emacs.c

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

Copyright (C) 1985-1987, 1993-1995, 1997-1999, 2001-2011
  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 <signal.h>
#include <errno.h>
#include <stdio.h>

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

#ifdef WINDOWSNT
#include <fcntl.h>
#include <windows.h> /* just for w32.h */
#include "w32.h"
#include "w32heap.h" /* for prototype of sbrk */
#endif

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

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

#include "systty.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

#ifdef HAVE_NS
#include "nsterm.h"
#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

#ifndef O_RDWR
#define O_RDWR 2
#endif

#ifdef HAVE_SETPGID
#if !defined (USG)
#undef setpgrp
#define setpgrp setpgid
#endif
#endif

static const char emacs_version[] = VERSION;
static const char emacs_copyright[] = "Copyright (C) 2011 Free Software Foundation, Inc.";

/* Make these values available in GDB, which doesn't see macros.  */

#ifdef USE_LSB_TAG
int gdb_use_lsb EXTERNALLY_VISIBLE = 1;
#else
int gdb_use_lsb EXTERNALLY_VISIBLE = 0;
#endif
#ifndef USE_LISP_UNION_TYPE
int gdb_use_union EXTERNALLY_VISIBLE  = 0;
#else
int gdb_use_union EXTERNALLY_VISIBLE = 1;
#endif
EMACS_INT gdb_valbits EXTERNALLY_VISIBLE = VALBITS;
EMACS_INT gdb_gctypebits EXTERNALLY_VISIBLE = GCTYPEBITS;
#if defined (DATA_SEG_BITS) && ! defined (USE_LSB_TAG)
EMACS_INT gdb_data_seg_bits EXTERNALLY_VISIBLE = DATA_SEG_BITS;
#else
EMACS_INT gdb_data_seg_bits EXTERNALLY_VISIBLE = 0;
#endif
EMACS_INT PVEC_FLAG EXTERNALLY_VISIBLE = PSEUDOVECTOR_FLAG;
EMACS_INT gdb_array_mark_flag EXTERNALLY_VISIBLE = ARRAY_MARK_FLAG;
/* GDB might say "No enum type named pvec_type" if we don't have at
   least one symbol with that type, and then xbacktrace could fail.  */
enum pvec_type gdb_pvec_type EXTERNALLY_VISIBLE = PVEC_TYPE_MASK;

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

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

#ifdef DOUG_LEA_MALLOC
/* Preserves a pointer to the memory allocated that copies that
   static data inside glibc's malloc.  */
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*);
/* Non-zero if the MALLOC_CHECK_ environment variable was set while
   dumping.  Used to work around a bug in glibc's malloc.  */
int malloc_using_checking;
#endif

Lisp_Object Qfile_name_handler_alist;

Lisp_Object Qrisky_local_variable;

/* If non-zero, emacs should not attempt to use a window-specific code,
   but instead should use the virtual terminal under which it was started.  */
int inhibit_window_system;

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

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

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

/* The address where the heap starts (from the first sbrk (0) call).  */
static void *my_heap_start;

/* The gap between BSS end and heap start as far as we can tell.  */
static unsigned long heap_bss_diff;

/* If the gap between BSS end and heap start is larger than this
   output a warning in dump-emacs.  */
#define MAX_HEAP_BSS_DIFF (1024*1024)

/* Nonzero means running Emacs without interactive terminal.  */

int noninteractive;

/* Nonzero means remove site-lisp directories from load-path.  */
int 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);
void syms_of_emacs (void);

/* MSVC needs each string be shorter than 2048 bytes, so the usage
   strings below are split to not overflow this limit.  */
#define USAGE1 "\
Usage: %s [OPTION-OR-FILENAME]...\n\
\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%s"

#define USAGE2 "\
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"

#define USAGE3 "\
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 can also\n\
                                  be `never', `auto', `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 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"

#define USAGE4 "\
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"


/* Signal code for the fatal signal that was received.  */
int fatal_error_code;

/* Nonzero if handling a fatal error already.  */
int fatal_error_in_progress;

/* If non-null, call this function from fatal_error_signal before
   committing suicide.  */

void (*fatal_error_signal_hook) (void);

#ifdef FORWARD_SIGNAL_TO_MAIN_THREAD
/* When compiled with GTK and running under Gnome,
   multiple threads may be created.  Keep track of our main
   thread to make sure signals are delivered to it (see syssignal.h).  */

pthread_t main_thread;
#endif


/* Handle bus errors, invalid instruction, etc.  */
SIGTYPE
fatal_error_signal (int sig)
{
  SIGNAL_THREAD_CHECK (sig);
  fatal_error_code = sig;
  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, 0, Qnil);
    }

