entered into RCS

2 files changed, 181 insertions, 363 deletions

diff --git a/src/bytecode.c b/src/bytecode.c
index 5ab689f1925..f888a68b7f6 100644
--- a/src/bytecode.c
+++ b/src/bytecode.c
@@ -1,11 +1,11 @@
 /* Execution of byte code produced by bytecomp.el.
-   Copyright (C) 1985, 1986, 1987, 1988, 1992 Free Software Foundation, Inc.
+   Copyright (C) 1985, 1986, 1987, 1988 Free Software Foundation, Inc.
 
 This file is part of GNU Emacs.
 
 GNU Emacs is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
+the Free Software Foundation; either version 1, or (at your option)
 any later version.
 
 GNU Emacs is distributed in the hope that it will be useful,
@@ -17,12 +17,14 @@ You should have received a copy of the GNU General Public License
 along with GNU Emacs; see the file COPYING.  If not, write to
 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 
-hacked on by jwz@lucid.com 17-jun-91
+hacked on by jwz 17-jun-91
   o  added a compile-time switch to turn on simple sanity checking;
   o  put back the obsolete byte-codes for error-detection;
+  o  put back fset, symbol-function, and read-char because I don't
+     see any reason for them to have been removed;
   o  added a new instruction, unbind_all, which I will use for 
      tail-recursion elimination;
-  o  made temp_output_buffer_show be called with the right number
+  o  made temp_output_buffer_show() be called with the right number
      of args;
   o  made the new bytecodes be called with args in the right order;
   o  added metering support.
@@ -32,49 +34,48 @@ by Hallvard:
   o  all conditionals now only do QUIT if they jump.
  */
 
+
 #include "config.h"
 #include "lisp.h"
 #include "buffer.h"
 #include "syntax.h"
 
-/*
- * define BYTE_CODE_SAFE to enable some minor sanity checking (useful for 
- * debugging the byte compiler...)
- *
- * define BYTE_CODE_METER to enable generation of a byte-op usage histogram. 
+/* Define this to enable some minor sanity checking
+   (useful for debugging the byte compiler...)
+ */
+#define BYTE_CODE_SAFE
+
+/* Define this to enable generation of a histogram of byte-op usage.
  */
-/* #define BYTE_CODE_SAFE */
-/* #define BYTE_CODE_METER */
+#define BYTE_CODE_METER
 
 
 #ifdef BYTE_CODE_METER
 
-Lisp_Object Vbyte_code_meter, Qbyte_code_meter;
+Lisp_Object Vbyte_code_meter;
 int byte_metering_on;
 
-#define METER_2(code1, code2) \
+# define METER_2(code1,code2) \
   XFASTINT (XVECTOR (XVECTOR (Vbyte_code_meter)->contents[(code1)]) \
             ->contents[(code2)])
 
-#define METER_1(code) METER_2 (0, (code))
-
-#define METER_CODE(last_code, this_code)                        \
-{                                                               \
-  if (byte_metering_on)                                         \
-    {                                                           \
-      if (METER_1 (this_code) != ((1<<VALBITS)-1))              \
-        METER_1 (this_code)++;                                  \
-      if (last_code                                             \
-          && METER_2 (last_code, this_code) != ((1<<VALBITS)-1))        \
-        METER_2 (last_code, this_code)++;                       \
-    }                                                           \
-}
+# define METER_1(code) METER_2 (0,(code))
 
-#else /* no BYTE_CODE_METER */
+# define METER_CODE(last_code, this_code) {                     \
+  if (byte_metering_on) {                                       \
+     if (METER_1 (this_code) != ((1<<VALBITS)-1))               \
+        METER_1 (this_code) ++;                                 \
+     if (last_code &&                                           \
+        METER_2 (last_code,this_code) != ((1<<VALBITS)-1))      \
+        METER_2 (last_code,this_code) ++;                       \
+  }                                                             \
+ }
 
-#define METER_CODE(last_code, this_code)
+#else /* ! BYTE_CODE_METER */
 
-#endif /* no BYTE_CODE_METER */
+# define meter_code(last_code, this_code)
+
+#endif
 
 
 Lisp_Object Qbytecode;
@@ -146,7 +147,7 @@ Lisp_Object Qbytecode;
 #define Bbobp 0157
 #define Bcurrent_buffer 0160
 #define Bset_buffer 0161
-#define Bread_char 0162 /* No longer generated as of v19 */
+#define Bread_char 0162
 #define Bset_mark 0163 /* this loser is no longer generated as of v18 */
 #define Binteractive_p 0164 /* Needed since interactive-p takes unevalled args */
 
@@ -160,7 +161,6 @@ Lisp_Object Qbytecode;
 #define Bdelete_region 0174
 #define Bnarrow_to_region 0175
 #define Bwiden 0176
-#define Bend_of_line 0177
 
