/* Buffer manipulation primitives for GNU Emacs.
   Copyright (C) 1985, 1986, 1987, 1988, 1989, 1992, 1993, 1994
	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, 675 Mass Ave, Cambridge, MA 02139, USA.  */


#include "config.h"
#include "intl.h"

#include <stdio.h>		/* For sprintf */
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>

#ifndef MAXPATHLEN
/* in 4.1, param.h fails to define this. */
#define MAXPATHLEN 1024
#endif /* not MAXPATHLEN */

#include "lisp.h"
#include "window.h"
#include "faces.h"
#include "commands.h"
#include "buffer.h"
#include "symeval.h"
#include "insdel.h"
#include "screen.h"
#include "syntax.h"
#include "dispextern.h"

#include "process.h"            /* for kill_buffer_processes */

#include "blockio.h"

#include "sysdep.h"	/* for getwd */

struct buffer *current_buffer;	/* the current buffer */

/* This structure holds the default values of the buffer-local variables
   defined with DEFVAR_BUFFER_LOCAL, that have special slots in each buffer.
   The default value occupies the same slot in this structure
   as an individual buffer's value occupies in that buffer.
   Setting the default value also goes through the alist of buffers
   and stores into each buffer that does not say it has a local value.  */
Lisp_Object Vbuffer_defaults;

/* This structure marks which slots in a buffer have corresponding
   default values in buffer_defaults.
   Each such slot has a nonzero value in this structure.
   The value has only one nonzero bit.

   When a buffer has its own local value for a slot,
   the bit for that slot (found in the same slot in this structure)
   is turned on in the buffer's local_var_flags slot.

   If a slot in this structure is 0, then there is a DEFVAR_BUFFER_LOCAL
   for the slot, but there is no default value for it; the corresponding
   slot in buffer_defaults is not used except to initialise newly-created
   buffers.

   If a slot is -1, then there is a DEFVAR_BUFFER_LOCAL for it
   as well as a default value which is used to initialise newly-created
   buffers and as a reset-value when local-vars are killed.

   If a slot is -2, there is no DEFVAR_BUFFER_LOCAL for it. 
   (The slot is always local, but there's no lisp variable for it.)
   The default value is only used to initialise newly-creation buffers. 
   
   If a slot is -3, then there is no DEFVAR_BUFFER_LOCAL for it but
   there is a default which is used to initialise newly-creation
   buffers and as a reset-value when local-vars are killed.

   
   */
struct buffer buffer_local_flags;

/* This structure holds the names of symbols whose values may be
   buffer-local.  It is indexed and accessed in the same way as the above. */
static Lisp_Object Vbuffer_local_symbols;

/* Alist of all buffer names vs the buffers. */
/* This used to be a variable, but is no longer,
   to prevent lossage due to user rplac'ing this alist or its elements.
   Note that there is a per-screen copy of this as well; the screen slot
   and the global variable contain the same data, but possibly in different
   orders, so that the buffer ordering can be per-screen.
  */
Lisp_Object Vbuffer_alist;

/* Functions to call before and after each text change. */
Lisp_Object Qbefore_change_functions;
Lisp_Object Qafter_change_functions;
Lisp_Object Vbefore_change_functions;
Lisp_Object Vafter_change_functions;

/* #### Obsolete, for compatibility */
Lisp_Object Qbefore_change_function;
Lisp_Object Qafter_change_function;
Lisp_Object Vbefore_change_function;
Lisp_Object Vafter_change_function;

#if 0 /* RMSmacs */
Lisp_Object Vtransient_mark_mode;
#endif

/* t means ignore all read-only text properties.
   A list means ignore such a property if its value is a member of the list.
   Any non-nil value means ignore buffer-read-only.  */
Lisp_Object Vinhibit_read_only;

/* List of functions to call that can query about killing a buffer.
   If any of these functions returns nil, we don't kill it.  */
Lisp_Object Vkill_buffer_query_functions;

/* Non-nil means delete a buffer's auto-save file when the buffer is saved. */
Lisp_Object Vdelete_auto_save_files;

/* List of functions to call before changing an unmodified buffer.  */
Lisp_Object Vfirst_change_hook;
Lisp_Object Qfirst_change_hook;

Lisp_Object Qfundamental_mode;
Lisp_Object Qmode_class;
Lisp_Object Qpermanent_local;

Lisp_Object Qprotected_field;