  /* Signal the same code; this time it will really be fatal.
     Remember that since we're in a signal handler, the signal we're
     going to send is probably blocked, so we have to unblock it if we
     want to really receive it.  */
#ifndef MSDOS
  sigunblock (sigmask (fatal_error_code));
#endif

  if (fatal_error_signal_hook)
    fatal_error_signal_hook ();

  kill (getpid (), fatal_error_code);
}

#ifdef SIGDANGER

/* Handler for SIGDANGER.  */
SIGTYPE
memory_warning_signal (sig)
     int sig;
{
  signal (sig, memory_warning_signal);
  SIGNAL_THREAD_CHECK (sig);

  malloc_warning ("Operating system warns that virtual memory is running low.\n");

  /* It might be unsafe to call do_auto_save now.  */
  force_auto_save_soon ();
}
#endif

/* We define abort, rather than using it from the library,
   so that GDB can return from a breakpoint here.
   MSDOS has its own definition in msdos.c.  */

#if ! defined (DOS_NT) && ! defined (NO_ABORT)

void
abort (void)
{
  kill (getpid (), SIGABRT);
  /* This shouldn't be executed, but it prevents a warning.  */
  exit (1);
}
#endif


/* 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, tem;
  int 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.  */
  tem = Ffind_file_name_handler (raw_name, Qt);
  if (! NILP (tem))
    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.  */
	  tem = Ffind_file_name_handler (found, Qt);
	  if (! NILP (tem))
	    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;
      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 (make_unibyte_string (argv[i], strlen (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 dump_tz[] = "UtC0";
#endif

#ifndef ORDINARY_LINK
/* We don't include crtbegin.o and crtend.o in the link,
   so these functions and variables might be missed.
   Provide dummy definitions to avoid error.
   (We don't have any real constructors or destructors.)  */
#ifdef __GNUC__
#ifndef GCC_CTORS_IN_LIBC
void __do_global_ctors (void)
{}
void __do_global_ctors_aux (void)
{}
void __do_global_dtors (void)
{}
/* GNU/Linux has a bug in its library; avoid an error.  */
#ifndef GNU_LINUX
char * __CTOR_LIST__[2] = { (char *) (-1), 0 };
#endif
char * __DTOR_LIST__[2] = { (char *) (-1), 0 };
#endif /* GCC_CTORS_IN_LIBC */
void __main (void)
{}
#endif /* __GNUC__ */
#endif /* ORDINARY_LINK */

/* 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 int
argmatch (char **argv, int argc, const char *sstr, const char *lstr, int minlen, char **valptr, int *skipptr)
{
  char *p = NULL;
  int 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)
{
#ifndef USE_CRT_DLL
  extern char **environ;
#endif

  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) = malloc_initialize_hook;

#endif /* DOUG_LEA_MALLOC */


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

#if GC_MARK_STACK
  stack_base = &dummy;
#endif

#if defined (USE_GTK) && defined (G_SLICE_ALWAYS_MALLOC)
  /* This is used by the Cygwin build.  */
  setenv ("G_SLICE", "always-malloc", 1);
#endif

  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);
    }

#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

  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);
      }


#ifdef HAVE_PERSONALITY_LINUX32
  if (!initialized
      && (strcmp (argv[argc-1], "dump") == 0
          || strcmp (argv[argc-1], "bootstrap") == 0)
      && ! getenv ("EMACS_HEAP_EXEC"))
    {
      static char heapexec[] = "EMACS_HEAP_EXEC=true";
      /* Set this so we only do this once.  */
      putenv(heapexec);

      /* 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.  */
      perror ("execvp");
    }
#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 the initial __malloc_hook.
     Also call realloc and free for consistency.  */
  free (realloc (malloc (4), 4));

# ifndef SYNC_INPUT
  /* Arrange to disable interrupt input inside malloc etc.  */
  uninterrupt_malloc ();
# endif /* not SYNC_INPUT */
#endif	/* not SYSTEM_MALLOC */

#ifdef FORWARD_SIGNAL_TO_MAIN_THREAD
  main_thread = pthread_self ();
#endif /* FORWARD_SIGNAL_TO_MAIN_THREAD */

#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 || dup (0) < 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 */