 #define Bconstant2 0201
 #define Bgoto 0202
@@ -184,12 +184,6 @@ Lisp_Object Qbytecode;
 
 #define Bunbind_all 0222
 
-#define Bset_marker 0223
-#define Bmatch_beginning 0224
-#define Bmatch_end 0225
-#define Bupcase 0226
-#define Bdowncase 0227
-
 #define Bstringeqlsign 0230
 #define Bstringlss 0231
 #define Bequal 0232
@@ -208,16 +202,6 @@ Lisp_Object Qbytecode;
 #define Bnumberp 0247
 #define Bintegerp 0250
 
-#define BRgoto 0252
-#define BRgotoifnil 0253
-#define BRgotoifnonnil 0254
-#define BRgotoifnilelsepop 0255
-#define BRgotoifnonnilelsepop 0256
-
-#define BlistN 0257
-#define BconcatN 0260
-#define BinsertN 0261
-
 #define Bconstant 0300
 #define CONSTANTLIM 0100
 
@@ -301,10 +285,11 @@ If the third argument is incorrect, Emacs may crash.")
     {
 #ifdef BYTE_CODE_SAFE
       if (stackp > stacke)
-        error ("Byte code stack overflow (byte compiler bug), pc %d, depth %d",
+        error (
+     "Stack overflow in byte code (byte compiler bug), pc = %d, depth = %d",
                pc - XSTRING (string_saved)->data, stacke - stackp);
       if (stackp < stack)
-        error ("Byte code stack underflow (byte compiler bug), pc %d",
+        error ("Stack underflow in byte code (byte compiler bug), pc = %d",
                pc - XSTRING (string_saved)->data);
 #endif
 
@@ -405,19 +390,7 @@ If the third argument is incorrect, Emacs may crash.")
         case Bcall+4: case Bcall+5:
           op -= Bcall;
         docall:
-          DISCARD (op);
-#ifdef BYTE_CODE_METER
-          if (byte_metering_on && XTYPE (TOP) == Lisp_Symbol)
-            {
-              v1 = TOP;
-              v2 = Fget (v1, Qbyte_code_meter);
-              if (XTYPE (v2) == Lisp_Int)
-                {
-                  XSETINT (v2, XINT (v2) + 1);
-                  Fput (v1, Qbyte_code_meter, v2);
-                }
-            }
-#endif
+          DISCARD(op);
           TOP = Ffuncall (op + 1, &TOP);
           break;
 
@@ -438,7 +411,8 @@ If the third argument is incorrect, Emacs may crash.")
 
         case Bunbind_all:
           /* To unbind back to the beginning of this frame.  Not used yet,
-             but will be needed for tail-recursion elimination.  */
+             but wil be needed for tail-recursion elimination.
+           */
           unbind_to (count, Qnil);
           break;
 
@@ -450,7 +424,7 @@ If the third argument is incorrect, Emacs may crash.")
 
         case Bgotoifnil:
           op = FETCH2;
-          if (NILP (POP))
+          if (NULL (POP))
             {
               QUIT;
               pc = XSTRING (string_saved)->data + op;
@@ -459,7 +433,7 @@ If the third argument is incorrect, Emacs may crash.")
 
         case Bgotoifnonnil:
           op = FETCH2;
-          if (!NILP (POP))
+          if (!NULL (POP))
             {
               QUIT;
               pc = XSTRING (string_saved)->data + op;
@@ -468,65 +442,22 @@ If the third argument is incorrect, Emacs may crash.")
 
         case Bgotoifnilelsepop:
           op = FETCH2;
-          if (NILP (TOP))
+          if (NULL (TOP))
             {
               QUIT;
               pc = XSTRING (string_saved)->data + op;
             }
-          else DISCARD (1);
+          else DISCARD(1);
           break;
 
         case Bgotoifnonnilelsepop:
           op = FETCH2;
-          if (!NILP (TOP))
+          if (!NULL (TOP))
             {
               QUIT;
               pc = XSTRING (string_saved)->data + op;
             }
-          else DISCARD (1);
-          break;
-
-        case BRgoto:
-          QUIT;
-          pc += *pc - 127;
-          break;
-
-        case BRgotoifnil:
-          if (NILP (POP))
-            {
-              QUIT;
-              pc += *pc - 128;
-            }
-          pc++;
-          break;
-
-        case BRgotoifnonnil:
-          if (!NILP (POP))
-            {
-              QUIT;
-              pc += *pc - 128;
-            }
-          pc++;
-          break;
-
-        case BRgotoifnilelsepop:
-          op = *pc++;
-          if (NILP (TOP))
-            {
-              QUIT;
-              pc += op - 128;
-            }
-          else DISCARD (1);
-          break;
-
-        case BRgotoifnonnilelsepop:
-          op = *pc++;
-          if (!NILP (TOP))
-            {
-              QUIT;
-              pc += op - 128;
-            }
-          else DISCARD (1);
+          else DISCARD(1);
           break;
 
