diff --git a/lauxlib.c b/lauxlib.c
index 22c9de35..777b1aaf 100644
--- a/lauxlib.c
+++ b/lauxlib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lauxlib.c,v 1.227 2010/11/10 18:05:36 roberto Exp roberto $
+** $Id: lauxlib.c,v 1.228 2011/01/10 15:51:42 roberto Exp roberto $
 ** Auxiliary functions for building Lua libraries
 ** See Copyright Notice in lua.h
 */
@@ -203,6 +203,64 @@ LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
   return lua_error(L);
 }
 
+
+LUALIB_API int luaL_fileresult (lua_State *L, int stat, const char *fname) {
+  int en = errno;  /* calls to Lua API may change this value */
+  if (stat) {
+    lua_pushboolean(L, 1);
+    return 1;
+  }
+  else {
+    lua_pushnil(L);
+    if (fname)
+      lua_pushfstring(L, "%s: %s", fname, strerror(en));
+    else
+      lua_pushfstring(L, "%s", strerror(en));
+    lua_pushinteger(L, en);
+    return 3;
+  }
+}
+
+
+#if !defined(inspectstat)	/* { */
+
+#if defined(LUA_USE_POSIX)
+
+#include <sys/wait.h>
+
+/*
+** use appropriate macros to interpret 'pclose' return status
+*/
+#define inspectstat(stat,what)  \
+   if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \
+   else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; }
+
+#else
+
+#define inspectstat(stat,what)  /* no op */
+
+#endif
+
+#endif				/* } */
+
+
+LUALIB_API int luaL_execresult (lua_State *L, int stat) {
+  const char *what = "exit";  /* type of termination */
+  if (stat == -1)  /* error? */
+    return luaL_fileresult(L, 0, NULL);
+  else {
+    inspectstat(stat, what);  /* interpret result */
+    if (*what == 'e' && stat == 0)  /* successful termination? */
+      return luaL_fileresult(L, 1, NULL);
+    else {  /* return nil,what,code */
+      lua_pushnil(L);
+      lua_pushstring(L, what);
+      lua_pushinteger(L, stat);
+      return 3;
+    }
+  }
+}
+
 /* }====================================================== */
 
 
diff --git a/lauxlib.h b/lauxlib.h
index 0c8f0f28..3123ef25 100644
--- a/lauxlib.h
+++ b/lauxlib.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lauxlib.h,v 1.113 2010/11/16 19:20:01 roberto Exp roberto $
+** $Id: lauxlib.h,v 1.114 2011/01/10 15:51:42 roberto Exp roberto $
 ** Auxiliary functions for building Lua libraries
 ** See Copyright Notice in lua.h
 */
@@ -62,6 +62,9 @@ LUALIB_API int (luaL_error) (lua_State *L, const char *fmt, ...);
 LUALIB_API int (luaL_checkoption) (lua_State *L, int narg, const char *def,
                                    const char *const lst[]);
 
+LUALIB_API int (luaL_fileresult) (lua_State *L, int stat, const char *fname);
+LUALIB_API int (luaL_execresult) (lua_State *L, int stat);
+
 /* pre-defined references */
 #define LUA_NOREF       (-2)
 #define LUA_REFNIL      (-1)
diff --git a/liolib.c b/liolib.c
index 85a4e0b2..a688ad93 100644
--- a/liolib.c
+++ b/liolib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: liolib.c,v 2.97 2011/02/10 15:35:50 roberto Exp roberto $
+** $Id: liolib.c,v 2.98 2011/02/21 19:12:54 roberto Exp roberto $
 ** Standard I/O (and system) library
 ** See Copyright Notice in lua.h
 */
@@ -33,20 +33,6 @@
 #define lua_popen(L,c,m)	((void)L, fflush(NULL), popen(c,m))
 #define lua_pclose(L,file)	((void)L, pclose(file))
 
-
-#if defined(LUA_USE_POSIX)	/* { */
-
-#include <sys/wait.h>
-
-/*
-** use appropriate macros to interpret 'pclose' return status
-*/
-#define inspectstat(stat,what)  \
-   if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \
-   else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; }
-
-#endif				/* } */
-
 #elif defined(LUA_WIN)		/* }{ */
 
 #define lua_popen(L,c,m)		((void)L, _popen(c,m))
@@ -64,10 +50,6 @@
 
 #endif			/* } */
 
-#if !defined(inspectstat)
-#define inspectstat(stat,what)	/* no op */
-#endif
-
 
 #define IO_INPUT	1
 #define IO_OUTPUT	2
@@ -76,24 +58,6 @@
 static const char *const fnames[] = {"input", "output"};
 
 
-static int pushresult (lua_State *L, int i, const char *filename) {
-  int en = errno;  /* calls to Lua API may change this value */
-  if (i) {
-    lua_pushboolean(L, 1);
-    return 1;
-  }
-  else {
-    lua_pushnil(L);
-    if (filename)
-      lua_pushfstring(L, "%s: %s", filename, strerror(en));
-    else
-      lua_pushfstring(L, "%s", strerror(en));
-    lua_pushinteger(L, en);
-    return 3;
-  }
-}
-
-
 static void fileerror (lua_State *L, int arg, const char *filename) {
   lua_pushfstring(L, "%s: %s", filename, strerror(errno));
   luaL_argerror(L, arg, lua_tostring(L, -1));
@@ -162,21 +126,8 @@ static int io_noclose (lua_State *L) {
 static int io_pclose (lua_State *L) {
   FILE **p = tofilep(L);
   int stat = lua_pclose(L, *p);
-  const char *what = "exit";  /* type of termination */
   *p = NULL;  /* mark stream as closed (for GC) */
-  if (stat == -1)  /* error? */
-    return pushresult(L, 0, NULL);
-  else {
-    inspectstat(stat, what);  /* interpret result from 'pclose' */
-    if (*what == 'e' && stat == 0)  /* successful termination? */
-      return pushresult(L, 1, NULL);
-    else {  /* return nil,what,code */
-      lua_pushnil(L);
-      lua_pushstring(L, what);
-      lua_pushinteger(L, stat);
-      return 3;
-    }
-  }
+  return luaL_execresult(L, stat);
 }
 