Lisp_Object QSFundamental;	/* A string "Fundamental" */
Lisp_Object QSscratch;          /* "*scratch*" */
Lisp_Object Qdefault_directory;

Lisp_Object Qkill_buffer_hook;
Lisp_Object Qbuffer_file_name, Qbuffer_undo_list;

Lisp_Object Qrename_auto_save_file;

Lisp_Object Qget_file_buffer;
Lisp_Object Qchange_major_mode_hook;

/* Two thresholds controlling how much undo information to keep.  */
int undo_threshold;
int undo_high_threshold;

int find_file_compare_truenames;
int find_file_use_truenames;


static void reset_buffer_local_variables (struct buffer *);
static Lisp_Object mark_buffer (Lisp_Object, void (*) (Lisp_Object));
static void print_buffer (Lisp_Object, Lisp_Object, int);
DEFINE_LRECORD_IMPLEMENTATION ("buffer", lrecord_buffer,
                               mark_buffer, print_buffer, 0, 0,
			       sizeof (struct buffer));

#ifdef ENERGIZE
extern void mark_energize_buffer_data (struct buffer *b,
				       void (*markobj) (Lisp_Object));
#endif

static Lisp_Object
mark_buffer (Lisp_Object obj, void (*markobj) (Lisp_Object))
{
  struct buffer *buf = XBUFFER (obj);

  /* Truncate undo information. */
  buf->undo_list = truncate_undo_list (buf->undo_list,
                                       undo_threshold,
                                       undo_high_threshold);

#define MARKED_SLOT(x) ((markobj) (buf->x));
#include "bufslots.h"
#undef MARKED_SLOT

#ifdef ENERGIZE
  mark_energize_buffer_data (XBUFFER (obj), markobj);
#endif

  return (Qnil);
}

static void
print_buffer (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
{
  struct buffer *b = XBUFFER (obj);

  if (print_readably) 
    {
      if (NILP (b->name))
	error (GETTEXT ("printing unreadable object #<killed buffer>"));
      else
	error (GETTEXT ("printing unreadable object #<buffer %s>"), 
	       XSTRING (b->name)->data);
    }
  else if (NILP (b->name))
    write_string_1 (GETTEXT ("#<killed buffer>"), -1, printcharfun);
  else if (escapeflag)
    {
      write_string_1 (GETTEXT ("#<buffer "), -1, printcharfun);
      print_internal (b->name, printcharfun, 1);
      write_string_1 (">", -1, printcharfun);
    }
  else
    {
      print_internal (b->name, printcharfun, 0);
    }
}

#if 0
static int
sizeof_buffer (void *h)
{
  struct buffer *b = h;
  int size = sizeof (*b);
  size += (BUF_Z (b) - BUF_BEG (b));
  size += (BUF_GAP_SIZE (b));
  return (size);
}
#endif
    
  

DEFUN ("bufferp", Fbufferp, Sbufferp, 1, 1, 0,
  "T if OBJECT is an editor buffer.")
  (object)
     Lisp_Object object;
{
  if (BUFFERP (object))
    return Qt;
  return Qnil;
}


static void
nsberror (spec)
     Lisp_Object spec;
{
  if (STRINGP (spec))
    error (GETTEXT ("No buffer named %s"), XSTRING (spec)->data);
  signal_error (Qerror,
		list2 (build_string (GETTEXT ("Invalid buffer argument")),
		       spec));
}

DEFUN ("buffer-list", Fbuffer_list, Sbuffer_list, 0, 1, 0,
  "Return a list of all existing live buffers.\n\
The order is specific to the selected screen; if the optional SCREEN\n\
argument is provided, the ordering for that screen is returned instead.\n\
If the SCREEN argument is t, then the global (non-screen) ordering is\n\
returned instead.")
  (screen)
  Lisp_Object screen;
{
  Lisp_Object list;
  if (EQ (screen, Qt))
    list = Vbuffer_alist;
  else if (NILP (screen))
    list = selected_screen->buffer_alist;
  else
    {
      CHECK_SCREEN (screen, 0);
      list = XSCREEN (screen)->buffer_alist;
    }
  return Fmapcar (Qcdr, list);
}

Lisp_Object
get_buffer (Lisp_Object name, int error_if_deleted_or_does_not_exist)
{
  Lisp_Object buf;

  if (BUFFERP (name))
    {
      if (NILP (XBUFFER (name)->name))
        {
          if (error_if_deleted_or_does_not_exist)
            nsberror (name);
          return (Qnil);
        }
      return name;
    }
  else
    {
      CHECK_STRING (name, 0);
      buf = Fcdr (Fassoc (name, Vbuffer_alist));
      if (NILP (buf) && error_if_deleted_or_does_not_exist)
	nsberror (name);
      return (buf);
    }
}