         case Breturn:
@@ -534,7 +465,7 @@ If the third argument is incorrect, Emacs may crash.")
           goto exit;
 
         case Bdiscard:
-          DISCARD (1);
+          DISCARD(1);
           break;
 
         case Bdup:
@@ -598,7 +529,7 @@ If the third argument is incorrect, Emacs may crash.")
             {
               if (CONSP (v1))
                 v1 = XCONS (v1)->cdr;
-              else if (!NILP (v1))
+              else if (!NULL (v1))
                 {
                   immediate_quit = 0;
                   v1 = wrong_type_argument (Qlistp, v1);
@@ -622,7 +553,7 @@ If the third argument is incorrect, Emacs may crash.")
           break;
 
         case Blistp:
-          TOP = CONSP (TOP) || NILP (TOP) ? Qt : Qnil;
+          TOP = CONSP (TOP) || NULL (TOP) ? Qt : Qnil;
           break;
 
         case Beq:
@@ -636,21 +567,21 @@ If the third argument is incorrect, Emacs may crash.")
           break;
 
         case Bnot:
-          TOP = NILP (TOP) ? Qt : Qnil;
+          TOP = NULL (TOP) ? Qt : Qnil;
           break;
 
         case Bcar:
           v1 = TOP;
         docar:
           if (CONSP (v1)) TOP = XCONS (v1)->car;
-          else if (NILP (v1)) TOP = Qnil;
+          else if (NULL (v1)) TOP = Qnil;
           else Fcar (wrong_type_argument (Qlistp, v1));
           break;
 
         case Bcdr:
           v1 = TOP;
           if (CONSP (v1)) TOP = XCONS (v1)->cdr;
-          else if (NILP (v1)) TOP = Qnil;
+          else if (NULL (v1)) TOP = Qnil;
           else Fcdr (wrong_type_argument (Qlistp, v1));
           break;
 
@@ -669,21 +600,15 @@ If the third argument is incorrect, Emacs may crash.")
           break;
 
         case Blist3:
-          DISCARD (2);
+          DISCARD(2);
           TOP = Flist (3, &TOP);
           break;
 
         case Blist4:
-          DISCARD (3);
+          DISCARD(3);
           TOP = Flist (4, &TOP);
           break;
 
-        case BlistN:
-          op = FETCH;
-          DISCARD (op - 1);
-          TOP = Flist (op, &TOP);
-          break;
-
         case Blength:
           TOP = Flength (TOP);
           break;
@@ -727,26 +652,20 @@ If the third argument is incorrect, Emacs may crash.")
           break;
 
         case Bconcat2:
-          DISCARD (1);
+          DISCARD(1);
           TOP = Fconcat (2, &TOP);
           break;
 
         case Bconcat3:
-          DISCARD (2);
+          DISCARD(2);
           TOP = Fconcat (3, &TOP);
           break;
 
         case Bconcat4:
-          DISCARD (3);
+          DISCARD(3);
           TOP = Fconcat (4, &TOP);
           break;
 
-        case BconcatN:
-          op = FETCH;
-          DISCARD (op - 1);
-          TOP = Fconcat (op, &TOP);
-          break;
-
         case Bsub1:
           v1 = TOP;
           if (XTYPE (v1) == Lisp_Int)
@@ -797,7 +716,7 @@ If the third argument is incorrect, Emacs may crash.")
           break;
 
         case Bdiff:
-          DISCARD (1);
+          DISCARD(1);
           TOP = Fminus (2, &TOP);
           break;
 
@@ -813,32 +732,33 @@ If the third argument is incorrect, Emacs may crash.")
           break;
 
         case Bplus:
-          DISCARD (1);
+          DISCARD(1);
           TOP = Fplus (2, &TOP);
           break;
 
         case Bmax:
-          DISCARD (1);
+          DISCARD(1);
           TOP = Fmax (2, &TOP);
           break;
 
         case Bmin:
-          DISCARD (1);
+          DISCARD(1);
           TOP = Fmin (2, &TOP);
           break;
 
         case Bmult:
-          DISCARD (1);
+          DISCARD(1);
           TOP = Ftimes (2, &TOP);
           break;
 
         case Bquo:
-          DISCARD (1);
+          DISCARD(1);
           TOP = Fquo (2, &TOP);
           break;
 
         case Brem:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Frem (TOP, v1);
           break;
 
@@ -855,12 +775,6 @@ If the third argument is incorrect, Emacs may crash.")
           TOP = Finsert (1, &TOP);
           break;
 
