emacs.c

/* Fully extensible Emacs, running on Unix, intended for GNU.
   Copyright (C) 1985, 86, 87, 93, 94, 95 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)
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; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */


#include <signal.h>
#include <errno.h>

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

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

#ifdef VMS
#include <ssdef.h>
#endif

#ifdef BSD_SYSTEM
#include <sys/ioctl.h>
#endif

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

#include "systty.h"
#include "blockinput.h"
#include "syssignal.h"
#include "process.h"

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

#ifndef O_RDWR
#define O_RDWR 2
#endif

extern void malloc_warning ();
extern void set_time_zone_rule ();
extern char *index ();
extern char *strerror ();

/* Command line args from shell, as list of strings */
Lisp_Object Vcommand_line_args;

/* The name under which Emacs was invoked, with any leading directory
   names discarded.  */
Lisp_Object Vinvocation_name;

/* The directory name from which Emacs was invoked.  */
Lisp_Object Vinvocation_directory;

/* The directory name in which to find subdirs such as lisp and etc.
   nil means get them only from PATH_LOADSEARCH.  */
Lisp_Object Vinstallation_directory;

/* Hook run by `kill-emacs' before it does really anything.  */
Lisp_Object Vkill_emacs_hook;

/* 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 ();
/* From glibc, a routine that overwrites the malloc internal state.  */
extern void malloc_set_state ();
#endif

/* Variable whose value is symbol giving operating system type.  */
Lisp_Object Vsystem_type;

/* Variable whose value is string giving configuration built for.  */
Lisp_Object Vsystem_configuration;

/* Variable whose value is string giving configuration options,
   for use when reporting bugs.  */
Lisp_Object Vsystem_configuration_options;

Lisp_Object Qfile_name_handler_alist;

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

/* If nonzero, set Emacs to run at this priority.  This is also used
   in child_setup and sys_suspend to make sure subshells run at normal
   priority; Those functions have their own extern declaration.  */
int emacs_priority;

/* 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;

#ifdef BSD_PGRPS
/* See sysdep.c.  */
extern int inherited_pgroup;
#endif

#ifdef HAVE_X_WINDOWS
/* 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;

#ifdef HAVE_WINDOW_SYSTEM
extern Lisp_Object Vwindow_system;
#endif /* HAVE_WINDOW_SYSTEM */

extern Lisp_Object Vauto_save_list_file_name;

#ifdef USG_SHARED_LIBRARIES
/* If nonzero, this is the place to put the end of the writable segment
   at startup.  */

unsigned int bss_end = 0;
#endif

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

int noninteractive;

/* Value of Lisp variable `noninteractive'.
   Normally same as C variable `noninteractive'
   but nothing terrible happens if user sets this one.  */

int noninteractive1;

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

static void sort_args ();

/* 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;

/* Handle bus errors, illegal instruction, etc. */
SIGTYPE
fatal_error_signal (sig)
     int 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;

      shut_down_emacs (sig, 0, Qnil);
    }

#ifdef VMS
  LIB$STOP (SS$_ABORT);
#else
  /* 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
  kill (getpid (), fatal_error_code);
#endif /* not VMS */
}

#ifdef SIGDANGER

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

  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

/* Code for dealing with Lisp access to the Unix command line */

static
init_cmdargs (argc, argv, skip_args)
     int argc;
     char **argv;
     int skip_args;
{
  register int i;
  Lisp_Object name, dir, tem;
  int count = specpdl_ptr - specpdl;
  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,
		       EXEC_SUFFIXES, &found, 1);
      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)
	Vcommand_line_args
	  = Fcons (build_string (argv[i]), Vcommand_line_args);
    }

  unbind_to (count, Qnil);
}

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

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


#ifdef VMS
#ifdef LINK_CRTL_SHARE
#ifdef SHARABLE_LIB_BUG
extern noshare char **environ;
#endif /* SHARABLE_LIB_BUG */
#endif /* LINK_CRTL_SHARE */
#endif /* VMS */

