emacs.c

/* Fully extensible Emacs, running on Unix, intended for GNU.

Copyright (C) 1985-1987, 1993-1995, 1997-1999, 2001-2013 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 3 of the License, or
(at your option) any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */


#include <config.h>
#include <errno.h>
#include <stdio.h>

#include <sys/types.h>
#include <sys/file.h>
#include <unistd.h>

#include <close-stream.h>

#include "lisp.h"

#ifdef WINDOWSNT
#include <fcntl.h>
#include <sys/socket.h>
#include "w32.h"
#include "w32heap.h"
#endif

#if defined WINDOWSNT || defined HAVE_NTGUI
#include "w32select.h"
#include "w32font.h"
#include "w32common.h"
#endif

#if defined CYGWIN
#include "cygw32.h"
#endif

#ifdef HAVE_WINDOW_SYSTEM
#include TERM_HEADER
#endif /* HAVE_WINDOW_SYSTEM */

#ifdef NS_IMPL_GNUSTEP
/* At least under Debian, GSConfig is in a subdirectory.  --Stef  */
#include <GNUstepBase/GSConfig.h>
#endif

#include "commands.h"
#include "intervals.h"
#include "character.h"
#include "buffer.h"
#include "window.h"

#include "systty.h"
#include "atimer.h"
#include "blockinput.h"
#include "syssignal.h"
#include "process.h"
#include "frame.h"
#include "termhooks.h"
#include "keyboard.h"
#include "keymap.h"

#ifdef HAVE_GNUTLS
#include "gnutls.h"
#endif

#if (defined PROFILING \
     && (defined __FreeBSD__ || defined GNU_LINUX || defined __MINGW32__))
# include <sys/gmon.h>
extern void moncontrol (int mode);
#endif

#ifdef HAVE_SETLOCALE
#include <locale.h>
#endif

#ifdef HAVE_SETRLIMIT
#include <sys/time.h>
#include <sys/resource.h>
#endif

#ifdef HAVE_PERSONALITY_LINUX32
#include <sys/personality.h>
#endif

static const char emacs_version[] = VERSION;
static const char emacs_copyright[] = COPYRIGHT;

/* Empty lisp strings.  To avoid having to build any others.  */
Lisp_Object empty_unibyte_string, empty_multibyte_string;

#ifdef WINDOWSNT
/* Cache for externally loaded libraries.  */
Lisp_Object Vlibrary_cache;
#endif

/* Set after Emacs has started up the first time.
   Prevents reinitialization of the Lisp world and keymaps
   on subsequent starts.  */
bool initialized;

#ifdef DARWIN_OS
extern void unexec_init_emacs_zone (void);
#endif

#ifdef DOUG_LEA_MALLOC
/* Preserves a pointer to the memory allocated that copies that
   static data inside glibc's malloc.  */
static void *malloc_state_ptr;
/* From glibc, a routine that returns a copy of the malloc internal state.  */
extern void *malloc_get_state (void);
/* From glibc, a routine that overwrites the malloc internal state.  */
extern int malloc_set_state (void*);
/* True if the MALLOC_CHECK_ environment variable was set while
   dumping.  Used to work around a bug in glibc's malloc.  */
static bool malloc_using_checking;
#elif defined HAVE_PTHREAD && !defined SYSTEM_MALLOC
extern void malloc_enable_thread (void);
#endif

Lisp_Object Qfile_name_handler_alist;

Lisp_Object Qrisky_local_variable;

Lisp_Object Qkill_emacs;
static Lisp_Object Qkill_emacs_hook;

/* If true, Emacs should not attempt to use a window-specific code,
   but instead should use the virtual terminal under which it was started.  */
bool inhibit_window_system;

/* If true, a filter or a sentinel is running.  Tested to save the match
   data on the first attempt to change it inside asynchronous code.  */
bool running_asynch_code;

#if defined (HAVE_X_WINDOWS) || defined (HAVE_NS)
/* If true, -d was specified, meaning we're using some window system.  */
bool display_arg;
#endif

/* An address near the bottom of the stack.
   Tells GC how to save a copy of the stack.  */
char *stack_bottom;

#if defined (DOUG_LEA_MALLOC) || defined (GNU_LINUX)
/* The address where the heap starts (from the first sbrk (0) call).  */
static void *my_heap_start;
#endif

#ifdef GNU_LINUX
/* The gap between BSS end and heap start as far as we can tell.  */
static uprintmax_t heap_bss_diff;
#endif

/* To run as a daemon under Cocoa or Windows, we must do a fork+exec,
   not a simple fork.