-        case BinsertN:
-          op = FETCH;
-          DISCARD (op - 1);
-          TOP = Finsert (op, &TOP);
-          break;
-
         case Bpoint_max:
           XFASTINT (v1) = ZV;
           PUSH (v1);
@@ -928,24 +842,29 @@ If the third argument is incorrect, Emacs may crash.")
           break;
 
         case Bforward_char:
+          /* This was wrong!  --jwz */
           TOP = Fforward_char (TOP);
           break;
 
         case Bforward_word:
+          /* This was wrong!  --jwz */
           TOP = Fforward_word (TOP);
           break;
 
         case Bskip_chars_forward:
+          /* This was wrong!  --jwz */
           v1 = POP;
           TOP = Fskip_chars_forward (TOP, v1);
           break;
 
         case Bskip_chars_backward:
+          /* This was wrong!  --jwz */
           v1 = POP;
           TOP = Fskip_chars_backward (TOP, v1);
           break;
 
         case Bforward_line:
+          /* This was wrong!  --jwz */
           TOP = Fforward_line (TOP);
           break;
 
@@ -961,11 +880,13 @@ If the third argument is incorrect, Emacs may crash.")
 
         case Bdelete_region:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fdelete_region (TOP, v1);
           break;
 
         case Bnarrow_to_region:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fnarrow_to_region (TOP, v1);
           break;
 
@@ -973,49 +894,27 @@ If the third argument is incorrect, Emacs may crash.")
           PUSH (Fwiden ());
           break;
 
-        case Bend_of_line:
-          TOP = Fend_of_line (TOP);
-          break;
-
-        case Bset_marker:
-          v1 = POP;
-          v2 = POP;
-          TOP = Fset_marker (TOP, v2, v1);
-          break;
-
-        case Bmatch_beginning:
-          TOP = Fmatch_beginning (TOP);
-          break;
-
-        case Bmatch_end:
-          TOP = Fmatch_end (TOP);
-          break;
-
-        case Bupcase:
-          TOP = Fupcase (TOP);
-          break;
-
-        case Bdowncase:
-          TOP = Fdowncase (TOP);
-        break;
-
         case Bstringeqlsign:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fstring_equal (TOP, v1);
           break;
 
         case Bstringlss:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fstring_lessp (TOP, v1);
           break;
 
         case Bequal:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fequal (TOP, v1);
           break;
 
         case Bnthcdr:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fnthcdr (TOP, v1);
           break;
 
@@ -1033,11 +932,13 @@ If the third argument is incorrect, Emacs may crash.")
 
         case Bmember:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fmember (TOP, v1);
           break;
 
         case Bassq:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fassq (TOP, v1);
           break;
 
@@ -1047,11 +948,13 @@ If the third argument is incorrect, Emacs may crash.")
 
         case Bsetcar:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fsetcar (TOP, v1);
           break;
 
         case Bsetcdr:
           v1 = POP;
+          /* This had args in the wrong order.  -- jwz */
           TOP = Fsetcdr (TOP, v1);
           break;
 
@@ -1072,12 +975,13 @@ If the third argument is incorrect, Emacs may crash.")
           break;
 
         case Bnconc:
-          DISCARD (1);
+          DISCARD(1);
           TOP = Fnconc (2, &TOP);
           break;
 
         case Bnumberp:
-          TOP = (NUMBERP (TOP) ? Qt : Qnil);
+          TOP = (XTYPE (TOP) == Lisp_Int || XTYPE (TOP) == Lisp_Float
+                 ? Qt : Qnil);
           break;
 
         case Bintegerp:
@@ -1092,7 +996,7 @@ If the third argument is incorrect, Emacs may crash.")
           error ("scan-buffer is an obsolete bytecode");
           break;
         case Bmark:
-          error ("mark is an obsolete bytecode");
+          error("mark is an obsolete bytecode");
           break;
 #endif
 
@@ -1131,18 +1035,17 @@ syms_of_bytecode ()
 #ifdef BYTE_CODE_METER
 
   DEFVAR_LISP ("byte-code-meter", &Vbyte_code_meter,
-   "A vector of vectors which holds a histogram of byte-code usage.");
+   "a vector of vectors which holds a histogram of byte-code usage.");
   DEFVAR_BOOL ("byte-metering-on", &byte_metering_on, "");
 