#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
__do_global_ctors ()
{}
__do_global_ctors_aux ()
{}
__do_global_dtors ()
{}
/* Linux has a bug in its library; avoid an error.  */
#ifndef LINUX
char * __CTOR_LIST__[2] = { (char *) (-1), 0 };
#endif
char * __DTOR_LIST__[2] = { (char *) (-1), 0 };
#endif /* GCC_CTORS_IN_LIBC */
__main ()
{}
#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 (argv, argc, sstr, lstr, minlen, valptr, skipptr)
     char **argv;
     int argc;
     char *sstr;
     char *lstr;
     int minlen;
     char **valptr;
     int *skipptr;
{
  char *p;
  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 = index (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;
    }
}

/* ARGSUSED */
main (argc, argv, envp)
     int argc;
     char **argv;
     char **envp;
{
  char stack_bottom_variable;
  int skip_args = 0;
  extern int errno;
  extern sys_nerr;
#ifdef HAVE_SETRLIMIT
  struct rlimit rlim;
#endif

#ifdef LINUX_SBRK_BUG
  __sbrk (1);
#endif

#ifdef DOUG_LEA_MALLOC
  if (initialized)
    {
      malloc_set_state (malloc_state_ptr);
      free (malloc_state_ptr);
    }
#endif

  sort_args (argc, argv);

  if (argmatch (argv, argc, "-version", "--version", 3, NULL, &skip_args))
    {
      Lisp_Object tem;
      tem = Fsymbol_value (intern ("emacs-version"));
      if (!STRINGP (tem))
	{
	  fprintf (stderr, "Invalid value of `emacs-version'\n");
	  exit (1);
	}
      else
	{
	  printf ("GNU Emacs %s\n", XSTRING (tem)->data);
	  printf ("Copyright (C) 1996 Free Software Foundation, Inc.\n");
	  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 files named COPYING.\n");
	  exit (0);
	}
    }

/* Map in shared memory, if we are using that.  */
#ifdef HAVE_SHM
  if (argmatch (argv, argc, "-nl", "--no-shared-memory", 6, NULL, &skip_args))
    {
      map_in_data (0);
      /* The shared memory was just restored, which clobbered this.  */
      skip_args = 1;
    }
  else
    {
      map_in_data (1);
      /* The shared memory was just restored, which clobbered this.  */
      skip_args = 0;
    }
#endif

#ifdef NeXT
  {
    extern int malloc_cookie;
    /* This helps out unexnext.c.  */
    if (initialized)
      if (malloc_jumpstart (malloc_cookie) != 0)
	printf ("malloc jumpstart failed!\n");
  }
#endif /* NeXT */

#ifdef VMS
  /* If -map specified, map the data file in */
  {
    char *file;
    if (argmatch (argv, argc, "-map", "--map-data", 3, &mapin_file, &skip_args))
      mapin_data (file);
  }

#ifdef LINK_CRTL_SHARE
#ifdef SHARABLE_LIB_BUG
  /* Bletcherous shared libraries! */
  if (!stdin)
    stdin = fdopen (0, "r");
  if (!stdout)
    stdout = fdopen (1, "w");
  if (!stderr)
    stderr = fdopen (2, "w");
  if (!environ)
    environ = envp;
#endif /* SHARABLE_LIB_BUG */
#endif /* LINK_CRTL_SHARE */
#endif /* VMS */

#ifdef HAVE_SETRLIMIT
  /* Extend the stack space available.  */
  if (!getrlimit (RLIMIT_STACK, &rlim))
    {
      long newlim;
      /* Approximate the amount regex.c needs, plus some more.  */
      newlim = 800000 * sizeof (char *);
      if (newlim > rlim.rlim_max)
	newlim = rlim.rlim_max;
      if (rlim.rlim_cur < newlim)
	rlim.rlim_cur = newlim;

      setrlimit (RLIMIT_STACK, &rlim);
    }
#endif

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

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

#ifdef USG_SHARED_LIBRARIES
  if (bss_end)
    brk ((void *)bss_end);
#endif

  clearerr (stdin);

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

      /* Arrange to disable interrupt input while malloc and friends are
	 running.  */
      uninterrupt_malloc ();
    }
#endif	/* not SYSTEM_MALLOC */

