtomRead) {
+    strncpy(io_mode, "r", 8);
+  } else if (open_mode == AtomWrite) {
+    strncpy(io_mode, "w", 8);
+  } else if (open_mode == AtomAppend) {
+    strncpy(io_mode, "a", 8);
+  } else {
+    pop_text_stack(lvl);
+    return false;
+  }
+   // binary type
   if (args[OPEN_TYPE].used) {
     Term t = args[OPEN_TYPE].tvalue;
     bool bin = (t == TermBinary);
@@ -1323,39 +1339,37 @@ do_open(Term file_name, Term t2,
                 "type is ~a, must be one of binary or text", t);
     }
   }
-  // BOM mess
-  if (encoding == ENC_UTF16_BE || encoding == ENC_UTF16_LE ||
-      encoding == ENC_UCS2_BE || encoding == ENC_UCS2_LE ||
-      encoding == ENC_ISO_UTF32_BE || encoding == ENC_ISO_UTF32_LE) {
-    needs_bom = true;
-  }
-  if (args[OPEN_BOM].used) {
-    if (args[OPEN_BOM].tvalue == TermTrue) {
-      avoid_bom = false;
-      needs_bom = true;
-    } else if (args[OPEN_BOM].tvalue == TermFalse) {
-      avoid_bom = true;
-      needs_bom = false;
-    }
-  }
-  if (open_mode == AtomRead) {
-    strncpy(io_mode, "r", 8);
-  } else if (open_mode == AtomWrite) {
-    strncpy(io_mode, "w", 8);
-  } else if (open_mode == AtomAppend) {
-    strncpy(io_mode, "a", 8);
-  } else {
-    pop_text_stack(lvl);
-    return false;
-  }
-  if ((sno = Yap_OpenStream(fname, io_mode, file_name)) < 0) {
+   if ((sno = Yap_OpenStream(fname, io_mode, file_name, encoding)) < 0)
+  {
     pop_text_stack(lvl);
     return false;
   }
 
   st = &GLOBAL_Stream[sno];
-  st->user_name = file_name;
   // user requested encoding?
+  // BOM mess
+  if (encoding == ENC_UTF16_BE || encoding == ENC_UTF16_LE ||
+      encoding == ENC_UCS2_BE || encoding == ENC_UCS2_LE ||
+      encoding == ENC_ISO_UTF32_BE || encoding == ENC_ISO_UTF32_LE)
+  {
+    needs_bom = true;
+  }
+  if (args[OPEN_BOM].used)
+  {
+    if (args[OPEN_BOM].tvalue == TermTrue)
+    {
+      avoid_bom = false;
+      needs_bom = true;
+    }
+    else if (args[OPEN_BOM].tvalue == TermFalse)
+    {
+      avoid_bom = true;
+      needs_bom = false;
+    }
+  }
+  bool script =
+      (args[OPEN_SCRIPT].used ? args[OPEN_SCRIPT].tvalue == TermTrue : false);
+
   if (args[OPEN_ALIAS].used) {
     Atom al = AtomOfTerm(args[OPEN_ALIAS].tvalue);
     if (!Yap_AddAlias(al, sno)) {
@@ -1363,7 +1377,6 @@ do_open(Term file_name, Term t2,
       return false;
     }
   }
-  st->name = Yap_LookupAtom(fname);
   if (st - GLOBAL_Stream < 3) {
     flags |= RepError_Prolog_f;
   }
@@ -1557,14 +1570,13 @@ static Int p_open_null_stream(USES_REGS1) {
   return (Yap_unify(ARG1, t));
 }
 
-int Yap_OpenStream(const char *fname, const char *io_mode, Term user_name) {
+int Yap_OpenStream(const char *fname, const char* io_mode, Term user_name, encoding_t enc) {
   CACHE_REGS
   int sno;
   StreamDesc *st;
-  Atom at;
-  struct vfs *vfsp;
-  FILE *fd;
-  int flags;
+  struct vfs *vfsp = NULL;
+  FILE *fd = NULL;
+  int flags;                                                                                               
 
   sno = GetFreeStreamD();
   if (sno < 0) {
@@ -1573,20 +1585,20 @@ int Yap_OpenStream(const char *fname, const char *io_mode, Term user_name) {
     return -1;
   }
   st = GLOBAL_Stream + sno;
-  // read, write, append
-  st->file = NULL;
-  st->status = 0;
-  // fname = Yap_VF(fname);
+   // fname = Yap_VF(fname);
+  flags = 0;
   if ((vfsp = vfs_owner(fname)) != NULL) {
-    if (!vfsp->open(vfsp, sno, fname, "r")) {
+    if (!vfsp->open(vfsp, fname, io_mode, sno)) {
       UNLOCK(st->streamlock);
       PlIOError(EXISTENCE_ERROR_SOURCE_SINK, MkAtomTerm(Yap_LookupAtom(fname)),
                 "%s", fname);
+      /* extract BACK info passed through the stream descriptor */
       return -1;
     }
-    vfsp = GLOBAL_Stream[sno].vfs;
+    // read, write, append
+    user_name = st->user_name;
   } else {
-    fd = st->file = fopen(fname, io_mode);
+    fd  = fopen(fname, io_mode);
     if (fd == NULL) {
       if (!strchr(io_mode, 'b') && binary_file(fname)) {
         UNLOCK(st->streamlock);
@@ -1603,25 +1615,7 @@ int Yap_OpenStream(const char *fname, const char *io_mode, Term user_name) {
       return -1;
     }
   }
-  flags = st->status;
-  if (strchr(io_mode, 'w')) {
-    if (strchr(io_mode, 'a')) {
-      at = AtomAppend;
-      flags |= Append_Stream_f | Output_Stream_f;
-    } else {
-      at = AtomWrite;
-      flags |= Output_Stream_f;
-    }
-  }
-  if (strchr(io_mode, 'r')) {
-    at = AtomRead;
-    flags |= Input_Stream_f;
-  }
-  if (strchr(io_mode, 'b')) {
-    flags |= Binary_Stream_f;
-  }
-  Yap_initStream(sno, st->file, fname, user_name, LOCAL_encoding, flags, at,
-                 vfsp);
+    Yap_initStream(sno, fd, fname, io_mode, user_name, LOCAL_encoding, flags, vfsp);
   __android_log_print(ANDROID_LOG_INFO, "YAPDroid", "exists %s <%d>", fname,
                       sno);
   return sno;
@@ -1631,7 +1625,7 @@ int Yap_FileStream(FILE *fd, char *name, Term file_name, int flags,
                    VFS_t *vfsp) {
   CACHE_REGS
   int sno;
-  Atom at;
+  const char *mode;
 
   sno = GetFreeStreamD();
   if (sno < 0)
@@ -1639,12 +1633,13 @@ int Yap_FileStream(FILE *fd, char *name, Term file_name, int flags,
                       "new stream not available for opening"));
   if (flags & Output_Stream_f) {
     if (flags & Append_Stream_f)
-      at = AtomAppend;
+      mode = "a";
     else
-      at = AtomWrite;
-  } else
-    at = AtomRead;
-  Yap_initStream(sno, fd, name, file_name, LOCAL_encoding, flags, at, vfsp);
+      mode = "w";
+  } else {
+    mode = "r";
+  }
+    Yap_initStream(sno, fd, name, mode, file_name, LOCAL_encoding, flags, vfsp);
   return sno;
 }
 
diff --git a/os/iopreds.h b/os/iopreds.h
index e0b118251..e4eb1d476 100644
--- a/os/iopreds.h
+++ b/os/iopreds.h
@@ -31,9 +31,8 @@ INLINE_ONLY EXTERN inline bool IsStreamTerm(Term t) {
           (IsApplTerm(t) && (FunctorOfTerm(t) == FunctorStream)));
 }
 