   On Cocoa, CoreFoundation lib fails in forked process:
   http://developer.apple.com/ReleaseNotes/
   CoreFoundation/CoreFoundation.html)

   On Windows, a Cygwin fork child cannot access the USER subsystem.

   We mark being in the exec'd process by a daemon name argument of
   form "--daemon=\nFD0,FD1\nNAME" where FD are the pipe file descriptors,
   NAME is the original daemon name, if any. */
#if defined NS_IMPL_COCOA || (defined HAVE_NTGUI && defined CYGWIN)
# define DAEMON_MUST_EXEC
#endif

/* True means running Emacs without interactive terminal.  */
bool noninteractive;

/* True means remove site-lisp directories from load-path.  */
bool no_site_lisp;

/* Name for the server started by the daemon.*/
static char *daemon_name;

/* Pipe used to send exit notification to the daemon parent at
   startup.  */
int daemon_pipe[2];

/* Save argv and argc.  */
char **initial_argv;
int initial_argc;

static void sort_args (int argc, char **argv);
static void syms_of_emacs (void);

/* C89 needs each string be at most 509 characters, so the usage
   strings below are split to not overflow this limit.  */
static char const *const usage_message[] =
  { "\
\n\
Run Emacs, the extensible, customizable, self-documenting real-time\n\
display editor.  The recommended way to start Emacs for normal editing\n\
is with no options at all.\n\
\n\
Run M-x info RET m emacs RET m emacs invocation RET inside Emacs to\n\
read the main documentation for these command-line arguments.\n\
\n\
Initialization options:\n\
\n\
",
    "\
--batch                     do not do interactive display; implies -q\n\
--chdir DIR                 change to directory DIR\n\
--daemon                    start a server in the background\n\
--debug-init                enable Emacs Lisp debugger for init file\n\
--display, -d DISPLAY       use X server DISPLAY\n\
",
    "\
--no-desktop                do not load a saved desktop\n\
--no-init-file, -q          load neither ~/.emacs nor default.el\n\
--no-shared-memory, -nl     do not use shared memory\n\
--no-site-file              do not load site-start.el\n\
--no-site-lisp, -nsl        do not add site-lisp directories to load-path\n\
--no-splash                 do not display a splash screen on startup\n\
--no-window-system, -nw     do not communicate with X, ignoring $DISPLAY\n\
",
    "\
--quick, -Q                 equivalent to:\n\
                              -q --no-site-file --no-site-lisp --no-splash\n\
--script FILE               run FILE as an Emacs Lisp script\n\
--terminal, -t DEVICE       use DEVICE for terminal I/O\n\
--user, -u USER             load ~USER/.emacs instead of your own\n\
\n\
",
    "\
Action options:\n\
\n\
FILE                    visit FILE using find-file\n\
+LINE                   go to line LINE in next FILE\n\
+LINE:COLUMN            go to line LINE, column COLUMN, in next FILE\n\
--directory, -L DIR     add DIR to variable load-path\n\
--eval EXPR             evaluate Emacs Lisp expression EXPR\n\
--execute EXPR          evaluate Emacs Lisp expression EXPR\n\
",
    "\
--file FILE             visit FILE using find-file\n\
--find-file FILE        visit FILE using find-file\n\
--funcall, -f FUNC      call Emacs Lisp function FUNC with no arguments\n\
--insert FILE           insert contents of FILE into current buffer\n\
--kill                  exit without asking for confirmation\n\
--load, -l FILE         load Emacs Lisp FILE using the load function\n\
--visit FILE            visit FILE using find-file\n\
\n\
",
    "\
Display options:\n\
\n\
--background-color, -bg COLOR   window background color\n\
--basic-display, -D             disable many display features;\n\
                                  used for debugging Emacs\n\
--border-color, -bd COLOR       main border color\n\
--border-width, -bw WIDTH       width of main border\n\
",
    "\
--color, --color=MODE           override color mode for character terminals;\n\
                                  MODE defaults to `auto', and\n\
                                  can also be `never', `always',\n\
                                  or a mode name like `ansi8'\n\
--cursor-color, -cr COLOR       color of the Emacs cursor indicating point\n\
--font, -fn FONT                default font; must be fixed-width\n\
--foreground-color, -fg COLOR   window foreground color\n\
",
    "\
--fullheight, -fh               make the first frame high as the screen\n\
--fullscreen, -fs               make the first frame fullscreen\n\
--fullwidth, -fw                make the first frame wide as the screen\n\
--maximized, -mm                make the first frame maximized\n\
--geometry, -g GEOMETRY         window geometry\n\
",
    "\
--no-bitmap-icon, -nbi          do not use picture of gnu for Emacs icon\n\
--iconic                        start Emacs in iconified state\n\
--internal-border, -ib WIDTH    width between text and main border\n\
--line-spacing, -lsp PIXELS     additional space to put between lines\n\
--mouse-color, -ms COLOR        mouse cursor color in Emacs window\n\
--name NAME                     title for initial Emacs frame\n\
",
    "\
--no-blinking-cursor, -nbc      disable blinking cursor\n\
--reverse-video, -r, -rv        switch foreground and background\n\
--title, -T TITLE               title for initial Emacs frame\n\
--vertical-scroll-bars, -vb     enable vertical scroll bars\n\
--xrm XRESOURCES                set additional X resources\n\
--parent-id XID                 set parent window\n\
--help                          display this help and exit\n\
--version                       output version information and exit\n\
\n\
",
    "\
You can generally also specify long option names with a single -; for\n\
example, -batch as well as --batch.  You can use any unambiguous\n\
abbreviation for a --option.\n\
\n\
Various environment variables and window system resources also affect\n\
Emacs' operation.  See the main documentation.\n\
\n\
Report bugs to bug-gnu-emacs@gnu.org.  First, please see the Bugs\n\
section of the Emacs manual or the file BUGS.\n"
  };