#ifdef MSDOS
  /* We do all file input/output as binary files.  When we need to translate
     newlines, we do that manually.  */
  _fmode = O_BINARY;

#if __DJGPP__ >= 2
  if (!isatty (fileno (stdin)))
    setmode (fileno (stdin), O_BINARY);
  if (!isatty (fileno (stdout)))
    {
      fflush (stdout);
      setmode (fileno (stdout), O_BINARY);
    }
#else  /* not __DJGPP__ >= 2 */
  (stdin)->_flag &= ~_IOTEXT;
  (stdout)->_flag &= ~_IOTEXT;
  (stderr)->_flag &= ~_IOTEXT;
#endif /* not __DJGPP__ >= 2 */
#endif /* MSDOS */

#ifdef SET_EMACS_PRIORITY
  if (emacs_priority)
    nice (emacs_priority);
  setuid (getuid ());
#endif /* SET_EMACS_PRIORITY */

#ifdef EXTRA_INITIALIZE
  EXTRA_INITIALIZE;
#endif

  inhibit_window_system = 0;

  /* Handle the -t switch, which specifies filename to use as terminal */
  {
    char *term;
    if (argmatch (argv, argc, "-t", "--terminal", 4, &term, &skip_args))
      {
	int result;
	close (0);
	close (1);
	result = open (term, O_RDWR, 2 );
	if (result < 0)
	  {
	    char *errstring = strerror (errno);
	    fprintf (stderr, "emacs: %s: %s\n", term, errstring);
	    exit (1);
	  }
	dup (0);
	if (! isatty (0))
	  {
	    fprintf (stderr, "emacs: %s: not a tty\n", term);
	    exit (1);
	  }
	fprintf (stderr, "Using %s\n", term);
#ifdef HAVE_WINDOW_SYSTEM
	inhibit_window_system = 1; /* -t => -nw */
#endif
      }
  }
  if (argmatch (argv, argc, "-nw", "--no-windows", 6, NULL, &skip_args))
    inhibit_window_system = 1;

  /* Handle the -batch switch, which means don't do interactive display.  */
  noninteractive = 0;
  if (argmatch (argv, argc, "-batch", "--batch", 5, NULL, &skip_args))
    noninteractive = 1;

  /* Handle the --help option, which gives a usage message..  */
  if (argmatch (argv, argc, "-help", "--help", 3, NULL, &skip_args))
    {
      printf ("\
Usage: %s [-t term] [--terminal term]  [-nw] [--no-windows]  [--batch]\n\
      [-q] [--no-init-file]  [-u user] [--user user]  [--debug-init]\n\
      [--version] [--no-site-file]\n\
      [-f func] [--funcall func]  [-l file] [--load file]  [--insert file]\n\
      [+linenum] file-to-visit  [--kill]\n\
Report bugs to bug-gnu-emacs@prep.ai.mit.edu.  First, please see\n\
the Bugs section of the Emacs manual or the file BUGS.", argv[0]);
      exit (0);
    }

#ifdef HAVE_X_WINDOWS
  /* Stupid kludge to catch command-line display spec.  We can't
     handle this argument entirely in window system dependent code
     because we don't even know which window system dependent code
     to run until we've recognized this argument.  */
  {
    char *displayname = 0;
    int i;
    int count_before = skip_args;

    if (argmatch (argv, argc, "-d", "--display", 3, &displayname, &skip_args))
      display_arg = 1;
    else if (argmatch (argv, argc, "-display", 0, 3, &displayname, &skip_args))
      display_arg = 1;

    /* If we have the form --display=NAME,
       convert it into  -d name.
       This requires inserting a new element into argv.  */
    if (displayname != 0 && skip_args - count_before == 1)
      {
	char **new = (char **) xmalloc (sizeof (char *) * (argc + 2));
	int j;

	for (j = 0; j < count_before + 1; j++)
	  new[j] = argv[j];
	new[count_before + 1] = "-d";
	new[count_before + 2] = displayname;
	for (j = count_before + 2; j <argc; j++)
	  new[j + 1] = argv[j];
	argv = new;
	argc++;
      }
    /* Change --display to -d, when its arg is separate.  */
    else if (displayname != 0 && skip_args > count_before
	     && argv[count_before + 1][1] == '-')
      argv[count_before + 1] = "-d";