-extern bool Yap_initStream(int sno, FILE *fd, const char *name, Term file_name,
-                           encoding_t encoding, stream_flags_t flags,
-                           Atom open_mode, void *vfs);
+extern bool Yap_initStream(int sno, FILE *fd, const char *name, const char *io_mode, Term file_name, encoding_t encoding,
+                           stream_flags_t flags, void *vfs);
 
 #define Yap_CheckStream(arg, kind, msg)                                        \
   Yap_CheckStream__(__FILE__, __FUNCTION__, __LINE__, arg, kind, msg)
diff --git a/os/mem.c b/os/mem.c
index 322b6a270..066874601 100644
--- a/os/mem.c
+++ b/os/mem.c
@@ -193,7 +193,7 @@ bool Yap_set_stream_to_buf(StreamDesc *st, const char *buf,
   st->file = f = NULL;
   flags = Input_Stream_f | InMemory_Stream_f;
   st->vfs = NULL;
-  Yap_initStream(st - GLOBAL_Stream, f, NULL, TermNil, LOCAL_encoding, flags,
+  Yap_initStream(st - GLOBAL_Stream, f, "r", TermNil, LOCAL_encoding, flags,
                  AtomRead, NULL);
   // like any file stream.
   /* currently these streams are not seekable */
@@ -228,7 +228,7 @@ int Yap_open_buf_read_stream(const char *buf, size_t nchars, encoding_t *encp,
   st->file = f = NULL;
   flags = Input_Stream_f | InMemory_Stream_f;
   st->vfs = NULL;
-  Yap_initStream(sno, f, NULL, TermNil, encoding, flags, AtomRead, NULL);
+  Yap_initStream(sno, f, ""wa", TermNil, encoding, flags, AtomRead, NULL);
   // like any file stream.
   /* currently these streams are not seekable */
   st->status = Input_Stream_f | InMemory_Stream_f;
diff --git a/os/sig.c b/os/sig.c
index 99ceae5f1..efd2ee8e1 100644
--- a/os/sig.c
+++ b/os/sig.c
@@ -860,5 +860,6 @@ void Yap_InitSignalPreds(void) {
   Yap_InitCPred("virtual_alarm", 4, virtual_alarm, SafePredFlag | SyncPredFlag);
   Yap_InitCPred("enable_interrupts", 0, enable_interrupts, SafePredFlag);
   Yap_InitCPred("disable_interrupts", 0, disable_interrupts, SafePredFlag);
+  my_signal_info(SIGSEGV, HandleSIGSEGV);
   CurrentModule = cm;
 }
diff --git a/os/streams.c b/os/streams.c
index 27dfcc81a..d3ff1f91d 100644
--- a/os/streams.c
+++ b/os/streams.c
@@ -445,19 +445,19 @@ found_eof(int sno,
 
 static bool
 stream_mode(int sno,
-            Term t2 USES_REGS) { /* '$set_output'(+Stream,-ErrorMessage)  */
-  stream_flags_t flags = GLOBAL_Stream[sno].status &
-                         (Input_Stream_f | Output_Stream_f | Append_Stream_f);
+            Term t2 USES_REGS) {
+  /* '$set_output'(+Stream,-ErrorMessage)  */
+  stream_flags_t flags = GLOBAL_Stream[sno].status;
   if (!IsVarTerm(t2) && !(isatom(t2))) {
-    return FALSE;
+    return false;
   }
   if (flags & Input_Stream_f)
     return Yap_unify(t2, TermRead);
-  if (flags & Output_Stream_f)
-    return Yap_unify(t2, TermWrite);
   if (flags & Append_Stream_f)
-    return Yap_unify(t2, TermAppend);
-  return false;
+    return Yap_unify(t2, TermWrite);
+ if (flags & Output_Stream_f)
+    return Yap_unify(t2, TermWrite);
+   return false;
 }
 
 static bool
diff --git a/os/yapio.h b/os/yapio.h
index 3bc389397..656f65c4b 100644
--- a/os/yapio.h
+++ b/os/yapio.h
@@ -86,7 +86,7 @@ extern int Yap_PlGetWchar(void);
 extern int Yap_PlFGetchar(void);
 extern int Yap_GetCharForSIGINT(void);
 extern Int Yap_StreamToFileNo(Term);
-extern int Yap_OpenStream(const char*, const char*, Term);
+extern int Yap_OpenStream(const char *fname, const char* io_mode, Term user_name, encoding_t enc);
 extern int Yap_FileStream(FILE*, char *, Term, int, VFS_t *);
 extern char *Yap_TermToBuffer(Term t, encoding_t encoding, int flags);
 extern char *Yap_HandleToString(yhandle_t l, size_t sz, size_t *length,
diff --git a/os/yio.yap b/os/yio.yap
index bd1e1a037..b37757a95 100644
--- a/os/yio.yap
+++ b/os/yio.yap
@@ -350,7 +350,6 @@ with  _S_.
 
 */
 current_stream(File, Mode, Stream) :-
-
     stream_property(Stream, mode(Mode)),
     '$stream_name'(Stream, File).
 
diff --git a/packages/python/pl2pl.c b/packages/python/pl2pl.c
index 82acbfda7..b9661f772 100644
--- a/packages/python/pl2pl.c
+++ b/packages/python/pl2pl.c
@@ -119,17 +119,17 @@ static foreign_t prolog_list_to_python_list(term_t plist, term_t pyt, term_t tle
   term_t targ = PL_new_term_ref();
 
   if (PL_skip_list(plist, targ, &sz) <0 || ! PL_get_nil(targ)) {
-    pyErrorAndReturn( false, false);
+    pyErrorAndReturn( false);
 }
   if (!PyList_Check(pyl))
     {
-      pyErrorAndReturn( false, false);
+      pyErrorAndReturn( false);
     }
   if (sz > PyList_GET_SIZE(pyl))
-    pyErrorAndReturn( false, false);
+    pyErrorAndReturn( false);
   for  (i=0; i < sz; i++) {
     if (!PL_get_list(plist, targ, plist)) {
-      pyErrorAndReturn( false, false);
+      pyErrorAndReturn( false);
     }
     PyObject *t = term_to_python(targ, true, NULL, true);
     PyList_SET_ITEM(pyl, i, t);
@@ -139,7 +139,7 @@ static foreign_t prolog_list_to_python_list(term_t plist, term_t pyt, term_t tle
 } else {
 python_assign(tlen, PyLong_FromUnsignedLong(sz), NULL);
 }
-  pyErrorAndReturn( true, false);
+  pyErrorAndReturn( true);
 }
 
 install_t install_pl2pl(void) {
diff --git a/packages/python/py2pl.c b/packages/python/py2pl.c
index a52a5edeb..5af802c76 100644
--- a/packages/python/py2pl.c
+++ b/packages/python/py2pl.c
@@ -207,6 +207,7 @@ foreign_t python_to_term(PyObject *pVal, term_t t) {
 }
 