/* True if handling a fatal error already.  */
bool fatal_error_in_progress;

#ifdef HAVE_NS
/* NS autrelease pool, for memory management.  */
static void *ns_pool;
#endif

#if !HAVE_SETLOCALE
static char *
setlocale (int cat, char const *locale)
{
  return 0;
}
#endif


/* Report a fatal error due to signal SIG, output a backtrace of at
   most BACKTRACE_LIMIT lines, and exit.  */
_Noreturn void
terminate_due_to_signal (int sig, int backtrace_limit)
{
  signal (sig, SIG_DFL);
  totally_unblock_input ();

  /* If fatal error occurs in code below, avoid infinite recursion.  */
  if (! fatal_error_in_progress)
    {
      fatal_error_in_progress = 1;

      if (sig == SIGTERM || sig == SIGHUP || sig == SIGINT)
        Fkill_emacs (make_number (sig));

      shut_down_emacs (sig, Qnil);
      emacs_backtrace (backtrace_limit);
    }

  /* Signal the same code; this time it will really be fatal.
     Since we're in a signal handler, the signal is blocked, so we
     have to unblock it if we want to really receive it.  */
#ifndef MSDOS
  {
    sigset_t unblocked;
    sigemptyset (&unblocked);
    sigaddset (&unblocked, sig);
    pthread_sigmask (SIG_UNBLOCK, &unblocked, 0);
  }
#endif

  emacs_raise (sig);

  /* This shouldn't be executed, but it prevents a warning.  */
  exit (1);
}

/* Code for dealing with Lisp access to the Unix command line.  */

static void
init_cmdargs (int argc, char **argv, int skip_args)
{
  register int i;
  Lisp_Object name, dir, handler;
  ptrdiff_t count = SPECPDL_INDEX ();
  Lisp_Object raw_name;

  initial_argv = argv;
  initial_argc = argc;

  raw_name = build_string (argv[0]);

  /* Add /: to the front of the name
     if it would otherwise be treated as magic.  */
  handler = Ffind_file_name_handler (raw_name, Qt);
  if (! NILP (handler))
    raw_name = concat2 (build_string ("/:"), raw_name);

  Vinvocation_name = Ffile_name_nondirectory (raw_name);
  Vinvocation_directory = Ffile_name_directory (raw_name);