   byte_metering_on = 0;
-  Vbyte_code_meter = Fmake_vector (make_number (256), make_number (0));
-  Qbyte_code_meter = intern ("byte-code-meter");
-  staticpro (&Qbyte_code_meter);
+  Vbyte_code_meter = Fmake_vector(make_number(256), make_number(0));
+
   {
     int i = 256;
     while (i--)
-      XVECTOR (Vbyte_code_meter)->contents[i] =
-        Fmake_vector (make_number (256), make_number (0));
+      XVECTOR(Vbyte_code_meter)->contents[i] =
+        Fmake_vector(make_number(256), make_number(0));
   }
 #endif
 }
diff --git a/src/callproc.c b/src/callproc.c
index 253d6877851..7d8185c5a4b 100644
--- a/src/callproc.c
+++ b/src/callproc.c
@@ -1,5 +1,5 @@
 /* Synchronous subprocess invocation for GNU Emacs.
-   Copyright (C) 1985, 1986, 1987, 1988, 1992 Free Software Foundation, Inc.
+   Copyright (C) 1985, 1986, 1987, 1988 Free Software Foundation, Inc.
 
 This file is part of GNU Emacs.
 
@@ -19,7 +19,6 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
 
 
 #include <signal.h>
-#include <errno.h>
 
 #include "config.h"
 
@@ -58,11 +57,16 @@ extern char **environ;
 
 #define max(a, b) ((a) > (b) ? (a) : (b))
 
-Lisp_Object Vexec_path, Vexec_directory, Vdata_directory;
+Lisp_Object Vexec_path, Vexec_directory;
 
 Lisp_Object Vshell_file_name;
 
+#ifndef MAINTAIN_ENVIRONMENT
+/* List of strings to append to front of environment of
+   all subprocesses when they are started.  */
+
 Lisp_Object Vprocess_environment;
+#endif
 
 /* True iff we are about to fork off a synchronous process or if we
    are waiting for it.  */
@@ -99,13 +103,13 @@ Fourth arg DISPLAY non-nil means redisplay buffer as output is inserted.\n\
 Remaining arguments are strings passed as command arguments to PROGRAM.\n\
 If BUFFER is nil or 0, returns immediately with value nil.\n\
 Otherwise waits for PROGRAM to terminate\n\
-and returns a numeric exit status or a signal description string.\n\
+and returns a numeric exit status or a signal name as a string.\n\
 If you quit, the process is killed with SIGKILL.")
   (nargs, args)
      int nargs;
      register Lisp_Object *args;
 {
-  Lisp_Object display, infile, buffer, path, current_dir;
+  Lisp_Object display, buffer, path;
   int fd[2];
   int filefd;
   register int pid;
@@ -117,37 +121,34 @@ If you quit, the process is killed with SIGKILL.")
 #if 0
   int mask;
 #endif
+  struct gcpro gcpro1;
+
+  GCPRO1 (*args);
+  gcpro1.nvars = nargs;
+
   CHECK_STRING (args[0], 0);
 
-  if (nargs >= 2 && ! NILP (args[1]))
-    {
-      infile = Fexpand_file_name (args[1], current_buffer->directory);
-      CHECK_STRING (infile, 1);
-    }
+  if (nargs <= 1 || NULL (args[1]))
+    args[1] = build_string ("/dev/null");
   else
-#ifdef VMS
-    infile = build_string ("NLA0:");
-#else
-    infile = build_string ("/dev/null");
-#endif /* not VMS */
+    args[1] = Fexpand_file_name (args[1], current_buffer->directory);
 
-  if (nargs >= 3)
-    {
-      register Lisp_Object tem;
-
-      buffer = tem = args[2];
-      if (!(EQ (tem, Qnil)
-            || EQ (tem, Qt)
-            || XFASTINT (tem) == 0))
-        {
-          buffer = Fget_buffer (tem);
-          CHECK_BUFFER (buffer, 2);
-        }
-    }
-  else 
-    buffer = Qnil;
+  CHECK_STRING (args[1], 1);
+
+  {
+    register Lisp_Object tem;
+    buffer = tem = args[2];
+    if (nargs <= 2)
+      buffer = Qnil;
+    else if (!(EQ (tem, Qnil) || EQ (tem, Qt)
+               || XFASTINT (tem) == 0))
+      {
+        buffer = Fget_buffer (tem);
+        CHECK_BUFFER (buffer, 2);
+      }
+  }
 
-  display = nargs >= 4 ? args[3] : Qnil;
+  display = nargs >= 3 ? args[3] : Qnil;
 
   {
     register int i;
@@ -161,14 +162,14 @@ If you quit, the process is killed with SIGKILL.")
     new_argv[i - 3] = 0;
   }
 
-  filefd = open (XSTRING (infile)->data, O_RDONLY, 0);
+  filefd = open (XSTRING (args[1])->data, O_RDONLY, 0);
   if (filefd < 0)
     {
-      report_file_error ("Opening process input file", Fcons (infile, Qnil));
+      report_file_error ("Opening process input file", Fcons (args[1], Qnil));
     }
   /* Search for program; barf if not found.  */
   openp (Vexec_path, args[0], "", &path, 1);
-  if (NILP (path))
+  if (NULL (path))
     {
       close (filefd);
       report_file_error ("Searching for program", Fcons (args[0], Qnil));
@@ -186,19 +187,19 @@ If you quit, the process is killed with SIGKILL.")
 #endif
     }
 