 X_API YAP_Term pythonToYAP(PyObject *pVal) {
+
   term_t t = PL_new_term_ref();
   if (pVal == NULL || !python_to_term(pVal, t)) {
     PL_reset_term_refs(t);
diff --git a/packages/python/py4yap.h b/packages/python/py4yap.h
index aaaa5d2fe..0c799427e 100644
--- a/packages/python/py4yap.h
+++ b/packages/python/py4yap.h
@@ -168,14 +168,12 @@ extern void pyErrorHandler__(int line, const char *file, const char *code);
     }                                                                          \
   }
 
-#define pyErrorAndReturn(x, y)                                                 \
+#define pyErrorAndReturn(x)                                                    \
   {                                                                            \
     if (PyErr_Occurred()) {                                                    \
       pyErrorHandler__(__LINE__, __FILE__, __FUNCTION__);                      \
-      return (x);                                                              \
-    } else {                                                                   \
-      return (x);                                                              \
     }                                                                          \
+    return (x);                                                                \
   }
 // #define pyErrorAndReturn( x, y ) return x
 
diff --git a/packages/python/pyio.c b/packages/python/pyio.c
index 0c645922d..4fdc5586f 100644
--- a/packages/python/pyio.c
+++ b/packages/python/pyio.c
@@ -43,7 +43,7 @@ static int py_put(int sno, int ch)
 }
 
 VFS_t pystream;
- static void *py_open(VFS_t *me, int sno, const char *name, const char *io_mode) {
+ static void *py_open(VFS_t *me, const char *name, const char *io_mode, int sno) {
 #if HAVE_STRCASESTR
   if (strcasestr(name, "/python/") == name)
     name += strlen("/python/");
@@ -51,29 +51,28 @@ VFS_t pystream;
   if (strstr(name, "/python/") == name)
     name += strlen("/python/");
 #endif
+    PyObject *pystream = string_to_python(name, true, NULL);
+    if (pystream == NULL || pystream == Py_None) {
+      return NULL;
+    } 
   StreamDesc *st = YAP_RepStreamFromId(sno);
-  if  (strcmp(name,"sys.output") == 0) {
+  st->name = YAP_LookupAtom(name);
+  if  (0&&strcmp(name,"sys.stdout") == 0) {
     st->user_name = TermOutStream;
-  } else if(strcmp(name,"sys.error") == 0) {
+  } else if(0&&strcmp(name,"sys.stderr") == 0) {
     st->user_name = TermErrStream;
   } else {
-    // we assume object is already open, so there is no need to open it.
-    PyObject *pystream = string_to_python(name, true, NULL);
-    if (pystream == Py_None) {
-      return NULL;
-    } else  {
-      st->u.private_data = pystream;
-      st->vfs = me;
-      st->name = YAP_LookupAtom(name);
-      st->user_name = YAP_MkAtomTerm(st->name);
-    }
+    st->user_name = YAP_MkAtomTerm(st->name);
   }
+  // we assume object is already open, so there is no need to open it.
+  st->u.private_data = pystream;
+  st->vfs = me;
   return st;
 }
 
 static bool py_close(int sno) {
-    StreamDesc *st = YAP_RepStreamFromId(sno);
-  Py_DECREF(st->u.private_data);
+  StreamDesc *st = YAP_RepStreamFromId(sno);
+  Py_XDECREF(st->u.private_data);
   return true;
 }
 
@@ -153,7 +152,7 @@ return PyLong_AsLong(pyr);
 
 static void py_flush(int sno) {
   StreamDesc *s = YAP_GetStreamFromId(sno);
-  YAP_Term tg =   python_acquire_GIL();
+  PyGILState_STATE  tg =   python_acquire_GIL();
   PyObject *flush = PyObject_GetAttrString(s->u.private_data, "flush");
   PyObject_CallFunction(flush, NULL);
     python_release_GIL(tg);
diff --git a/packages/python/pypreds.c b/packages/python/pypreds.c
index c95896c2d..d3c15276f 100644
--- a/packages/python/pypreds.c
+++ b/packages/python/pypreds.c
@@ -14,10 +14,10 @@ static foreign_t python_len(term_t tobj, term_t tf) {
 
   o = term_to_python(tobj, true, NULL, true);
   if (o == NULL) {
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
   len = PyObject_Length(o);
-  pyErrorAndReturn(PL_unify_int64(tf, len), false);
+  pyErrorAndReturn(PL_unify_int64(tf), false);
 }
 
 static foreign_t python_dir(term_t tobj, term_t tf) {
@@ -26,13 +26,13 @@ static foreign_t python_dir(term_t tobj, term_t tf) {
 
   o = term_to_python(tobj, true, NULL, true);
   if (o == NULL) {
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
   dir = PyObject_Dir(o);
   {
     foreign_t rc = address_to_term(dir, tf);
     ;
-    pyErrorAndReturn(rc, false);
+    pyErrorAndReturn(rc);
   }
 }
 
@@ -43,14 +43,14 @@ static foreign_t python_index(term_t tobj, term_t tindex, term_t val) {
 
   o = term_to_python(tobj, true, NULL, true);
   if (o == NULL) {
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
   if (!PySequence_Check(o)) {
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
   i = term_to_python(tindex, true, NULL, true);
   if (i == NULL) {
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
 #if PY_MAJOR_VERSION < 3
   f = PyObject_CallMethodObjArgs(o, PyString_FromString("getitem"), i);
@@ -60,7 +60,7 @@ static foreign_t python_index(term_t tobj, term_t tindex, term_t val) {
   {
     foreign_t rc = address_to_term(f, val);
     ;
-    pyErrorAndReturn(rc, false);
+    pyErrorAndReturn(rc);
   }
 }
 