  /* If we got no directory in argv[0], search PATH to find where
     Emacs actually came from.  */
  if (NILP (Vinvocation_directory))
    {
      Lisp_Object found;
      int yes = openp (Vexec_path, Vinvocation_name,
		       Vexec_suffixes, &found, make_number (X_OK));
      if (yes == 1)
	{
	  /* Add /: to the front of the name
	     if it would otherwise be treated as magic.  */
	  handler = Ffind_file_name_handler (found, Qt);
	  if (! NILP (handler))
	    found = concat2 (build_string ("/:"), found);
	  Vinvocation_directory = Ffile_name_directory (found);
	}
    }

  if (!NILP (Vinvocation_directory)
      && NILP (Ffile_name_absolute_p (Vinvocation_directory)))
    /* Emacs was started with relative path, like ./emacs.
       Make it absolute.  */
    Vinvocation_directory = Fexpand_file_name (Vinvocation_directory, Qnil);

  Vinstallation_directory = Qnil;

  if (!NILP (Vinvocation_directory))
    {
      dir = Vinvocation_directory;
#ifdef WINDOWSNT
      /* If we are running from the build directory, set DIR to the
	 src subdirectory of the Emacs tree, like on Posix
	 platforms.  */
      if (SBYTES (dir) > sizeof ("/i386/") - 1
	  && 0 == strcmp (SSDATA (dir) + SBYTES (dir) - sizeof ("/i386/") + 1,
			  "/i386/"))
	dir = Fexpand_file_name (build_string ("../.."), dir);
#else  /* !WINDOWSNT */
#endif
      name = Fexpand_file_name (Vinvocation_name, dir);
      while (1)
	{
	  Lisp_Object tem, lib_src_exists;
	  Lisp_Object etc_exists, info_exists;

	  /* See if dir contains subdirs for use by Emacs.
	     Check for the ones that would exist in a build directory,
	     not including lisp and info.  */
	  tem = Fexpand_file_name (build_string ("lib-src"), dir);
	  lib_src_exists = Ffile_exists_p (tem);

#ifdef MSDOS
	  /* MSDOS installations frequently remove lib-src, but we still
	     must set installation-directory, or else info won't find
	     its files (it uses the value of installation-directory).  */
	  tem = Fexpand_file_name (build_string ("info"), dir);
	  info_exists = Ffile_exists_p (tem);
#else
	  info_exists = Qnil;
#endif

	  if (!NILP (lib_src_exists) || !NILP (info_exists))
	    {
	      tem = Fexpand_file_name (build_string ("etc"), dir);
	      etc_exists = Ffile_exists_p (tem);
	      if (!NILP (etc_exists))
		{
		  Vinstallation_directory
		    = Ffile_name_as_directory (dir);
		  break;
		}
	    }

	  /* See if dir's parent contains those subdirs.  */
	  tem = Fexpand_file_name (build_string ("../lib-src"), dir);
	  lib_src_exists = Ffile_exists_p (tem);


#ifdef MSDOS
	  /* See the MSDOS commentary above.  */
	  tem = Fexpand_file_name (build_string ("../info"), dir);
	  info_exists = Ffile_exists_p (tem);
#else
	  info_exists = Qnil;
#endif

	  if (!NILP (lib_src_exists) || !NILP (info_exists))
	    {
	      tem = Fexpand_file_name (build_string ("../etc"), dir);
	      etc_exists = Ffile_exists_p (tem);
	      if (!NILP (etc_exists))
		{
		  tem = Fexpand_file_name (build_string (".."), dir);
		  Vinstallation_directory
		    = Ffile_name_as_directory (tem);
		  break;
		}
	    }

	  /* If the Emacs executable is actually a link,
	     next try the dir that the link points into.  */
	  tem = Ffile_symlink_p (name);
	  if (!NILP (tem))
	    {
	      name = Fexpand_file_name (tem, dir);
	      dir = Ffile_name_directory (name);
	    }
	  else
	    break;
	}
    }

  Vcommand_line_args = Qnil;

  for (i = argc - 1; i >= 0; i--)
    {
      if (i == 0 || i > skip_args)
	/* For the moment, we keep arguments as is in unibyte strings.
	   They are decoded in the function command-line after we know
	   locale-coding-system.  */
	Vcommand_line_args
	  = Fcons (build_unibyte_string (argv[i]), Vcommand_line_args);
    }

  unbind_to (count, Qnil);
}

DEFUN ("invocation-name", Finvocation_name, Sinvocation_name, 0, 0, 0,
       doc: /* Return the program name that was used to run Emacs.
Any directory names are omitted.  */)
  (void)
{
  return Fcopy_sequence (Vinvocation_name);
}