    /* Don't actually discard this arg.  */
    skip_args = count_before;
  }
#endif

  if (! noninteractive)
    {
#ifdef BSD_PGRPS
      if (initialized)
	{
	  inherited_pgroup = EMACS_GETPGRP (0);
	  setpgrp (0, getpid ());
	}
#else
#if defined (USG5) && defined (INTERRUPT_INPUT)
      setpgrp ();
#endif
#endif
    }

#ifdef POSIX_SIGNALS
  init_signals ();
#endif

  /* Don't catch SIGHUP if dumping.  */
  if (1
#ifndef CANNOT_DUMP
      && initialized
#endif
      )
    {
      sigblock (sigmask (SIGHUP));
      /* In --batch mode, don't catch SIGHUP if already ignored.
	 That makes nohup work.  */
      if (! noninteractive
	  || signal (SIGHUP, SIG_IGN) != SIG_IGN)
	signal (SIGHUP, fatal_error_signal);
      sigunblock (sigmask (SIGHUP));
    }

  if (
#ifndef CANNOT_DUMP
      ! noninteractive || initialized
#else
      1
#endif
      )
    {
      /* Don't catch these signals in batch mode if dumping.
	 On some machines, this sets static data that would make
	 signal fail to work right when the dumped Emacs is run.  */
      signal (SIGQUIT, fatal_error_signal);
      signal (SIGILL, fatal_error_signal);
      signal (SIGTRAP, fatal_error_signal);
#ifdef SIGABRT
      signal (SIGABRT, fatal_error_signal);
#endif
#ifdef SIGHWE
      signal (SIGHWE, fatal_error_signal);
#endif
#ifdef SIGPRE
      signal (SIGPRE, fatal_error_signal);
#endif
#ifdef SIGORE
      signal (SIGORE, fatal_error_signal);
#endif
#ifdef SIGUME
      signal (SIGUME, fatal_error_signal);
#endif
#ifdef SIGDLK
      signal (SIGDLK, fatal_error_signal);
#endif
#ifdef SIGCPULIM
      signal (SIGCPULIM, fatal_error_signal);
#endif
#ifdef SIGIOT
      /* This is missing on some systems - OS/2, for example.  */
      signal (SIGIOT, fatal_error_signal);
#endif
#ifdef SIGEMT
      signal (SIGEMT, fatal_error_signal);
#endif
      signal (SIGFPE, fatal_error_signal);
#ifdef SIGBUS
      signal (SIGBUS, fatal_error_signal);
#endif
      signal (SIGSEGV, fatal_error_signal);
#ifdef SIGSYS
      signal (SIGSYS, fatal_error_signal);
#endif
      signal (SIGTERM, fatal_error_signal);
#ifdef SIGXCPU
      signal (SIGXCPU, fatal_error_signal);
#endif
#ifdef SIGXFSZ
      signal (SIGXFSZ, fatal_error_signal);
#endif /* SIGXFSZ */

#ifdef SIGDANGER
      /* This just means available memory is getting low.  */
      signal (SIGDANGER, memory_warning_signal);
#endif

#ifdef AIX
/* 20 is SIGCHLD, 21 is SIGTTIN, 22 is SIGTTOU.  */
      signal (SIGXCPU, fatal_error_signal);
#ifndef _I386
      signal (SIGIOINT, fatal_error_signal);
#endif
      signal (SIGGRANT, fatal_error_signal);
      signal (SIGRETRACT, fatal_error_signal);
      signal (SIGSOUND, fatal_error_signal);
      signal (SIGMSG, fatal_error_signal);
#endif /* AIX */
    }

  noninteractive1 = noninteractive;