@@ -72,13 +72,13 @@ static foreign_t python_is(term_t tobj, term_t tf) {
   o = term_to_python(tobj, true, NULL, true);
   if (!o) {
     python_release_GIL(lim);
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
   foreign_t rc = python_to_term(o, tf);
   if (rc)
     PyErr_Clear();
   python_release_GIL(lim);
-  pyErrorAndReturn(rc, false);
+  pyErrorAndReturn(rc);
 }
 
 static foreign_t python_proc(term_t tobj) {
@@ -89,7 +89,7 @@ static foreign_t python_proc(term_t tobj) {
   o = term_to_python(tobj, true, NULL, true);
   python_release_GIL(lim);
   bool rc = o != NULL;
-  pyErrorAndReturn(rc, false);
+  pyErrorAndReturn(rc);
 }
 
 static foreign_t python_slice(term_t parent, term_t indx, term_t tobj) {
@@ -104,10 +104,10 @@ static foreign_t python_slice(term_t parent, term_t indx, term_t tobj) {
   p = term_to_python(parent, true, NULL, true);
   // Exp
   if (!pI || !p) {
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   } else if ((pF = PySequence_GetSlice(p, 0, 0)) == NULL) {
     PyErr_Print();
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   }
   Py_DecRef(pI);
   Py_DecRef(p);
@@ -115,7 +115,7 @@ static foreign_t python_slice(term_t parent, term_t indx, term_t tobj) {
   {
     foreign_t rc;
     rc = address_to_term(pF, tobj);
-    pyErrorAndReturn(rc, false);
+    pyErrorAndReturn(rc);
   }
 }
 
@@ -132,14 +132,14 @@ static foreign_t python_apply(term_t tin, term_t targs, term_t keywds,
   pF = term_to_python(tin, true, NULL, true);
   PyErr_Clear();
   if (pF == NULL) {
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   }
   if (PL_is_atom(targs)) {
     pArgs = NULL;
   } else {
 
     if (!PL_get_name_arity(targs, &aname, &arity)) {
-      { pyErrorAndReturn(false, false); }
+      { pyErrorAndReturn(false); }
     }
     if (arity == 1 && PL_get_arg(1, targs, targ) && PL_is_variable(targ)) {
       /* ignore (_) */
@@ -150,16 +150,16 @@ static foreign_t python_apply(term_t tin, term_t targs, term_t keywds,
       DebugPrintf("Tuple %p\n", pArgs);
 
       if (!pArgs) {
-        pyErrorAndReturn(false, false);
+        pyErrorAndReturn(false);
       }
       for (i = 0; i < arity; i++) {
         PyObject *pArg;
         if (!PL_get_arg(i + 1, targs, targ)) {
-          pyErrorAndReturn(false, false);
+          pyErrorAndReturn(false);
         }
         pArg = term_to_python(targ, true, NULL, true);
         if (pArg == NULL) {
-          pyErrorAndReturn(false, false);
+          pyErrorAndReturn(false);
         }
         /* pArg reference stolen here: */
         PyTuple_SetItem(pArgs, i, pArg);
@@ -188,16 +188,16 @@ static foreign_t python_apply(term_t tin, term_t targs, term_t keywds,
     }
   } else {
     PyErr_Print();
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   }
   if (pArgs)
     Py_DECREF(pArgs);
   Py_DECREF(pF);
   if (pValue == NULL) {
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
   out = address_to_term(pValue, tf);
-  pyErrorAndReturn(out, false);
+  pyErrorAndReturn(out);
 }
 
 static foreign_t assign_python(term_t exp, term_t name) {
@@ -206,11 +206,11 @@ static foreign_t assign_python(term_t exp, term_t name) {
 
   if (e == NULL) {
     python_release_GIL(stackp);
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
   bool b = python_assign(name, e, NULL);
   python_release_GIL(stackp);
-  pyErrorAndReturn(b, false);
+  pyErrorAndReturn(b);
 }
 
 static foreign_t python_builtin_eval(term_t caller, term_t dict, term_t out) {
@@ -224,27 +224,27 @@ static foreign_t python_builtin_eval(term_t caller, term_t dict, term_t out) {
 
   if ((env = py_Builtin) == NULL) {
     // no point in  even trying
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   }
   if (PL_get_name_arity(caller, &name, &arity)) {
     if (!(s = PL_atom_chars(name))) {
-      pyErrorAndReturn(false, false);
+      pyErrorAndReturn(false);
     }
     if ((pI = PyObject_GetAttrString(env, s)) == NULL) {
       PyErr_Print();
-      { pyErrorAndReturn(false, false); }
+      { pyErrorAndReturn(false); }
     }
     Py_INCREF(pI);
   } else {
     // Prolog should make sure this never happens.
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   }
   pArgs = PyTuple_New(arity);
   DebugPrintf("Tuple %p\n", pArgs);
   for (i = 0; i < arity; i++) {
     PyObject *pArg;
     if (!PL_get_arg(i + 1, caller, targ)) {
-      pyErrorAndReturn(false, false);
+      pyErrorAndReturn(false);
     }
     /* ignore (_) */
     if (i == 0 && PL_is_variable(targ)) {
@@ -252,13 +252,13 @@ static foreign_t python_builtin_eval(term_t caller, term_t dict, term_t out) {
     } else {
       pArg = term_to_python(targ, true, NULL, true);
       if (pArg == NULL) {
-        pyErrorAndReturn(false, false);
+        pyErrorAndReturn(false);
       }
     }
     /* pArg reference stolen here: */
     if (PyTuple_SetItem(pArgs, i, pArg)) {
       PyErr_Print();
-      { pyErrorAndReturn(false, false); }
+      { pyErrorAndReturn(false); }
     }
   }
   pOut = PyObject_CallObject(pI, pArgs);
@@ -266,12 +266,12 @@ static foreign_t python_builtin_eval(term_t caller, term_t dict, term_t out) {
   Py_DECREF(pI);
   if (pOut == NULL) {
     PyErr_Print();
-   { pyErrorAndReturn(false, false); }
+   { pyErrorAndReturn(false); }
   }
   {
     foreign_t rc = address_to_term(pOut, out);
     ;
-    pyErrorAndReturn(rc, false);
+    pyErrorAndReturn(rc);
   }
 }
 
@@ -284,37 +284,37 @@ static foreign_t python_access(term_t obj, term_t f, term_t out) {
   term_t targ = PL_new_term_ref();
 