DEFUN ("invocation-directory", Finvocation_directory, Sinvocation_directory,
       0, 0, 0,
       doc: /* Return the directory name in which the Emacs executable was located.  */)
  (void)
{
  return Fcopy_sequence (Vinvocation_directory);
}


#ifdef HAVE_TZSET
/* A valid but unlikely value for the TZ environment value.
   It is OK (though a bit slower) if the user actually chooses this value.  */
static char const dump_tz[] = "UtC0";
#endif

/* Test whether the next argument in ARGV matches SSTR or a prefix of
   LSTR (at least MINLEN characters).  If so, then if VALPTR is non-null
   (the argument is supposed to have a value) store in *VALPTR either
   the next argument or the portion of this one after the equal sign.
   ARGV is read starting at position *SKIPPTR; this index is advanced
   by the number of arguments used.

   Too bad we can't just use getopt for all of this, but we don't have
   enough information to do it right.  */

static bool
argmatch (char **argv, int argc, const char *sstr, const char *lstr,
          int minlen, char **valptr, int *skipptr)
{
  char *p = NULL;
  ptrdiff_t arglen;
  char *arg;

  /* Don't access argv[argc]; give up in advance.  */
  if (argc <= *skipptr + 1)
    return 0;

  arg = argv[*skipptr+1];
  if (arg == NULL)
    return 0;
  if (strcmp (arg, sstr) == 0)
    {
      if (valptr != NULL)
	{
	  *valptr = argv[*skipptr+2];
	  *skipptr += 2;
	}
      else
	*skipptr += 1;
      return 1;
    }
  arglen = (valptr != NULL && (p = strchr (arg, '=')) != NULL
	    ? p - arg : strlen (arg));
  if (lstr == 0 || arglen < minlen || strncmp (arg, lstr, arglen) != 0)
    return 0;
  else if (valptr == NULL)
    {
      *skipptr += 1;
      return 1;
    }
  else if (p != NULL)
    {
      *valptr = p+1;
      *skipptr += 1;
      return 1;
    }
  else if (argv[*skipptr+2] != NULL)
    {
      *valptr = argv[*skipptr+2];
      *skipptr += 2;
      return 1;
    }
  else
    {
      return 0;
    }
}

#ifdef DOUG_LEA_MALLOC

/* malloc can be invoked even before main (e.g. by the dynamic
   linker), so the dumped malloc state must be restored as early as
   possible using this special hook.  */

static void
malloc_initialize_hook (void)
{
  if (initialized)
    {
      if (!malloc_using_checking)
	/* Work around a bug in glibc's malloc.  MALLOC_CHECK_ must be
	   ignored if the heap to be restored was constructed without
	   malloc checking.  Can't use unsetenv, since that calls malloc.  */
	{
	  char **p;

	  for (p = environ; p && *p; p++)
	    if (strncmp (*p, "MALLOC_CHECK_=", 14) == 0)
	      {
		do
		  *p = p[1];
		while (*++p);
		break;
	      }
	}

      malloc_set_state (malloc_state_ptr);
#ifndef XMALLOC_OVERRUN_CHECK
      free (malloc_state_ptr);
#endif
    }
  else
    {
      if (my_heap_start == 0)
        my_heap_start = sbrk (0);
      malloc_using_checking = getenv ("MALLOC_CHECK_") != NULL;
    }
}

void (*__malloc_initialize_hook) (void) EXTERNALLY_VISIBLE = malloc_initialize_hook;

#endif /* DOUG_LEA_MALLOC */

/* Close standard output and standard error, reporting any write
   errors as best we can.  This is intended for use with atexit.  */
static void
close_output_streams (void)
{
  if (close_stream (stdout) != 0)
    {
      emacs_perror ("Write error to standard output");
      _exit (EXIT_FAILURE);
    }

   if (close_stream (stderr) != 0)
     _exit (EXIT_FAILURE);
}

/* ARGSUSED */
int
main (int argc, char **argv)
{
#if GC_MARK_STACK
  Lisp_Object dummy;
#endif
  char stack_bottom_variable;
  bool do_initial_setlocale;
  bool dumping;
  int skip_args = 0;
#ifdef HAVE_SETRLIMIT
  struct rlimit rlim;
#endif
  bool no_loadup = 0;
  char *junk = 0;
  char *dname_arg = 0;
#ifdef DAEMON_MUST_EXEC
  char dname_arg2[80];
#endif
  char *ch_to_dir;