/* Perform basic initializations (not merely interning symbols) */

  if (!initialized)
    {
      init_alloc_once ();
      init_obarray ();
      init_eval_once ();
      init_charset_once ();
      init_coding_once ();
      init_syntax_once ();	/* Create standard syntax table.  */
      init_category_once ();	/* Create standard category table.  */
		      /* Must be done before init_buffer */
      init_casetab_once ();
      init_buffer_once ();	/* Create buffer table and some buffers */
      init_minibuf_once ();	/* Create list of minibuffers */
			      /* Must precede init_window_once */
      init_window_once ();	/* Init the window system */
    }

  init_alloc ();
  init_eval ();
  init_data ();
  running_asynch_code = 0;

#ifdef MSDOS
  /* Call early 'cause init_environment needs it.  */
  init_dosfns ();
  /* Set defaults for several environment variables.  */
  if (initialized)
    init_environment (argc, argv, skip_args);
  else
    tzset ();
#endif /* MSDOS */

#ifdef WINDOWSNT
  /* Initialize environment from registry settings.  */
  init_environment ();
  init_ntproc ();	/* must precede init_editfns */
#endif

  /* egetenv is a pretty low-level facility, which may get called in
     many circumstances; it seems flimsy to put off initializing it
     until calling init_callproc.  */
  set_process_environment ();
  /* AIX crashes are reported in system versions 3.2.3 and 3.2.4
     if this is not done.  Do it after set_process_environment so that we
     don't pollute Vprocess_environment.  */
#ifdef AIX
  putenv ("LANG=C");
#endif

  init_buffer ();	/* Init default directory of main buffer */

  init_callproc_1 ();	/* Must precede init_cmdargs and init_sys_modes.  */
  init_cmdargs (argc, argv, skip_args);	/* Must precede init_lread.  */

  if (initialized)
    {
      /* Erase any pre-dump messages in the message log, to avoid confusion */
      Lisp_Object old_log_max;
      old_log_max = Vmessage_log_max;
      XSETFASTINT (Vmessage_log_max, 0);
      message_dolog ("", 0, 1);
      Vmessage_log_max = old_log_max;
    }

  init_callproc ();	/* Must follow init_cmdargs but not init_sys_modes.  */
  init_lread ();

  if (!noninteractive)
    {
#ifdef VMS
      init_vms_input ();/* init_display calls get_frame_size, that needs this */
#endif /* VMS */
      init_display ();	/* Determine terminal type.  init_sys_modes uses results */
    }
  init_keyboard ();	/* This too must precede init_sys_modes */
#ifdef VMS
  init_vmsproc ();	/* And this too. */
#endif /* VMS */
  init_sys_modes ();	/* Init system terminal modes (RAW or CBREAK, etc.) */
  init_xdisp ();
  init_macros ();
  init_editfns ();
#ifdef LISP_FLOAT_TYPE
  init_floatfns ();
#endif
#ifdef VMS
  init_vmsfns ();
#endif /* VMS */
  init_process ();
#ifdef CLASH_DETECTION
  init_filelock ();
#endif /* CLASH_DETECTION */

/* Intern the names of all standard functions and variables; define standard keys */

  if (!initialized)
    {
      /* The basic levels of Lisp must come first */
      /* And data must come first of all
	 for the sake of symbols like error-message */
      syms_of_data ();
      syms_of_alloc ();
      syms_of_lread ();
      syms_of_print ();
      syms_of_eval ();
      syms_of_fns ();
      syms_of_floatfns ();

      syms_of_abbrev ();
      syms_of_buffer ();
      syms_of_bytecode ();
      syms_of_callint ();
      syms_of_casefiddle ();
      syms_of_casetab ();
      syms_of_callproc ();
      syms_of_category ();
      syms_of_ccl ();
      syms_of_charset ();
      syms_of_cmds ();
#ifndef NO_DIR_LIBRARY
      syms_of_dired ();
#endif /* not NO_DIR_LIBRARY */
      syms_of_display ();
      syms_of_doc ();
      syms_of_editfns ();
      syms_of_emacs ();
      syms_of_fileio ();
      syms_of_coding ();	/* This should be after syms_of_fileio.  */
#ifdef CLASH_DETECTION
      syms_of_filelock ();
#endif /* CLASH_DETECTION */
      syms_of_indent ();
      syms_of_insdel ();
      syms_of_keyboard ();
      syms_of_keymap ();
      syms_of_macros ();
      syms_of_marker ();
      syms_of_minibuf ();
      syms_of_mocklisp ();
      syms_of_process ();
      syms_of_search ();
      syms_of_frame ();
      syms_of_syntax ();
      syms_of_term ();
      syms_of_undo ();