-  /* Make sure that the child will be able to chdir to the current
-     buffer's current directory.  We can't just have the child check
-     for an error when it does the chdir, since it's in a vfork.  */
-  current_dir = expand_and_dir_to_file (current_buffer->directory, Qnil);
-  if (NILP (Ffile_accessible_directory_p (current_dir)))
-    report_file_error ("Setting current directory",
-                       Fcons (current_buffer->directory, Qnil));
-
   {
     /* child_setup must clobber environ in systems with true vfork.
        Protect it from permanent change.  */
     register char **save_environ = environ;
     register int fd1 = fd[1];
+    char **env;
+
+#ifdef MAINTAIN_ENVIRONMENT
+    env = (char **) alloca (size_of_current_environ ());
+    get_current_environ (env);
+#else
+    env = environ;
+#endif /* MAINTAIN_ENVIRONMENT */
 
 #if 0  /* Some systems don't have sigblock.  */
     mask = sigblock (sigmask (SIGCHLD));
@@ -218,7 +219,7 @@ If you quit, the process is killed with SIGKILL.")
 #else
         setpgrp (pid, pid);
 #endif /* USG */
-        child_setup (filefd, fd1, fd1, new_argv, 0, current_dir);
+        child_setup (filefd, fd1, fd1, new_argv, env, 0);
       }
 
 #if 0
@@ -243,17 +244,13 @@ If you quit, the process is killed with SIGKILL.")
   if (XTYPE (buffer) == Lisp_Int)
     {
 #ifndef subprocesses
-      /* If Emacs has been built with asynchronous subprocess support,
-         we don't need to do this, I think because it will then have
-         the facilities for handling SIGCHLD.  */
       wait_without_blocking ();
 #endif /* subprocesses */
+
+      UNGCPRO;
       return Qnil;
     }
 
-  synch_process_death = 0;
-  synch_process_retcode = 0;
-
   record_unwind_protect (call_process_cleanup,
                          Fcons (make_number (fd[0]), make_number (pid)));
 
@@ -270,9 +267,9 @@ If you quit, the process is killed with SIGKILL.")
     while ((nread = read (fd[0], buf, sizeof buf)) > 0)
       {
         immediate_quit = 0;
-        if (!NILP (buffer))
+        if (!NULL (buffer))
           insert (buf, nread);
-        if (!NILP (display) && INTERACTIVE)
+        if (!NULL (display) && INTERACTIVE)
           redisplay_preserve_echo_area ();
         immediate_quit = 1;
         QUIT;
@@ -288,6 +285,8 @@ If you quit, the process is killed with SIGKILL.")
 
   unbind_to (count, Qnil);
 
+  UNGCPRO;
+
   if (synch_process_death)
     return build_string (synch_process_death);
   return make_number (synch_process_retcode);
@@ -311,7 +310,7 @@ Sixth arg DISPLAY non-nil means redisplay buffer as output is inserted.\n\
 Remaining args are passed to PROGRAM at startup as command args.\n\
 If BUFFER is nil, returns immediately with value nil.\n\
 Otherwise waits for PROGRAM to terminate\n\
-and returns a numeric exit status or a signal description string.\n\
+and returns a numeric exit status or a signal name as a string.\n\
 If you quit, the process is killed with SIGKILL.")
   (nargs, args)
      int nargs;
@@ -320,6 +319,10 @@ If you quit, the process is killed with SIGKILL.")
   register Lisp_Object filename_string, start, end;
   char tempfile[20];
   int count = specpdl_ptr - specpdl;
+  struct gcpro gcpro1;
+
+  GCPRO1 (*args);
+  gcpro1.nvars = 2;
 
 #ifdef VMS
   strcpy (tempfile, "tmp:emacsXXXXXX.");
@@ -334,12 +337,13 @@ If you quit, the process is killed with SIGKILL.")
   Fwrite_region (start, end, filename_string, Qnil, Qlambda);
   record_unwind_protect (delete_temp_file, filename_string);
 
-  if (!NILP (args[3]))
+  if (!NULL (args[3]))
     Fdelete_region (start, end);
 
   args[3] = filename_string;
   Fcall_process (nargs - 2, args + 2);
 
+  UNGCPRO;
   return unbind_to (count, Qnil);
 }
 
@@ -358,21 +362,14 @@ If you quit, the process is killed with SIGKILL.")
    ENV is the environment for the subprocess.
 