#if GC_MARK_STACK
  stack_base = &dummy;
#endif

#ifdef G_SLICE_ALWAYS_MALLOC
  /* This is used by the Cygwin build.  */
  xputenv ("G_SLICE=always-malloc");
#endif

#ifdef GNU_LINUX
  if (!initialized)
    {
      extern char my_endbss[];
      extern char *my_endbss_static;

      if (my_heap_start == 0)
        my_heap_start = sbrk (0);

      heap_bss_diff = (char *)my_heap_start - max (my_endbss, my_endbss_static);
    }
#endif

#if defined WINDOWSNT || defined HAVE_NTGUI
  /* Set global variables used to detect Windows version.  Do this as
     early as possible.  (unexw32.c calls this function as well, but
     the additional call here is harmless.) */
  cache_system_info ();
#endif

#ifdef RUN_TIME_REMAP
  if (initialized)
    run_time_remap (argv[0]);
#endif

/* If using unexmacosx.c (set by s/darwin.h), we must do this. */
#ifdef DARWIN_OS
  if (!initialized)
    unexec_init_emacs_zone ();
#endif

  atexit (close_output_streams);

  sort_args (argc, argv);
  argc = 0;
  while (argv[argc]) argc++;

  if (argmatch (argv, argc, "-version", "--version", 3, NULL, &skip_args))
    {
      const char *version, *copyright;
      if (initialized)
	{
	  Lisp_Object tem, tem2;
	  tem = Fsymbol_value (intern_c_string ("emacs-version"));
	  tem2 = Fsymbol_value (intern_c_string ("emacs-copyright"));
	  if (!STRINGP (tem))
	    {
	      fprintf (stderr, "Invalid value of `emacs-version'\n");
	      exit (1);
	    }
	  if (!STRINGP (tem2))
	    {
	      fprintf (stderr, "Invalid value of `emacs-copyright'\n");
	      exit (1);
	    }
	  else
	    {
	      version = SSDATA (tem);
	      copyright = SSDATA (tem2);
	    }
	}
      else
	{
	  version = emacs_version;
	  copyright = emacs_copyright;
	}
      printf ("GNU Emacs %s\n", version);
      printf ("%s\n", copyright);
      printf ("GNU Emacs comes with ABSOLUTELY NO WARRANTY.\n");
      printf ("You may redistribute copies of Emacs\n");
      printf ("under the terms of the GNU General Public License.\n");
      printf ("For more information about these matters, ");
      printf ("see the file named COPYING.\n");
      exit (0);
    }

  if (argmatch (argv, argc, "-chdir", "--chdir", 4, &ch_to_dir, &skip_args))
    if (chdir (ch_to_dir) == -1)
      {
	fprintf (stderr, "%s: Can't chdir to %s: %s\n",
		 argv[0], ch_to_dir, strerror (errno));
	exit (1);
      }

  dumping = !initialized && (strcmp (argv[argc - 1], "dump") == 0
			     || strcmp (argv[argc - 1], "bootstrap") == 0);

#ifdef HAVE_PERSONALITY_LINUX32
  if (dumping && ! getenv ("EMACS_HEAP_EXEC"))
    {
      /* Set this so we only do this once.  */
      xputenv ("EMACS_HEAP_EXEC=true");

      /* A flag to turn off address randomization which is introduced
         in linux kernel shipped with fedora core 4 */
#define ADD_NO_RANDOMIZE 0x0040000
      personality (PER_LINUX32 | ADD_NO_RANDOMIZE);
#undef  ADD_NO_RANDOMIZE

      execvp (argv[0], argv);

      /* If the exec fails, try to dump anyway.  */
      emacs_perror (argv[0]);
    }
#endif /* HAVE_PERSONALITY_LINUX32 */