DEFUN ("get-buffer", Fget_buffer, Sget_buffer, 1, 1, 0,
  "Return the buffer named NAME (a string).\n\
If there is no live buffer named NAME, return nil.\n\
NAME may also be a buffer; if so, the value is that buffer.")
  (name)
     register Lisp_Object name;
{
  /* #### This might return a dead buffer.  This is gross.  This is
     called FSF compatibility. */
  if (BUFFERP (name))
    return name;
  return (get_buffer (name, 0));
}


DEFUN ("get-file-buffer", Fget_file_buffer, Sget_file_buffer, 1, 1, 0,
  "Return the buffer visiting file FILENAME (a string).\n\
If there is no such live buffer, return nil.")
  (filename)
     Lisp_Object filename;
{
  register Lisp_Object tail, buf, tem;
  struct gcpro gcpro1;

  GCPRO1 (filename);
  CHECK_STRING (filename, 0);
  filename = Fexpand_file_name (filename, Qnil);
  UNGCPRO;
  {
    /* If the file name has special constructs in it,
       call the corresponding file handler.  */
    Lisp_Object handler = Ffind_file_name_handler (filename, Qget_file_buffer);
    if (!NILP (handler))
      return call2 (handler, Qget_file_buffer, filename);
  }

  if (find_file_compare_truenames || find_file_use_truenames)
    {
      struct gcpro gcpro1, gcpro2, gcpro3;
      Lisp_Object fn = Qnil;
      Lisp_Object dn = Qnil;

      GCPRO3 (fn, dn, filename);
      fn = Ffile_truename (filename, Qnil);
      if (NILP (fn))
	{
	  dn = Ffile_name_directory (filename);
	  fn = Ffile_truename (dn, Qnil);
	  if (! NILP (fn)) dn = fn;
	  fn = Fexpand_file_name (Ffile_name_nondirectory (filename), dn);
	}
      filename = fn;
      UNGCPRO;
    }

  for (tail = Vbuffer_alist; CONSP (tail); tail = XCONS (tail)->cdr)
    {
      buf = Fcdr (XCONS (tail)->car);
      if (!BUFFERP (buf)) continue;
      if (!STRINGP (XBUFFER (buf)->filename)) continue;
      tem = Fstring_equal (filename,
			   (find_file_compare_truenames
			    ? XBUFFER (buf)->truename
			    : XBUFFER (buf)->filename));
      if (!NILP (tem))
	return buf;
    }
  return Qnil;
}


static void
push_buffer_alist (name, buf)
     Lisp_Object name, buf;
{
  Lisp_Object cons = Fcons (name, buf);
  Lisp_Object rest;
  Vbuffer_alist = nconc2 (Vbuffer_alist, Fcons (cons, Qnil));
#ifdef MULTI_SCREEN
  for (rest = Vscreen_list; !NILP (rest); rest = XCONS (rest)->cdr)
    {
      struct screen *s;
      if (!SCREENP (XCONS (rest)->car))
	abort ();
      s = XSCREEN (XCONS (rest)->car);
      s->buffer_alist = nconc2 (s->buffer_alist, Fcons (cons, Qnil));
    }
#endif
}

static void
delete_from_buffer_alist (buf)
     Lisp_Object buf;
{
  Lisp_Object cons = Frassq (buf, Vbuffer_alist);
  Lisp_Object rest;
  if (NILP (cons))
    return; /* abort() ? */
  Vbuffer_alist = delq_no_quit (cons, Vbuffer_alist);
#ifdef MULTI_SCREEN
  for (rest = Vscreen_list; !NILP (rest); rest = XCONS (rest)->cdr)
    {
      struct screen *s;
      if (!SCREENP (XCONS (rest)->car))
	abort ();
      s = XSCREEN (XCONS (rest)->car);
      s->buffer_alist = delq_no_quit (cons, s->buffer_alist);
    }
#endif
}