    SET_PGRP is nonzero if we should put the subprocess into a separate
-   process group.  
-
-   CURRENT_DIR is an elisp string giving the path of the current
-   directory the subprocess should have.  Since we can't really signal
-   a decent error from within the child, this should be verified as an
-   executable directory by the parent.  */
+   process group.  */
 
-child_setup (in, out, err, new_argv, set_pgrp, current_dir)
+child_setup (in, out, err, new_argv, env, set_pgrp)
      int in, out, err;
      register char **new_argv;
+     char **env;
      int set_pgrp;
-     Lisp_Object current_dir;
 {
-  char **env;
-
   register int pid = getpid();
 
   setpriority (PRIO_PROCESS, pid, 0);
@@ -387,25 +384,24 @@ child_setup (in, out, err, new_argv, set_pgrp, current_dir)
      If using vfork and C_ALLOCA it is safe because that changes
      the superior's static variables as if the superior had done alloca
      and will be cleaned up in the usual way.  */
-  {
-    register unsigned char *temp;
-    register int i;
 
-    i = XSTRING (current_dir)->size;
-    temp = (unsigned char *) alloca (i + 2);
-    bcopy (XSTRING (current_dir)->data, temp, i);
-    if (temp[i - 1] != '/') temp[i++] = '/';
-    temp[i] = 0;
-
-    /* We can't signal an Elisp error here; we're in a vfork.  Since
-       the callers check the current directory before forking, this
-       should only return an error if the directory's permissions
-       are changed between the check and this chdir, but we should
-       at least check.  */
-    if (chdir (temp) < 0)
-      exit (errno);
-  }
+  if (XTYPE (current_buffer->directory) == Lisp_String)
+    {
+      register unsigned char *temp;
+      register int i;
+
+      i = XSTRING (current_buffer->directory)->size;
+      temp = (unsigned char *) alloca (i + 2);
+      bcopy (XSTRING (current_buffer->directory)->data, temp, i);
+      if (temp[i - 1] != '/') temp[i++] = '/';
+      temp[i] = 0;
+      /* Switch to that directory, and report any error.  */
+      if (chdir (temp) < 0)
+        report_file_error ("In chdir",
+                           Fcons (current_buffer->directory, Qnil));
+    }
 
+#ifndef MAINTAIN_ENVIRONMENT
   /* Set `env' to a vector of the strings in Vprocess_environment.  */
   {
     register Lisp_Object tem;
@@ -422,7 +418,7 @@ child_setup (in, out, err, new_argv, set_pgrp, current_dir)
     /* new_length + 1 to include terminating 0 */
     env = new_env = (char **) alloca ((new_length + 1) * sizeof (char *));
 
-    /* Copy the Vprocess_alist strings into new_env.  */
+    /* Copy the env strings into new_env.  */
     for (tem = Vprocess_environment;
          (XTYPE (tem) == Lisp_Cons
           && XTYPE (XCONS (tem)->car) == Lisp_String);
@@ -430,6 +426,7 @@ child_setup (in, out, err, new_argv, set_pgrp, current_dir)
       *new_env++ = (char *) XSTRING (XCONS (tem)->car)->data;
     *new_env = 0;
   }
+#endif /* Not MAINTAIN_ENVIRONMENT */
 
   close (0);
   close (1);
@@ -442,11 +439,6 @@ child_setup (in, out, err, new_argv, set_pgrp, current_dir)
   close (out);
   close (err);
 
-#ifdef USG
-  setpgrp ();                   /* No arguments but equivalent in this case */
-#else
-  setpgrp (pid, pid);
-#endif /* USG */
   setpgrp_of_tty (pid);
 
 #ifdef vipc
@@ -464,111 +456,38 @@ child_setup (in, out, err, new_argv, set_pgrp, current_dir)
   _exit (1);
 }
 
-static int
-getenv_internal (var, varlen, value, valuelen)
-     char *var;
-     int varlen;
-     char **value;
-     int *valuelen;
-{
-  Lisp_Object scan;
-
-  for (scan = Vprocess_environment; CONSP (scan); scan = XCONS (scan)->cdr)
-    {
-      Lisp_Object entry = XCONS (scan)->car;
-      
-      if (XTYPE (entry) == Lisp_String
-          && XSTRING (entry)->size > varlen
-          && XSTRING (entry)->data[varlen] == '='
-          && ! bcmp (XSTRING (entry)->data, var, varlen))
-        {
-          *value    = (char *) XSTRING (entry)->data + (varlen + 1);
-          *valuelen = XSTRING (entry)->size - (varlen + 1);
-          return 1;
-        }
-    }
-
-  return 0;
-}
-
-DEFUN ("getenv", Fgetenv, Sgetenv, 1, 2, 0,
-  "Return the value of environment variable VAR, as a string.\n\
-VAR should be a string.  Value is nil if VAR is undefined in the environment.\n\
-This function consults the variable ``process-environment'' for its value.")
-  (var)
-     Lisp_Object var;
-{
-  char *value;
-  int valuelen;
-
-  CHECK_STRING (var, 0);
-  if (getenv_internal (XSTRING (var)->data, XSTRING (var)->size,
-                       &value, &valuelen))
-    return make_string (value, valuelen);
-  else
-    return Qnil;
-}
-
-/* A version of getenv that consults process_environment, easily
-   callable from C.  */
-char *
-egetenv (var)
-     char *var;
-{
-  char *value;
-  int valuelen;
-
-  if (getenv_internal (var, strlen (var), &value, &valuelen))
-    return value;
-  else
-    return 0;
-}
-
 #endif /* not VMS */
 