#if defined (HAVE_SETRLIMIT) && defined (RLIMIT_STACK)
  /* Extend the stack space available.
     Don't do that if dumping, since some systems (e.g. DJGPP)
     might define a smaller stack limit at that time.  */
  if (1
#ifndef CANNOT_DUMP
      && (!noninteractive || initialized)
#endif
      && !getrlimit (RLIMIT_STACK, &rlim))
    {
      long newlim;
      extern size_t re_max_failures;
      /* Approximate the amount regex.c needs per unit of re_max_failures.  */
      int ratio = 20 * sizeof (char *);
      /* Then add 33% to cover the size of the smaller stacks that regex.c
	 successively allocates and discards, on its way to the maximum.  */
      ratio += ratio / 3;
      /* Add in some extra to cover
	 what we're likely to use for other reasons.  */
      newlim = re_max_failures * ratio + 200000;
#ifdef __NetBSD__
      /* NetBSD (at least NetBSD 1.2G and former) has a bug in its
       stack allocation routine for new process that the allocation
       fails if stack limit is not on page boundary.  So, round up the
       new limit to page boundary.  */
      newlim = (newlim + getpagesize () - 1) / getpagesize () * getpagesize ();
#endif
      if (newlim > rlim.rlim_max)
	{
	  newlim = rlim.rlim_max;
	  /* Don't let regex.c overflow the stack we have.  */
	  re_max_failures = (newlim - 200000) / ratio;
	}
      if (rlim.rlim_cur < newlim)
	rlim.rlim_cur = newlim;

      setrlimit (RLIMIT_STACK, &rlim);
    }
#endif /* HAVE_SETRLIMIT and RLIMIT_STACK */

  /* Record (approximately) where the stack begins.  */
  stack_bottom = &stack_bottom_variable;

  clearerr (stdin);

#ifndef SYSTEM_MALLOC
  /* Arrange to get warning messages as memory fills up.  */
  memory_warnings (0, malloc_warning);

  /* Call malloc at least once, to run malloc_initialize_hook.
     Also call realloc and free for consistency.  */
  free (realloc (malloc (4), 4));

#endif	/* not SYSTEM_MALLOC */

#if defined (MSDOS) || defined (WINDOWSNT)
  /* We do all file input/output as binary files.  When we need to translate
     newlines, we do that manually.  */
  _fmode = O_BINARY;
#endif /* MSDOS || WINDOWSNT */

#ifdef MSDOS
  if (!isatty (fileno (stdin)))
    setmode (fileno (stdin), O_BINARY);
  if (!isatty (fileno (stdout)))
    {
      fflush (stdout);
      setmode (fileno (stdout), O_BINARY);
    }
#endif /* MSDOS */

  /* Skip initial setlocale if LC_ALL is "C", as it's not needed in that case.
     The build procedure uses this while dumping, to ensure that the
     dumped Emacs does not have its system locale tables initialized,
     as that might cause screwups when the dumped Emacs starts up.  */
  {
    char *lc_all = getenv ("LC_ALL");
    do_initial_setlocale = ! lc_all || strcmp (lc_all, "C");
  }

  /* Set locale now, so that initial error messages are localized properly.
     fixup_locale must wait until later, since it builds strings.  */
  if (do_initial_setlocale)
    setlocale (LC_ALL, "");

  inhibit_window_system = 0;

  /* Handle the -t switch, which specifies filename to use as terminal.  */
  while (1)
    {
      char *term;
      if (argmatch (argv, argc, "-t", "--terminal", 4, &term, &skip_args))
	{
	  int result;
	  emacs_close (0);
	  emacs_close (1);
	  result = emacs_open (term, O_RDWR, 0);
	  if (result < 0 || fcntl (0, F_DUPFD_CLOEXEC, 1) < 0)
	    {
	      char *errstring = strerror (errno);
	      fprintf (stderr, "%s: %s: %s\n", argv[0], term, errstring);
	      exit (1);
	    }
	  if (! isatty (0))
	    {
	      fprintf (stderr, "%s: %s: not a tty\n", argv[0], term);
	      exit (1);
	    }
	  fprintf (stderr, "Using %s\n", term);
#ifdef HAVE_WINDOW_SYSTEM
	  inhibit_window_system = 1; /* -t => -nw */
#endif
	}
      else
	break;
    }

  /* Comman