   if (o == NULL) {
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
   if (PL_is_atom(f)) {
     if (!PL_get_atom_chars(f, &s)) {
-      pyErrorAndReturn(false, false);
+      pyErrorAndReturn(false);
     }
     if ((pValue = PyObject_GetAttrString(o, s)) == NULL) {
       PyErr_Print();
-      { pyErrorAndReturn(false, false); }
+      { pyErrorAndReturn(false); }
     }
     Py_INCREF(pValue);
-    { pyErrorAndReturn(python_to_term(pValue, out), false); }
+    { pyErrorAndReturn(python_to_term(pValue), false); }
   }
   if (!PL_get_name_arity(f, &name, &arity)) {
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   }
   s = PL_atom_chars(name);
   if (!s) {
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
   if ((pF = PyObject_GetAttrString(o, s)) == NULL) {
-    DebugPrintf("Function %p\n", pArgs);
+    DebugPrintf("Function %p\n", o);
     PyErr_Print();
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   }
   pArgs = PyTuple_New(arity);
   DebugPrintf("Tuple %p\n", pArgs);
   for (i = 0; i < arity; i++) {
     PyObject *pArg;
     if (!PL_get_arg(i + 1, f, targ)) {
-      pyErrorAndReturn(false, false);
+      pyErrorAndReturn(false);
     }
     /* ignore (_) */
     if (i == 0 && PL_is_variable(targ)) {
@@ -322,7 +322,7 @@ static foreign_t python_access(term_t obj, term_t f, term_t out) {
     }
     pArg = term_to_python(targ, true, NULL, true);
     if (pArg == NULL) {
-      pyErrorAndReturn(false, false);
+      pyErrorAndReturn(false);
     }
     /* pArg reference stolen here: */
     PyTuple_SetItem(pArgs, i, pArg);
@@ -331,9 +331,9 @@ static foreign_t python_access(term_t obj, term_t f, term_t out) {
   Py_DECREF(pArgs);
   Py_DECREF(pF);
   if (pValue == NULL) {
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   }
-  { pyErrorAndReturn(python_to_term(pValue, out), false); }
+  { pyErrorAndReturn(python_to_term(pValue), false); }
 }
 
 static foreign_t python_field(term_t parent, term_t att, term_t tobj) {
@@ -343,7 +343,7 @@ static foreign_t python_field(term_t parent, term_t att, term_t tobj) {
   int arity;
 
   if (!PL_get_name_arity(att, &name, &arity)) {
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   } else {
     PyObject *p;
 
@@ -352,29 +352,29 @@ static foreign_t python_field(term_t parent, term_t att, term_t tobj) {
     p = term_to_python(parent, true, NULL, true);
     // Exp
     if (!PL_get_name_arity(att, &name, &arity)) {
-      { pyErrorAndReturn(false, false); }
+      { pyErrorAndReturn(false); }
     }
     s = PL_atom_chars(name);
     if (arity == 1 && !strcmp(s, "()")) {
       if (!PL_get_arg(1, att, att)) {
-        pyErrorAndReturn(false, false);
+        pyErrorAndReturn(false);
       }
       if (!PL_get_name_arity(att, &name, &arity)) {
-        { pyErrorAndReturn(false, false); }
+        { pyErrorAndReturn(false); }
       }
       s = PL_atom_chars(name);
     }
     if (!s || !p) {
-      { pyErrorAndReturn(false, false); }
+      { pyErrorAndReturn(false); }
     } else if ((pF = PyObject_GetAttrString(p, s)) == NULL) {
       PyErr_Clear();
-      { pyErrorAndReturn(false, false); }
+      { pyErrorAndReturn(false); }
     }
   }
   {
     foreign_t rc;
     rc = address_to_term(pF, tobj);
-    pyErrorAndReturn(rc, false);
+    pyErrorAndReturn(rc);
   }
 }
 
@@ -383,7 +383,7 @@ static foreign_t python_main_module(term_t mod) {
     foreign_t rc;
     PyErr_Clear();
     rc = address_to_term(py_Main, mod);
-    pyErrorAndReturn(rc, false);
+    pyErrorAndReturn(rc);
   }
 }
 
@@ -392,7 +392,7 @@ static foreign_t python_function(term_t tobj) {
   PyObject *obj = term_to_python(tobj, true, NULL, true);
   foreign_t rc = PyFunction_Check(obj);
 
-  pyErrorAndReturn(rc, false);
+  pyErrorAndReturn(rc);
 }
 
 foreign_t python_builtin(term_t out) {
@@ -400,7 +400,7 @@ foreign_t python_builtin(term_t out) {
     foreign_t rc;
     PyErr_Clear();
     rc = address_to_term(py_Builtin, out);
-    pyErrorAndReturn(rc, false);
+    pyErrorAndReturn(rc);
   }
 }
 
@@ -417,15 +417,15 @@ static foreign_t python_run_file(term_t file) {
 #else
     FILE *f = fopen(s, "r");
     if (f == NULL) {
-      pyErrorAndReturn(false, false);
+      pyErrorAndReturn(false);
     }
     PyRun_SimpleFileEx(f, s, 1);
 #endif
     {
-      { pyErrorAndReturn(true, false); }
+      { pyErrorAndReturn(true); }
     }
   }
-  { pyErrorAndReturn(false, false); }
+  { pyErrorAndReturn(false); }
 }
 
 extern PyThreadState *YAP_save;
@@ -442,7 +442,7 @@ static foreign_t python_run_command(term_t cmd) {
     PyRun_SimpleString(s);
     rc = true;
   }
-  pyErrorAndReturn(rc, false);
+  pyErrorAndReturn(rc);
 }
 
 static foreign_t python_run_script(term_t cmd, term_t fun) {
@@ -483,7 +483,7 @@ static foreign_t python_run_script(term_t cmd, term_t fun) {
           Py_DECREF(pModule);
           PyErr_Print();
           fprintf(stderr, "Call failed\n");
-          { pyErrorAndReturn(false, false); }
+          { pyErrorAndReturn(false); }
         }
       } else {
         pyErrorHandler();
@@ -495,11 +495,11 @@ static foreign_t python_run_script(term_t cmd, term_t fun) {
       Py_DECREF(pModule);
     } else {
       PyErr_Print();
-      { pyErrorAndReturn(false, false); }
+      { pyErrorAndReturn(false); }
     }
-    { pyErrorAndReturn(true, false); }
+    { pyErrorAndReturn(true); }
   }
-  { pyErrorAndReturn(false, false); }
+  { pyErrorAndReturn(false); }
 }
 
 static foreign_t python_export(term_t t, term_t pl) {
@@ -510,16 +510,16 @@ static foreign_t python_export(term_t t, term_t pl) {
     term_t targ = PL_new_term_ref();
 
     if (!PL_get_arg(1, t, targ)) {
-      pyErrorAndReturn(false, false);
+      pyErrorAndReturn(false);
     }
     if (!PL_get_pointer(targ, &ptr)) {
-      pyErrorAndReturn(false, false);
+      pyErrorAndReturn(false);
     }
     Py_INCREF((PyObject *)ptr);
-    /* pyErrorAndReturn( __main__, false) */
+    /* pyErrorAndReturn( __main__) */
     rc = python_to_term((PyObject *)ptr, pl);
   }
-  pyErrorAndReturn(rc, false);
+  pyErrorAndReturn(rc);
 }
 