DEFUN ("get-buffer-create", Fget_buffer_create, Sget_buffer_create, 1, 1, 0,
  "Return the buffer named NAME, or create such a buffer and return it.\n\
A new buffer is created if there is no live buffer named NAME.\n\
If NAME starts with a space, the new buffer does not keep undo information.\n\
If NAME is a buffer instead of a string, then it is the value returned.\n\
The value is never nil.")  
  (name)
     register Lisp_Object name;
{
  Lisp_Object buf, function, tem;
  int speccount = specpdl_depth ();
  register struct buffer *b;

  buf = Fget_buffer (name);
  if (!NILP (buf))
    return buf;

  if (string_length (XSTRING (name)) == 0)
    error ("Empty string for buffer name is not allowed");

  b = alloc_lcrecord (sizeof (struct buffer), lrecord_buffer);
  XSETR (buf, Lisp_Buffer, b);
  {
    /* Default everything to Vbuffer_defaults,
       remembering to preserve allocation/GC info */
    struct lcrecord_header save;
    save = b->header;
    *b = *XBUFFER (Vbuffer_defaults);
    b->header = save;
  }
  reset_buffer_local_variables (b);
  b->directory = ((current_buffer) ? current_buffer->directory : Qnil);

  BUF_GAP_SIZE (b) = 20;
  BLOCK_INPUT;
  (void) BUFFER_ALLOC (BUF_BEG_ADDR (b), BUF_GAP_SIZE (b));
  UNBLOCK_INPUT;
  if (! BUF_BEG_ADDR (b))
    memory_full ();

  /*BUF_PT (b) = 1;*/	/* no longer an lvalue */
  b->text.pt = 1;
  BUF_GPT (b) = 1;
  BUF_BEGV (b) = 1;
  BUF_ZV (b) = 1;
  BUF_Z (b) = 1;
  BUF_MODIFF (b) = 1;
  BUF_FACECHANGE (b) = 1;
  BUF_MARGINCHANGE (b) = 1;

  b->last_window_start = 1;

  b->name = name;
  if (XSTRING (name)->data[0] != ' ')
    b->undo_list = Qnil;
  else
    b->undo_list = Qt;

  /* initialize the extent cache */
  b->cached_stack = 0;
  init_buffer_cached_stack (b);

  /* Put this in the alist of all live buffers.  */
  push_buffer_alist (name, buf);

  b->mark = Fmake_marker ();
  b->markers = 0;
  b->point_marker = Fmake_marker ();
  Fset_marker (b->point_marker, make_number (1), buf);

  function = XBUFFER (Vbuffer_defaults)->major_mode;
  if (NILP (function))
    {
      tem = Fget (current_buffer->major_mode, Qmode_class, Qnil);
      if (EQ (tem, Qnil))
	function = current_buffer->major_mode;
    }

  if (NILP (function) || EQ (function, Qfundamental_mode))
    return buf;

  /* To select a nonfundamental mode,
     select the buffer temporarily and then call the mode function. */

  record_unwind_protect (save_excursion_restore, save_excursion_save ());

  Fset_buffer (buf);
  call0 (function);

  return unbind_to (speccount, buf);
}


static void
reset_buffer_local_variables (struct buffer *b)
{
  struct buffer *def = XBUFFER (Vbuffer_defaults);

  b->local_var_flags = 0;
  /* For each slot that has a default value,
     copy that into the slot.  */
#define MARKED_SLOT(slot) \
  { int mask = XINT (buffer_local_flags.slot); \
    if (mask > 0 || mask == -1 || mask == -3) \
      b->slot = def->slot; \
  }
#include "bufslots.h"
#undef MARKED_SLOT
}


/*
 * The margins are properties of buffers, not windows.  If the buffer
 * is displayed on multiple windows then the margin will be on
 * multiple windows.
 */
DEFUN ("set-buffer-left-margin-width", Fset_buffer_left_margin_width,
       Sset_buffer_left_margin_width, 1, 2, 0,
  "Make the left outside margin of buffer BUFFER be NUM characters wide.\n\
If BUFFER is nil, the current buffer is assumed.  If width is NIL then\n\
any screen default will be used.  To force the buffer margin width to be 0\n\
set it to 0.")
  (width, buffer)
    Lisp_Object width, buffer;
{
  struct buffer *buf;

  if (!NILP (width))
    CHECK_FIXNUM (width, 0);

  if (NILP (buffer))
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER(buffer);
    }

  if ((NILP (width) && !NILP (buf->left_outside_margin_width))
      || (FIXNUMP (width) && !EQ (buf->left_outside_margin_width, width)))
    {
      buf->left_outside_margin_width = width;
      buf->text.margin_change = 1;
    }