 init_callproc ()
 {
   register char * sh;
   register char **envp;
-  Lisp_Object tempdir;
+  Lisp_Object execdir;
 
-  {
-    char *data_dir = egetenv ("EMACSDATA");
-    
-    Vdata_directory =
-      Ffile_name_as_directory
-        (build_string (data_dir ? data_dir : PATH_DATA));
-  }
-
-  /* Check the EMACSPATH environment variable, defaulting to the
-     PATH_EXEC path from paths.h.  */
-  Vexec_path = decode_env_path ("EMACSPATH", PATH_EXEC);
+  /* Turn PATH_EXEC into a path.  `==' is just a string which we know
+     will not be the name of an environment variable.  */
+  Vexec_path = decode_env_path ("==", PATH_EXEC);
   Vexec_directory = Ffile_name_as_directory (Fcar (Vexec_path));
   Vexec_path = nconc2 (decode_env_path ("PATH", ""), Vexec_path);
 
-  tempdir = Fdirectory_file_name (Vexec_directory);
-  if (access (XSTRING (tempdir)->data, 0) < 0)
+  execdir = Fdirectory_file_name (Vexec_directory);
+  if (access (XSTRING (execdir)->data, 0) < 0)
     {
-      printf ("Warning: arch-dependent data dir (%s) does not exist.\n",
+      printf ("Warning: executable/documentation dir (%s) does not exist.\n",
               XSTRING (Vexec_directory)->data);
       sleep (2);
     }
 
-  tempdir = Fdirectory_file_name (Vdata_directory);
-  if (access (XSTRING (tempdir)->data, 0) < 0)
-    {
-      printf ("Warning: arch-independent data dir (%s) does not exist.\n",
-              XSTRING (Vdata_directory)->data);
-      sleep (2);
-    }
-
 #ifdef VMS
   Vshell_file_name = build_string ("*dcl*");
 #else
-  sh = (char *) getenv ("SHELL");
+  sh = (char *) egetenv ("SHELL");
   Vshell_file_name = build_string (sh ? sh : "/bin/sh");
 #endif
 
+#ifndef MAINTAIN_ENVIRONMENT
+  /* The equivalent of this operation was done
+     in init_environ in environ.c if MAINTAIN_ENVIRONMENT */
   Vprocess_environment = Qnil;
 #ifndef CANNOT_DUMP
   if (initialized)
@@ -576,6 +495,7 @@ init_callproc ()
     for (envp = environ; *envp; envp++)
       Vprocess_environment = Fcons (build_string (*envp),
                                     Vprocess_environment);
+#endif /* MAINTAIN_ENVIRONMENT */
 }
 
 syms_of_callproc ()
@@ -589,22 +509,17 @@ Initialized from the SHELL environment variable.");
 Each element is a string (directory name) or nil (try default directory).");
 
   DEFVAR_LISP ("exec-directory", &Vexec_directory,
-    "Directory of architecture-dependent files that come with GNU Emacs,\n\
-especially executable programs intended for Emacs to invoke.");
-
-  DEFVAR_LISP ("data-directory", &Vdata_directory,
-    "Directory of architecture-independent files that come with GNU Emacs,\n\
-intended for Emacs to use.");
+    "Directory that holds programs that come with GNU Emacs,\n\
+intended for Emacs to invoke.");
 
+#ifndef MAINTAIN_ENVIRONMENT
   DEFVAR_LISP ("process-environment", &Vprocess_environment,
-    "List of environment variables for subprocesses to inherit.\n\
-Each element should be a string of the form ENVVARNAME=VALUE.\n\
-The environment which Emacs inherits is placed in this variable\n\
-when Emacs starts.");
+    "List of strings to append to environment of subprocesses that are started.\n\
+Each string should have the format ENVVARNAME=VALUE.");
+#endif
 
 #ifndef VMS
   defsubr (&Scall_process);
 #endif
-  defsubr (&Sgetenv);
   defsubr (&Scall_process_region);
 }