 /**
@@ -546,7 +546,7 @@ static int python_import(term_t mname, term_t mod) {
       if (!PL_get_arg(1, mname, arg) || !PL_get_atom_chars(arg, &sa) ||
           !PL_get_arg(2, mname, mname)) {
         python_release_GIL(t0);
-        pyErrorAndReturn(false, false);
+        pyErrorAndReturn(false);
       }
       PL_get_atom_chars(arg, &sa);
       strcpy(s, sa);
@@ -556,7 +556,7 @@ static int python_import(term_t mname, term_t mod) {
     } else if (!PL_get_nchars(mname, &len, &s,
                               CVT_ATOM | CVT_EXCEPTION | REP_UTF8)) {
       python_release_GIL(t0);
-      pyErrorAndReturn(false, false);
+      pyErrorAndReturn(false);
     } else {
       break;
     }
@@ -568,7 +568,7 @@ static int python_import(term_t mname, term_t mod) {
 #endif
   python_release_GIL(t0);
   if (pName == NULL) {
-    pyErrorAndReturn(false, false);
+    pyErrorAndReturn(false);
   }
 
   PyObject *pModule = PyImport_Import(pName);
@@ -580,11 +580,11 @@ static int python_import(term_t mname, term_t mod) {
       PyErr_Print();
     PyErr_Clear();
 #endif
-    { pyErrorAndReturn(false, false); }
+    { pyErrorAndReturn(false); }
   }
   {
     foreign_t rc = address_to_term(pModule, mod);
-    pyErrorAndReturn(rc, false);
+    pyErrorAndReturn(rc);
   }
 }
 
@@ -593,8 +593,8 @@ static foreign_t python_to_rhs(term_t inp, term_t t) {
   PyErr_Clear();
   pVal = term_to_python(inp, true, NULL, true);
   if (pVal == NULL)
-    pyErrorAndReturn(false, false);
-  pyErrorAndReturn(address_to_term(pVal, t), false);
+    pyErrorAndReturn(false);
+  pyErrorAndReturn(address_to_term(pVal), false);
 }
 
 // static PyThreadState *_saveP = NULL;
@@ -605,7 +605,7 @@ static YAP_Int
   p_python_ensure(term_t ptr)
   {
      PyGILState_STATE _tState = PyGILState_Ensure();
-     pyErrorAndReturn( PL_unify_int64(ptr, _tState), false);
+     pyErrorAndReturn( PL_unify_int64(ptr), false);
   }
 
 static YAP_Int
@@ -615,7 +615,7 @@ static YAP_Int
     PyGILState_STATE _tState;
     PL_get_int64( ptr, &_tState);
     PyGILState_Release( _tState );
-  pyErrorAndReturn( true, false);
+  pyErrorAndReturn( true);
   }
 */
 
@@ -628,40 +628,50 @@ static YAP_Int p_python_threaded(void) {
   // PyEval_ReleaseThread(tstate);
   // _threaded = true;
   //    _locked = 0;
-  pyErrorAndReturn(true, false);
+  pyErrorAndReturn(true);
 }
 
+static PyGILState_STATE gstates[64];
+static int gstatei = 0;
 
 term_t python_acquire_GIL(void) {
 static PyGILState_STATE gstate;
   term_t curSlot = PL_new_term_ref();
-  if (!_threaded)
-    pyErrorAndReturn(curSlot, false);
   //   extern int Yap_do_low_level_trace;
   // Yap_do_low_level_trace = 1;
-  // f[rintf( stderr, "++%d\n", ++_locked);
+  // fprintf( stderr, "++%d\n", ++_locked);
   //  if (_locked > 0) { _locked++  ; }
   // else
-  gstate = PyGILState_Ensure();
-  fprintf(stderr, "+%d\n", (int)gstate);
-  PL_put_integer(curSlot, gstate);
-  pyErrorAndReturn(curSlot, false);
+  if (_threaded) {
+    gstates[gstatei] = PyGILState_Ensure();
+  }
+  fprintf(stderr, "+%d\n", (int)gstatei);
+  PL_put_integer(curSlot, gstatei++);
+  return curSlot;
 }
 
 bool python_release_GIL(term_t curBlock) {
  PyGILState_STATE gstate;
+ int gstateix;
 
-  if (_threaded) {
-    PL_get_integer(curBlock, &gstate);
-    PyGILState_Release(gstate);
-    fprintf(stderr, "-%d\n", (int)gstate);
+    PL_get_integer(curBlock, &gstateix);
+    PL_reset_term_refs(curBlock);
+    if (gstatei != gstateix) {
+      if (gstateix > gstatei) {
+	fprintf(stderr, "gstateix(%d) > gstatei(%d)\n", gstateix, gstatei);
+	return false;
+      } else {
+	fprintf(stderr, "gstateix(%d) < gstatei(%d)\n", gstateix, gstatei);
+  return false;
+      }
+    }
+    if (_threaded) {
+    PyGILState_Release(gstates[gstatei--]);
   }
-  PL_reset_term_refs(curBlock);
-  pyErrorAndReturn(true, false);
+  pyErrorAndReturn(true);
 }
 
-//: prolog: release python
-
+/
 install_t install_pypreds(void) {
   PL_register_foreign("python_builtin_eval", 3, python_builtin_eval, 0);
   PL_register_foreign("python_builtin", 1, python_builtin, 0);
diff --git a/packages/python/swig/yap4py/yapi.py b/packages/python/swig/yap4py/yapi.py
index 6542105f8..25d4853da 100644
--- a/packages/python/swig/yap4py/yapi.py
+++ b/packages/python/swig/yap4py/yapi.py
@@ -1,12 +1,21 @@
-
-import os.path
-import sys
-import keyword
-# debugging support.
-# import pdb
-from collections import namedtuple
 import readline
-from .yap import *
+from yap4py.yap import YAPEngine, YAPEngineArgs, YAPPredicate, YAPQuery, YAPPrologPredicate, YAPVarTerm
+from os.path import join, dirname
+from collections import namedtuple
+import sys
+
+yap_lib_path = dirname(__file__)
+
+compile = namedtuple('compile', 'file')
+bindvars = namedtuple('bindvars', 'list')
+library = namedtuple('library', 'list')
+v0 = namedtuple('v', 'slot')
+yap_query = namedtuple('yap_query', 'query owner')
+jupyter_query = namedtuple('jupyter_query', 'vars dict')
+python_query = namedtuple('python_query', 'vars dict')
+yapi_query = namedtuple('yapi_query', 'vars dict')
+show_answer = namedtuple('show_answer', 'vars dict')
+set_prolog_flag = namedtuple('set_prolog_flag', 'flag new_value')
 
 
 class Engine( YAPEngine ):
@@ -16,10 +25,10 @@ class Engine( YAPEngine ):
         if not args:
             args = EngineArgs(**kwargs)
         if self_contained:
-            yap_lib_path = os.path.dirname(__file__)
-            args.setYapShareDir(os.path.join(yap_lib_path, "prolog"))
+            yap_lib_path = dirname(__file__)
+            args.setYapShareDir(join(yap_lib_path, "prolog"))
             args.setYapPLDIR(yap_lib_path)
-            args.setSavedState(os.path.join(yap_lib_path, "startup.yss"))
+            args.setSavedState(join(yap_lib_path, "startup.yss"))
         YAPEngine.__init__(self, args)
         self.goal(set_prolog_flag('verbose', 'silent'))
         self.goal(compile(library('yapi')))
@@ -31,9 +40,6 @@ class Engine( YAPEngine ):
         else:
             self.goal(g)
 