  return (width);
}

DEFUN ("set-buffer-right-margin-width", Fset_buffer_right_margin_width,
       Sset_buffer_right_margin_width, 1, 2, 0,
  "Make the right outside margin of buffer BUFFER be NUM characters wide.\n\
If BUFFER is nil, the current buffer is assumed.  If width is nil then\n\
any screen default will be used.  To force the buffer margin width to be 0\n\
set it to 0.")
  (width, buffer)
    Lisp_Object width, buffer;
{
  struct buffer *buf;

  if (!NILP (width))
    CHECK_FIXNUM (width, 0);

  if (NILP (buffer))
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER(buffer);
    }

  if ((NILP (width) && !NILP (buf->right_outside_margin_width))
      || (FIXNUMP (width) && !EQ (buf->right_outside_margin_width, width)))
    {
      buf->right_outside_margin_width = width;
      buf->text.margin_change = 1;
    }

  return (width);
}

DEFUN ("buffer-left-margin-width", Fbuffer_left_margin_width,
       Sbuffer_left_margin_width, 0, 1, 0,
  "Return the width in characters of the left outside margin of\n\
buffer BUFFER.  If BUFFER is nil, the current buffer is assumed.")
  (buffer)
    Lisp_Object buffer;
{
  struct buffer *buf;

  if (NILP (buffer))
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER(buffer);
    }

  return (buf->left_outside_margin_width);
}

DEFUN ("buffer-right-margin-width", Fbuffer_right_margin_width,
       Sbuffer_right_margin_width, 0, 1, 0,
  "Return the width in characters of the right outside margin of\n\
buffer BUFFER.  If BUFFER is nil, the current buffer is assumed.")
  (buffer)
    Lisp_Object buffer;
{
  struct buffer *buf;

  if (NILP (buffer))
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER(buffer);
    }

  return (buf->right_outside_margin_width);
}

/* We split this away from generate-new-buffer, because rename-buffer
   and set-visited-file-name ought to be able to use this to really
   rename the buffer properly.  */

DEFUN ("generate-new-buffer-name", Fgenerate_new_buffer_name, Sgenerate_new_buffer_name,
  1, 2, 0,
  "Return a string that is the name of no existing buffer based on NAME.\n\
If there is no live buffer named NAME, then return NAME.\n\
Otherwise modify name by appending `<NUMBER>', incrementing NUMBER\n\
until an unused name is found, and then return that name.\n\
Optional second argument IGNORE specifies a name that is okay to use\n\
\(if it is in the sequence to be tried)\n\
even if a buffer with that name exists.")
 (name, ignore)
     Lisp_Object name, ignore;
{
  register Lisp_Object gentemp, tem;
  int count;
  char number[10];

  CHECK_STRING (name, 0);

  tem = Fget_buffer (name);
  if (NILP (tem))
    return (name);

  count = 1;
  while (1)
    {
      sprintf (number, "<%d>", ++count);
      gentemp = concat2 (name, build_string (number));
      if (!NILP (ignore))
        {
          tem = Fstring_equal (gentemp, ignore);
          if (!NILP (tem))
            return gentemp;
        }
      tem = Fget_buffer (gentemp);
      if (NILP (tem))
	return (gentemp);
    }
}


DEFUN ("buffer-name", Fbuffer_name, Sbuffer_name, 0, 1, 0,
  "Return the name of BUFFER, as a string.\n\
With no argument or nil as argument, return the name of the current buffer.")
  (buffer)
     register Lisp_Object buffer;
{
  if (NILP (buffer))
    return current_buffer->name;
  CHECK_BUFFER (buffer, 0);
  return XBUFFER (buffer)->name;
}

DEFUN ("buffer-file-name", Fbuffer_file_name, Sbuffer_file_name, 0, 1, 0,
  "Return name of file BUFFER is visiting, or nil if none.\n\
No argument or nil as argument means use the current buffer.")
  (buffer)
     register Lisp_Object buffer;
{
  if (NILP (buffer))
    return current_buffer->filename;
  CHECK_BUFFER (buffer, 0);
  return XBUFFER (buffer)->filename;
}