 
@@ -187,7 +138,7 @@ static int io_fclose (lua_State *L) {
   FILE **p = tofilep(L);
   int ok = (fclose(*p) == 0);
   *p = NULL;  /* mark stream as closed (for GC) */
-  return pushresult(L, ok, NULL);
+  return luaL_fileresult(L, ok, NULL);
 }
 
 
@@ -238,7 +189,7 @@ static int io_open (lua_State *L) {
                   " (should match " LUA_QL("[rwa]%%+?b?") ")", mode);
   pf = newfile(L);
   *pf = fopen(filename, mode);
-  return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+  return (*pf == NULL) ? luaL_fileresult(L, 0, filename) : 1;
 }
 
 
@@ -251,14 +202,14 @@ static int io_popen (lua_State *L) {
   const char *mode = luaL_optstring(L, 2, "r");
   FILE **pf = newfile(L);
   *pf = lua_popen(L, filename, mode);
-  return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+  return (*pf == NULL) ? luaL_fileresult(L, 0, filename) : 1;
 }
 
 
 static int io_tmpfile (lua_State *L) {
   FILE **pf = newfile(L);
   *pf = tmpfile();
-  return (*pf == NULL) ? pushresult(L, 0, NULL) : 1;
+  return (*pf == NULL) ? luaL_fileresult(L, 0, NULL) : 1;
 }
 
 
@@ -469,7 +420,7 @@ static int g_read (lua_State *L, FILE *f, int first) {
     }
   }
   if (ferror(f))
-    return pushresult(L, 0, NULL);
+    return luaL_fileresult(L, 0, NULL);
   if (!success) {
     lua_pop(L, 1);  /* remove last result */
     lua_pushnil(L);  /* push nil instead */
@@ -533,7 +484,7 @@ static int g_write (lua_State *L, FILE *f, int arg) {
     }
   }
   if (status) return 1;  /* file handle already on stack top */
-  else return pushresult(L, status, NULL);
+  else return luaL_fileresult(L, status, NULL);
 }
 
 
@@ -557,7 +508,7 @@ static int f_seek (lua_State *L) {
   long offset = luaL_optlong(L, 3, 0);
   op = fseek(f, offset, mode[op]);
   if (op)
-    return pushresult(L, 0, NULL);  /* error */
+    return luaL_fileresult(L, 0, NULL);  /* error */
   else {
     lua_pushinteger(L, ftell(f));
     return 1;
@@ -572,18 +523,18 @@ static int f_setvbuf (lua_State *L) {
   int op = luaL_checkoption(L, 2, NULL, modenames);
   lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE);
   int res = setvbuf(f, NULL, mode[op], sz);
-  return pushresult(L, res == 0, NULL);
+  return luaL_fileresult(L, res == 0, NULL);
 }
 
 
 
 static int io_flush (lua_State *L) {
-  return pushresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
+  return luaL_fileresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
 }
 
 
 static int f_flush (lua_State *L) {
-  return pushresult(L, fflush(tofile(L)) == 0, NULL);
+  return luaL_fileresult(L, fflush(tofile(L)) == 0, NULL);
 }
 
 
diff --git a/loslib.c b/loslib.c
index d4ec884c..fc7f5459 100644
--- a/loslib.c
+++ b/loslib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: loslib.c,v 1.32 2010/10/05 12:18:03 roberto Exp roberto $
+** $Id: loslib.c,v 1.33 2011/01/26 16:30:02 roberto Exp roberto $
 ** Standard Operating System library
 ** See Copyright Notice in lua.h
 */
@@ -59,37 +59,28 @@
 
 
 
-static int os_pushresult (lua_State *L, int i, const char *filename) {
-  int en = errno;  /* calls to Lua API may change this value */
-  if (i) {
-    lua_pushboolean(L, 1);
+static int os_execute (lua_State *L) {
+  const char *cmd = luaL_optstring(L, 1, NULL);
+  int stat = system(cmd);
+  if (cmd != NULL)
+    return luaL_execresult(L, stat);
+  else {
+    lua_pushboolean(L, stat);  /* true if there is a shell */
     return 1;
   }
-  else {
-    lua_pushnil(L);
-    lua_pushfstring(L, "%s: %s", filename, strerror(en));
-    lua_pushinteger(L, en);
-    return 3;
-  }
-}
-
-
-static int os_execute (lua_State *L) {
-  lua_pushinteger(L, system(luaL_optstring(L, 1, NULL)));
-  return 1;
 }
 
 
 static int os_remove (lua_State *L) {
   const char *filename = luaL_checkstring(L, 1);
-  return os_pushresult(L, remove(filename) == 0, filename);
+  return luaL_fileresult(L, remove(filename) == 0, filename);
 }
 
 
 static int os_rename (lua_State *L) {
   const char *fromname = luaL_checkstring(L, 1);
   const char *toname = luaL_checkstring(L, 2);
-  return os_pushresult(L, rename(fromname, toname) == 0, fromname);
+  return luaL_fileresult(L, rename(fromname, toname) == 0, fromname);
 }