-    def f(self, g):
-        self.E.fun(g)
-
 
 class EngineArgs( YAPEngineArgs ):
     """ Interface to Engine Options class"""
@@ -47,112 +53,79 @@ class Predicate( YAPPredicate ):
     def __init__(self, t, module=None):
         super().__init__(t)
 
-class IQuery(YAPQuery):
+class Query:
     """Goal is a predicate instantiated under a specific environment """
     def __init__(self, engine, g):
-        self = engine.query(g)
-        self.port = "call"
-        self.bindings = None
+        self.q = engine.query(g)
+        if self.q:
+            self.port = "call"
+            self.bindings = None
+            self.engine = engine
+            self.answer = {}
 
     def __iter__(self):
-        return PrologTableIter( self )
-
-class PrologTableIter:
-
-    def __init__(self, q):
-        try:
-            self.q = q
-        except:
-            print('Error')
-
-    def __iter__(self):
-        # Iterators are iterables too.
-        # -        # Adding this functions to make them so.
         return self
 
     def __next__(self):
+        print(self)
         if not self.q:
             raise StopIteration()
         if self.q.next():
-            rc = self.q.bindings
-            if self.q.port == "exit":
-                self.q.close()
+            rc = self.answer
+            if self.port == "exit":
+                self.close()
             return rc
         else:
-            if self.q:
+            if self:
                 self.close()
             raise StopIteration()
 
-    def close(self):
+    def close( self ):
         self.q.close()
         self.q = None
 
-f2p = {"fails":{}}
-for i in range(16):
-    f2p[i] ={}
 
-
-
-
-global engine, handler
-
-yap_lib_path = os.path.dirname(__file__)
-
-compile = namedtuple('compile', 'file')
-bindvars = namedtuple('bindvars', 'list')
-library = namedtuple('library', 'list')
-v = namedtuple( 'v', 'slot')
-yap_query = namedtuple( 'yap_query', 'query owner')
-jupyter_query = namedtuple( 'jupyter_query', 'vars dict')
-python_query = namedtuple( 'python_query', 'vars dict')
-yapi_query = namedtuple( 'yapi_query', 'vars dict')
-show_answer = namedtuple( 'show_answer', 'vars dict')
-set_prolog_flag = namedtuple('set_prolog_flag', 'flag new_value')
-
-
-def named( name, arity):
+def name( name, arity):
     try:
-        if  arity > 0 and name.isidentifier() and not keyword.iskeyword(name):
+        if  arity > 0 and name.isidentifier(): # and not keyword.iskeyword(name):
             s = []
             for i in range(arity):
                 s += ["A" + str(i)]
-            f2p[arity][name] = namedtuple(name, s)
+            return namedtuple(name, s)
     except:
-        f2p[fails][name] = True
+        return None
 
 class PrologPredicate( YAPPrologPredicate ):
     """ Interface to Prolog  Predicate"""
 
-class v(YAPVarTerm):
+class v(YAPVarTerm,v0):
     def __init__(self):
-        super().__init__()
+        YAPVarTerm.__init__()
 
     def binding(self):
         return self.term()
 
-def numbervars(  q ):
-    Dict = {}
-    if True:
-        engine.goal(show_answer( q.namedVars(), Dict))
-        return Dict
-    rc = q.namedVarsVector()
-    q.r = q.goal().numbervars()
-    o = []
-    for i  in rc:
-        if len(i) == 2:
-            do = str(i[0]) + " = " + str( i[1] ) + "\n"
-            o += do
-        else:
-            do = str(i[0]) + " = " + str( i[1] ) + "\n"
-            o += do
-    return o
 
 class YAPShell:
 
+    def numbervars( self ):
+        Dict = {}
+        self.engine.goal(show_answer( self, Dict))
+        return Dict
+        # rc = self.q.namedVarsVector()
+        # self.q.r = self.q.goal().numbervars()
+        # o = []
+        # for i  in rc:
+        #     if len(i) == 2:
+        #         do = str(i[0]) + " = " + str( i[1] ) + "\n"
+        #         o += do
+        #     else:
+        #         do = str(i[0]) + " = " + str( i[1] ) + "\n"
+        #         o += do
+        # return o
 
 
-
-    def query_prolog(self, engine, query):
+    def query_prolog(self, query):
         #import pdb; pdb.set_trace()
         #
         # construct a query from a one-line string
@@ -172,12 +145,12 @@ class YAPShell:
         #        print( "Error: Variable Name matches a Python Symbol")
         #        return
         do_ask = True
-        self.e = engine
+        engine = self.engine
         bindings = []
         g = python_query(self, query)
         if not self.q:
-            self.it = IQuery( engine, g )
-        for bind in self.it:
+            self.q = Query( engine, g )
+        for bind in self.q:
             bindings += [bind]
             if do_ask:
                 print(bindings)
@@ -214,7 +187,7 @@ class YAPShell:
                 if not s:
                     loop = False
                 else:
-                    self.query_prolog(engine, s)
+                    self.query_prolog(s)
             except SyntaxError as err:
                 print("Syntax Error error: {0}".format(err))
             except EOFError:
@@ -233,13 +206,13 @@ class YAPShell:
     # engine = yap.YAPEngine(yap.YAPParams());
     #
     def __init__(self, engine, **kwargs):
-       self.live(engine)
+        self.engine = engine
+        self.live(engine)
 
 
 
 def main():
     engine = Engine()
-    handler = numbervars
     YAPShell(engine)
 
 if __name__ == "__main__":
diff --git a/packages/python/yap_kernel/yap_ipython/core/interactiveshell.py b/packages/python/yap_kernel/yap_ipython/core/interactiveshell.py
index a0231ebd5..bcf280720 100644
--- a/packages/python/yap_kernel/yap_ipython/core/interactiveshell.py
+++ b/packages/python/yap_kernel/yap_ipython/core/interactiveshell.py
@@ -2664,9 +2664,22 @@ class InteractiveShell(SingletonConfigurable):
         print("go")
         result = None
         try:
-            result = self._yrun_cell(
-                       raw_cell, store_history, silent, shell_futures)
+            import trace
+            tracer = trace.Trace(
+                #ignoredirs=[sys.prefix, sys.exec_prefix],
+                trace=1,
+                count=0)
+
+            # run the new command using the given tracer
+            #
+            result =tracer.runfunc(self._yrun_cell,
+                                   raw_cell, store_history,
+                                   silent, shell_futures)
+
+        #     result = self._yrun_cell(
+        #                raw_cell, store_history, silent, shell_futures)
         finally:
+            print("ugh", self.events)
             self.events.trigger('post_execute')
             if not silent:
                 self.events.trigger('post_run_cell', result)
diff --git a/packages/python/yap_kernel/yap_ipython/prolog/jupyter.yap b/packages/python/yap_kernel/yap_ipython/prolog/jupyter.yap
index bcd6a9040..bf26c388d 100644
--- a/packages/python/yap_kernel/yap_ipython/prolog/jupyter.yap
+++ b/packages/python/yap_kernel/yap_ipython/prolog/jupyter.yap
@@ -62,9 +62,11 @@ blankc('\t').
 