DEFUN ("buffer-local-variables", Fbuffer_local_variables,
  Sbuffer_local_variables, 0, 1, 0,
  "Return an alist of variables that are buffer-local in BUFFER.\n\
Most elements look like (SYMBOL . VALUE), describing one variable.\n\
For a symbol that is locally unbound, just the symbol appears in the value.\n\
Note that storing new VALUEs in these elements doesn't change the variables.\n\
No argument or nil as argument means use current buffer as BUFFER.")
  (buffer)
     register Lisp_Object buffer;
{
  struct buffer *buf;
  Lisp_Object result = Qnil;

  if (NILP (buffer))
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER (buffer);
    }

  {
    /* Reference each variable in the alist in our current buffer.
       If inquiring about the current buffer, this gets the current values,
       so store them into the alist so the alist is up to date.
       If inquiring about some other buffer, this swaps out any values
       for that buffer, making the alist up to date automatically.  */
    Lisp_Object tail;
    for (tail = buf->local_var_alist; CONSP (tail); tail = XCONS (tail)->cdr)
      {
        Lisp_Object elt = XCONS (tail)->car;
        Lisp_Object val = ((buf == current_buffer)
                           ? find_symbol_value (XCONS (elt)->car)
                           : XCONS (elt)->cdr);

	/* If symbol is unbound, put just the symbol in the list.  */
	if (EQ (val, Qunbound))
	  result = Fcons (XCONS (elt)->car, result);
	/* Otherwise, put (symbol . value) in the list.  */
	else
	  result = Fcons (Fcons (XCONS (elt)->car, val), result);
      }
  }

  /* Add on all the variables stored in special slots.  */
  {
    struct buffer *syms = XBUFFER (Vbuffer_local_symbols);
#define MARKED_SLOT(slot) \
    { int mask = XINT (buffer_local_flags.slot); \
      if (mask == 0 || mask == -1 \
	  || ((mask > 0) && (buf->local_var_flags & mask))) \
        result = Fcons (Fcons (syms->slot, buf->slot), result); \
    }
#include "bufslots.h"
#undef MARKED_SLOT
  }
  return (result);
}

DEFUN ("buffer-dedicated-screen", Fbuffer_dedicated_screen, Sbuffer_dedicated_screen,
       0, 1, 0,
       "Return the screen dedicated to this BUFFER, or nil if there is none.\n\
No argument or nil as argument means use current buffer as BUFFER.")
  (buffer)
     register Lisp_Object buffer;
{
  register struct buffer *buf;
  if (NILP (buffer))
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER (buffer);
    }

  return buf->dedicated_screen;
}

DEFUN ("set-buffer-dedicated-screen", Fset_buffer_dedicated_screen,
       Sset_buffer_dedicated_screen,
       2, 2, 0,
       "For this BUFFER, set the SCREEN dedicated to it.\n\
SCREEN must be a screen or nil.")
  (buffer, screen)
     register Lisp_Object buffer, screen;
{
  register struct buffer *buf;
  if (NILP (buffer))
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER (buffer);
    }

  if (!NILP (screen))
    CHECK_SCREEN (screen, 0);

  return buf->dedicated_screen = screen;
}



DEFUN ("buffer-modified-p", Fbuffer_modified_p, Sbuffer_modified_p,
  0, 1, 0,
  "Return t if BUFFER was modified since its file was last read or saved.\n\
No argument or nil as argument means use current buffer as BUFFER.")
  (buffer)
     register Lisp_Object buffer;
{
  register struct buffer *buf;
  if (NILP (buffer))
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER (buffer);
    }

  return buf->save_modified < BUF_MODIFF (buf) ? Qt : Qnil;
}

DEFUN ("set-buffer-modified-p", Fset_buffer_modified_p, Sset_buffer_modified_p,
  1, 1, 0,
  "Mark current buffer as modified or unmodified according to FLAG.\n\
A non-nil FLAG means mark the buffer modified.")
  (flag)
     register Lisp_Object flag;
{
  register int already;
  register Lisp_Object fn;
#ifdef ENERGIZE
  Lisp_Object starting_flag = 
    (current_buffer->save_modified < BUF_MODIFF (current_buffer))?Qt:Qnil;
  Lisp_Object argument_flag = (NILP (flag))?Qnil:Qt;
#endif  

#ifdef CLASH_DETECTION
  /* If buffer becoming modified, lock the file.
     If buffer becoming unmodified, unlock the file.  */

  fn = current_buffer->filename;
  if (!NILP (fn))
    {
      already = current_buffer->save_modified < MODIFF;
      if (!already && !NILP (flag))
	lock_file (fn);
      else if (already && NILP (flag))
	unlock_file (fn);
    }
#endif                          /* CLASH_DETECTION */

  current_buffer->save_modified = NILP (flag) ? MODIFF : 0;
  redraw_mode_line++;