      /* Only defined if Emacs is compiled with USE_TEXT_PROPERTIES */
      syms_of_textprop ();
#ifdef VMS
      syms_of_vmsproc ();
#endif /* VMS */
#ifdef WINDOWSNT
      syms_of_ntproc ();
#endif /* WINDOWSNT */
      syms_of_window ();
      syms_of_xdisp ();
#ifdef HAVE_X_WINDOWS
      syms_of_xterm ();
      syms_of_xfns ();
      syms_of_xfaces ();
      syms_of_fontset ();
#ifdef HAVE_X11
      syms_of_xselect ();
#endif
#endif /* HAVE_X_WINDOWS */

#if defined (MSDOS) && !defined (HAVE_X_WINDOWS)
      syms_of_xfaces ();
#endif

#ifndef HAVE_NTGUI
      syms_of_xmenu ();
#endif

#ifdef HAVE_NTGUI
      syms_of_w32term ();
      syms_of_w32fns ();
      syms_of_w32faces ();
      syms_of_w32select ();
      syms_of_w32menu ();
#endif /* HAVE_NTGUI */

#ifdef SYMS_SYSTEM
      SYMS_SYSTEM;
#endif

#ifdef SYMS_MACHINE
      SYMS_MACHINE;
#endif

      keys_of_casefiddle ();
      keys_of_cmds ();
      keys_of_buffer ();
      keys_of_keyboard ();
      keys_of_keymap ();
      keys_of_macros ();
      keys_of_minibuf ();
      keys_of_window ();
      keys_of_frame ();
    }

  if (!initialized)
    {
      char *file;
      /* Handle -l loadup-and-dump, args passed by Makefile. */
      if (argmatch (argv, argc, "-l", "--load", 3, &file, &skip_args))
	Vtop_level = Fcons (intern ("load"),
			    Fcons (build_string (file), Qnil));
#ifdef CANNOT_DUMP
      /* Unless next switch is -nl, load "loadup.el" first thing.  */
      if (!argmatch (argv, argc, "-nl", "--no-loadup", 6, NULL, &skip_args))
	Vtop_level = Fcons (intern ("load"),
			    Fcons (build_string ("loadup.el"), Qnil));
#endif /* CANNOT_DUMP */
    }

  if (initialized)
    {
#ifdef HAVE_TZSET
      {
	/* If the execution TZ happens to be the same as the dump TZ,
	   change it to some other value and then change it back,
	   to force the underlying implementation to reload the TZ info.
	   This is needed on implementations that load TZ info from files,
	   since the TZ file contents may differ between dump and execution.  */
	char *tz = getenv ("TZ");
	if (tz && !strcmp (tz, dump_tz))
	  {
	    ++*tz;
	    tzset ();
	    --*tz;
	  }
      }
#endif
    }

  initialized = 1;

#ifdef LOCALTIME_CACHE
  /* Some versions of localtime have a bug.  They cache the value of the time
     zone rather than looking it up every time.  Since localtime() is
     called to bolt the undumping time into the undumped emacs, this
     results in localtime ignoring the TZ environment variable.
     This flushes the new TZ value into localtime. */
  tzset ();
#endif /* defined (LOCALTIME_CACHE) */

  /* Enter editor command loop.  This never returns.  */
  Frecursive_edit ();
  /* NOTREACHED */
}

/* Sort the args so we can find the most important ones
   at the beginning of argv.  */

