emacs.c

/* Fully extensible Emacs, running on Unix, intended for GNU.
   Copyright (C) 1985,86,87,93,94,95,97,98,1999 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 <config.h>
#include <signal.h>
#include <errno.h>
#include <stdio.h>

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

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

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

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

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

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

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

#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 ();

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

EMACS_INT gdb_valbits = VALBITS;
EMACS_INT gdb_gctypebits = GCTYPEBITS;
EMACS_INT gdb_emacs_intbits = sizeof (EMACS_INT) * BITS_PER_CHAR;
#ifdef DATA_SEG_BITS
EMACS_INT gdb_data_seg_bits = DATA_SEG_BITS;
#else
EMACS_INT  gdb_data_seg_bits = 0;
#endif
EMACS_INT PVEC_FLAG = PSEUDOVECTOR_FLAG;

/* 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;

#ifdef SIGUSR1
/* Hooks for signal USR1 and USR2 handing */
Lisp_Object Vsignal_USR1_hook;
#ifdef SIGUSR2
Lisp_Object Vsignal_USR2_hook;
#endif 
#endif

/* Search path separator.  */
Lisp_Object Vpath_separator;

/* 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 ();
/* Non-zero if the MALLOC_CHECK_ enviroment variable was set while
   dumping.  Used to work around a bug in glibc's malloc.  */
int malloc_using_checking;
#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;

/* Current and previous system locales for messages and time.  */
Lisp_Object Vsystem_messages_locale;
Lisp_Object Vprevious_system_messages_locale;
Lisp_Object Vsystem_time_locale;
Lisp_Object Vprevious_system_time_locale;

/* 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 ();
void syms_of_emacs ();

/* 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;

#ifdef SIGUSR1
SIGTYPE
handle_USR1_signal (sig)
     int sig;
{
  struct input_event buf;

  buf.kind = user_signal;
  buf.code = 0;
  buf.frame_or_window = selected_frame;
  buf.modifiers = 0;
  buf.timestamp = 0;

  kbd_buffer_store_event (&buf);
}
#endif /* SIGUSR1 */

#ifdef SIGUSR2
SIGTYPE
handle_USR2_signal (sig)
     int sig;
{
  struct input_event buf;

  buf.kind = user_signal;
  buf.code = 1;
  buf.frame_or_window = selected_frame;
  buf.modifiers = 0;
  buf.timestamp = 0;

  kbd_buffer_store_event (&buf);
}
#endif /* SIGUSR2 */

/* 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

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

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

#ifndef ABORT_RETURN_TYPE
#define ABORT_RETURN_TYPE void
#endif

ABORT_RETURN_TYPE
abort ()
{
  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 (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
void __do_global_ctors ()
{}
void __do_global_ctors_aux ()
{}
void __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 */
void __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;
    }
}

#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 ()
{
  extern char **environ;

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

      malloc_set_state (malloc_state_ptr);
      free (malloc_state_ptr);
    }
  else
    malloc_using_checking = getenv ("MALLOC_CHECK_") != NULL;
}

void (*__malloc_initialize_hook) () = malloc_initialize_hook;

#endif /* DOUG_LEA_MALLOC */

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

#ifdef LINUX_SBRK_BUG
  __sbrk (1);
#endif

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

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

  if (argmatch (argv, argc, "-version", "--version", 3, NULL, &skip_args)
      /* We don't know the version number unless this is a dumped Emacs.
         So ignore --version otherwise.  */
      && initialized)
    {
      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) 1999 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 file 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 */

#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 int 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;

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

  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));

  /* Arrange to disable interrupt input inside malloc etc.  */
  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 */

  /* 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, "");

#ifdef EXTRA_INITIALIZE
  EXTRA_INITIALIZE;
#endif

  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)
	    {
	      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
	}
      else
	break;
    }

  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 [--batch]  [-t term] [--terminal term]\n\
      [-d display] [--display display]  [-nw] [--no-windows]\n\
      [-q] [--no-init-file]  [-u user] [--user user]  [--debug-init]\n\
      [--unibyte] [--multibyte] [--version] [--no-site-file]\n\
      [-f func] [--funcall func]  [-l file] [--load file]  [--eval expr]\n\
      [--execute expr] [--visit file] [--file file] [--insert file]\n\
      [+linenum] file-to-visit  [--kill]\n\
Report bugs to bug-gnu-emacs@gnu.org.  First, please see\n\
the Bugs section of the Emacs manual or the file BUGS.\n", argv[0]);
      exit (0);
    }

  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
    }

  init_signals ();

  /* 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 SIGUSR1
      signal (SIGUSR1, handle_USR1_signal);
#ifdef SIGUSR2
      signal (SIGUSR2, handle_USR2_signal);
#endif
#endif
#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 */
      
      /* Call syms_of_xfaces before init_window_once because that
	 function creates Vterminal_frame.  Termcap frames now use
	 faces, and the face implementation uses some symbols as
	 face names.  */
#ifndef HAVE_NTGUI
      syms_of_xfaces ();
#endif

      init_window_once ();	/* Init the window system */
      init_fileio_once ();	/* Must precede any path manipulation.  */
    }

  init_alloc ();

  if (do_initial_setlocale)
    {
      fixup_locale ();
      Vsystem_messages_locale = Vprevious_system_messages_locale;
      Vsystem_time_locale = Vprevious_system_time_locale;
    }

  init_eval ();
  init_coding ();
  init_data ();
#ifdef CLASH_DETECTION
  init_filelock ();;
#endif
  running_asynch_code = 0;

  /* Handle --unibyte and the EMACS_UNIBYTE envvar,
     but not while dumping.  */
  if (
#ifndef CANNOT_DUMP
      ! noninteractive || initialized
#else
      1
#endif
      )
    {
      int inhibit_unibyte = 0;

      /* --multibyte overrides EMACS_UNIBYTE.  */
      if (argmatch (argv, argc, "-no-unibyte", "--no-unibyte", 4, NULL, &skip_args)
	  || argmatch (argv, argc, "-multibyte", "--multibyte", 4, NULL, &skip_args))
	inhibit_unibyte = 1;

      /* --unibyte requests that we set up to do everything with single-byte
	 buffers and strings.  We need to handle this before calling
	 init_lread, init_editfns and other places that generate Lisp strings
	 from text in the environment.  */
      /* Actually this shouldn't be needed as of 20.4 in a generally
	 unibyte environment.  As handa says, environment values
	 aren't now decoded; also existing buffers are now made
	 unibyte during startup if .emacs sets unibyte.  Tested with
	 8-bit data in environment variables and /etc/passwd, setting
	 unibyte and Latin-1 in .emacs. -- Dave Love */
      if (argmatch (argv, argc, "-unibyte", "--unibyte", 4, NULL, &skip_args)
	  || argmatch (argv, argc, "-no-multibyte", "--no-multibyte", 4, NULL, &skip_args)
	  || (getenv ("EMACS_UNIBYTE") && !inhibit_unibyte))
	{
	  Lisp_Object old_log_max;
	  Lisp_Object symbol, tail;

	  symbol = intern ("default-enable-multibyte-characters");
	  Fset (symbol, Qnil);

	  if (initialized)
	    {
	      /* Erase pre-dump messages in *Messages* now so no abort.  */
	      old_log_max = Vmessage_log_max;
	      XSETFASTINT (Vmessage_log_max, 0);
	      message_dolog (""