 
 streams(false) :-
-%    close( user_input),
-    close( user_error ),
-    close( user_output ).
+	flush_output,
+	forall(
+	       stream_property( S, mode(_) ),
+	       close(S)
+	      ).
 streams(true) :-
 %	open('/python/input', read, _Input, [alias(user_input),bom(false)]),
 	open('/python/sys.stdout', append, _Output, [alias(user_output)]),
diff --git a/packages/python/yap_kernel/yap_ipython/yapi.py b/packages/python/yap_kernel/yap_ipython/yapi.py
index 5f07d0c76..73f78d015 100644
--- a/packages/python/yap_kernel/yap_ipython/yapi.py
+++ b/packages/python/yap_kernel/yap_ipython/yapi.py
@@ -39,6 +39,7 @@ completions = namedtuple('completions', 'txt self' )
 errors = namedtuple('errors', 'self text' )
 streams = namedtuple('streams', ' text' )
 
+global  engine
 
 class YAPInputSplitter(InputSplitter):
     """An input splitter that recognizes all of iyap's special syntax."""
@@ -106,11 +107,10 @@ class YAPInputSplitter(InputSplitter):
     def validQuery(self, text, engine, shell, line=None):
         """Return whether a legal query
         """
-        if text == shell.os:
+        if shell and text == shell.os:
             return True
         if not  line:
             line = text.rstrip()
-            (line, _, _, _)=self.shell.clean_end(line)
         self.errors = []
         engine.mgoal(errors(self, line),"user")
         return self.errors != []
@@ -181,7 +181,7 @@ class YAPInputSplitter(InputSplitter):
         if self.transformer_accumulating:
             return True
         else:
-            return self.validQuery(self.source, self.yapeng, self)
+            return self.validQuery(self.source, engine, self.shell)
 
     def transform_cell(self, cell):
         """Process and translate a cell of input.
@@ -509,6 +509,8 @@ class YAPRun:
     def __init__(self, shell):
         self.shell = shell
         self.yapeng = Engine()
+        global engine
+        engine = self.yapeng
         self.yapeng.goal(use_module(library("jupyter")))
         self.query = None
         self.os = None
@@ -542,6 +544,7 @@ class YAPRun:
                 pg = jupyter_query( self, program, query)
                 self.query =  self.yapeng.query(  pg)
                 self.query.port = "call"
+                self.query.answer = {}
             else:
                 self.query.port   = "retry"
                 self.os = s
diff --git a/packages/swig/android/streamer.cpp b/packages/swig/android/streamer.cpp
index ce99d8773..514d1d5f0 100644
--- a/packages/swig/android/streamer.cpp
+++ b/packages/swig/android/streamer.cpp
@@ -36,7 +36,7 @@ void Java_pt_up_yap_streamerJNI_swig_1module_1init__(void) {
 static std::string buff0;
 
 static void *
-and_open(struct vfs *me, int sno, const char *name, const char *io_mode) {
+and_open(struct vfs *me, const char *name, const char *io_mode, int sno) {
     // we assume object is already open, so there is no need to open it.
     GLOBAL_Stream[sno].vfs_handle = streamerInstance;
     GLOBAL_Stream[sno].vfs = me;
diff --git a/pl/absf.yap b/pl/absf.yap
index f8ae4311b..eab63a0fe 100755
--- a/pl/absf.yap
+++ b/pl/absf.yap
@@ -226,7 +226,7 @@ absolute_file_name(File0,File) :-
 '$find_in_path'(user_output,_,user_ouput, _, _) :- !.
 '$find_in_path'(user_error,_,user_error, _, _) :- !.
 '$find_in_path'(Name, Opts, File, _, First) :-
-%    (	atom(Name) -> true ; start_low_level_trace ),
+    %    (	atom(Name) -> true ; start_low_level_trace ),
 	get_abs_file_parameter( file_type, Opts, Type ),
     get_abs_file_parameter( access, Opts, Access ),
     get_abs_file_parameter( expand, Opts, Expand ),
diff --git a/pl/boot.yap b/pl/boot.yap
index 94d4b7fbc..d386872e3 100644
--- a/pl/boot.yap
+++ b/pl/boot.yap
@@ -250,9 +250,12 @@ initialize_prolog :-
 :- c_compile( 'preds.yap' ).
 :- c_compile( 'modules.yap' ).
 :- c_compile( 'grammar.yap' ).
+
+:- start_low_level_trace.
+
 :- ['absf.yap'].
 
-%:- start_low_level_trace.
+:- stop_low_level_trace.
 
 :- use_module('error.yap').
 
@@ -305,6 +308,8 @@ initialize_prolog :-
 
 :-	 ['protect.yap'].
 
+:- stop_low_level_trace.
+
 version(yap,[6,3]).
 
 :- op(1150,fx,(mode)).
@@ -444,7 +449,7 @@ modules defining clauses for it too.
 
 
 Dynamic predicate, normally not defined. Called by the Prolog system on run-time exceptions that can be repaired `just-in-time`. The values for  _Exception_ are described below. See also catch/3 and throw/1.
-If this hook predicate succeeds it must instantiate the  _Action_ argument to the atom `fail` to make the operation fail silently, `retry` to tell Prolog to retry the operation or `error` to make the system generate an exception. The action `retry` only makes sense if this hook modified the environment such that the operation can now succeed without error.
+If this hook preodicate succeeds it must instantiate the  _Action_ argument to the atom `fail` to make the operation fail silently, `retry` to tell Prolog to retry the operation or `error` to make the system generate an exception. The action `retry` only makes sense if this hook modified the environment such that the operation can now succeed without error.
 
 + `undefined_predicate`
  _Context_ is instantiated to a predicate-indicator ( _Module:Name/Arity_). If the predicate fails Prolog will generate an existence_error exception. The hook is intended to implement alternatives to the SWI built-in autoloader, such as autoloading code from a database. Do not use this hook to suppress existence errors on predicates. See also `unknown`.
diff --git a/regression/modules/goal_expansion_tests.yap b/regression/modules/goal_expansion_tests.yap
index 02ac2e6f1..86a00c8b9 100644
--- a/regression/modules/goal_expansion_tests.yap
+++ b/regression/modules/goal_expansion_tests.yap
@@ -1,4 +1,4 @@
-
+                               
 :- use_module(library(lists)).
 
 
@@ -13,4 +13,3 @@ given  user:goal_expansion(a(X,Y), m, Y is X*X ))
 
 test  m:a(3,X) returns X =@= 9
 given  user:goal_expansion(a(X,Y), m, Y is X*X ), user:goal_expansion(a(X), X is 3*5)
-