/* First, here's a table of all the standard options.  */

struct standard_args
{
  char *name;
  char *longname;
  int priority;
  int nargs;
};

struct standard_args standard_args[] =
{
  { "-version", "--version", 110, 0 },
  { "-help", "--help", 110, 0 },
  { "-nl", "--no-shared-memory", 100, 0 },
#ifdef VMS
  { "-map", "--map-data", 100, 0 },
#endif
  { "-t", "--terminal", 90, 1 },
  { "-d", "--display", 80, 1 },
  { "-display", 0, 80, 1 },
  { "-nw", "--no-windows", 70, 0 },
  { "-batch", "--batch", 60, 0 },
  { "-q", "--no-init-file", 50, 0 },
  { "-no-init-file", 0, 50, 0 },
  { "-no-site-file", "--no-site-file", 40, 0 },
  { "-u", "--user", 30, 1 },
  { "-user", 0, 30, 1 },
  { "-debug-init", "--debug-init", 20, 0 },
  { "-i", "--icon-type", 15, 0 },
  { "-itype", 0, 15, 0 },
  { "-iconic", "--iconic", 15, 0 },
  { "-bg", "--background-color", 10, 1 },
  { "-background", 0, 10, 1 },
  { "-fg", "--foreground-color", 10, 1 },
  { "-foreground", 0, 10, 1 },
  { "-bd", "--border-color", 10, 1 },
  { "-bw", "--border-width", 10, 1 },
  { "-ib", "--internal-border", 10, 1 },
  { "-ms", "--mouse-color", 10, 1 },
  { "-cr", "--cursor-color", 10, 1 },
  { "-fn", "--font", 10, 1 },
  { "-font", 0, 10, 1 },
  { "-g", "--geometry", 10, 1 },
  { "-geometry", 0, 10, 1 },
  { "-T", "--title", 10, 1 },
  { "-title", 0, 10, 1 },
  { "-name", "--name", 10, 1 },
  { "-xrm", "--xrm", 10, 1 },
  { "-r", "--reverse-video", 5, 0 },
  { "-rv", 0, 5, 0 },
  { "-reverse", 0, 5, 0 },
  { "-hb", "--horizontal-scroll-bars", 5, 0 },
  { "-vb", "--vertical-scroll-bars", 5, 0 },
  /* These have the same priority as ordinary file name args,
     so they are not reordered with respect to those.  */
  { "-L", "--directory", 0, 1 },
  { "-directory", 0, 0, 1 },
  { "-l", "--load", 0, 1 },
  { "-load", 0, 0, 1 },
  { "-f", "--funcall", 0, 1 },
  { "-funcall", 0, 0, 1 },
  { "-eval", "--eval", 0, 1 },
  { "-find-file", "--find-file", 0, 1 },
  { "-visit", "--visit", 0, 1 },
  { "-insert", "--insert", 0, 1 },
  /* This should be processed after ordinary file name args and the like.  */
  { "-kill", "--kill", -10, 0 },
};

/* Reorder the elements of ARGV (assumed to have ARGC elements)
   so that the highest priority ones come first.
   Do not change the order of elements of equal priority.
   If an option takes an argument, keep it and its argument together.  */

static void
sort_args (argc, argv)
     int argc;
     char **argv;
{
  char **new = (char **) xmalloc (sizeof (char *) * argc);
  /* For each element of argv,
     the corresponding element of options is:
     0 for an option that takes no arguments,
     1 for an option that takes one argument, etc.
     -1 for an ordinary non-option argument.  */
  int *options = (int *) xmalloc (sizeof (int) * argc);
  int *priority = (int *) xmalloc (sizeof (int) * argc);
  int to = 1;
  int from;
  int i;
  int end_of_options = argc;

  /* Categorize all the options,
     and figure out which argv elts are option arguments.  */
  for (from = 1; from < argc; from++)
    {
      options[from] = -1;
      priority[from] = 0;
      if (argv[from][0] == '-')
	{
	  int match, thislen;
	  char *equals;

	  /* If we have found "--", don't consider
	     any more arguments as options.  */
	  if (argv[from][1] == '-')
	    {
	      /* Leave the "--", and everything following it, at the end.  */
	      for (; from < argc; from++)
		{
		  priority[from] = -100;
		  options[from] = -1;
		}
	      break;
	    }