#ifdef ENERGIZE
  /* don't send any notification if we are "setting" the modification bit
     to be the same as it already was */
  if (!EQ (starting_flag, argument_flag))
    {
      extern Lisp_Object Qenergize_buffer_modified_hook;
      run_hook_with_args (Qenergize_buffer_modified_hook, 3,
			  flag, make_number (BEG), make_number (Z));
    }
#endif /* ENERGIZE */

  return flag;
}

DEFUN ("buffer-modified-tick", Fbuffer_modified_tick, Sbuffer_modified_tick,
  0, 1, 0,
  "Return BUFFER's tick counter, incremented for each change in text.\n\
Each buffer has a tick counter which is incremented each time the text in\n\
that buffer is changed.  It wraps around occasionally.\n\
No argument or nil as argument means use current buffer as BUFFER.")
  (buffer)
     register Lisp_Object buffer;
{
  register struct buffer *buf;
  if (NILP (buffer))
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER (buffer);
    }

  return make_number (BUF_MODIFF (buf));
}

DEFUN ("rename-buffer", Frename_buffer, Srename_buffer, 1, 2,
       "sRename buffer (to new name): \nP",
  "Change current buffer's name to NEWNAME (a string).\n\
If second arg UNIQUE is nil or omitted, it is an error if a\n\
buffer named NEWNAME already exists.\n\
If UNIQUE is non-nil, come up with a new name using\n\
`generate-new-buffer-name'.\n\
Interactively, one can set UNIQUE with a prefix argument.\n\
Returns the name we actually gave the buffer.\n\
This does not change the name of the visited file (if any).")
  (name, unique)
     register Lisp_Object name, unique;
{
  Lisp_Object tem, buf;

  CHECK_STRING (name, 0);
  tem = Fget_buffer (name);
  if (XBUFFER (tem) == current_buffer)
    return (current_buffer->name);
  if (!NILP (tem))
    {
      if (!NILP (unique))
	name = Fgenerate_new_buffer_name (name, current_buffer->name);
      else
	error (GETTEXT ("Buffer name \"%s\" is in use"), XSTRING (name)->data);
    }

  current_buffer->name = name;

  /* Catch redisplay's attention.  Unless we do this, the mode lines for
     any windows displaying current_buffer will stay unchanged.  */
  redraw_mode_line++;

  buf = Fcurrent_buffer ();

  /* The aconses in the Vbuffer_alist are shared with screen->buffer_alist,
     so this will change it in the per-screen ordering as well. */
  Fsetcar (Frassq (buf, Vbuffer_alist), name);
  if (NILP (current_buffer->filename)
      && !NILP (current_buffer->auto_save_file_name))
    call0 (Qrename_auto_save_file);
  return (name);
}

DEFUN ("other-buffer", Fother_buffer, Sother_buffer, 0, 2, 0,
  "Return most recently selected buffer other than BUFFER.\n\
Buffers not visible in windows are preferred to visible buffers.\n\
If no other buffer exists, the buffer `*scratch*' is returned.\n\
If BUFFER is omitted or nil, some interesting buffer is returned.\n\
\n\
The ordering is for this screen; If second optional argument SCREEN\n\
is provided, then the ordering is for that screen.  If the second arg\n\
is t, then the global ordering is returned.")
  (buffer, screen)
     register Lisp_Object buffer, screen;
{
  register Lisp_Object tail, buf, notsogood, tem;
  Lisp_Object alist;

  notsogood = Qnil;

#ifdef MULTI_SCREEN
  if (EQ (screen, Qt))
    alist = Vbuffer_alist;
  else if (NILP (screen))
    alist = selected_screen->buffer_alist;
  else
    {
      CHECK_SCREEN (screen, 0);
      alist = XSCREEN (screen)->buffer_alist;
    }
#else
  alist = Vscreen_alist;
#endif

  for (tail = alist; !NILP (tail); tail = Fcdr (tail))
    {
      buf = Fcdr (Fcar (tail));
      if (EQ (buf, buffer))
	continue;
      if (XSTRING (XBUFFER (buf)->name)->data[0] == ' ')
	continue;
      tem = Fget_buffer_window (buf, screen, Qnil);
      if (NILP (tem))
	return buf;
      if (NILP (notsogood))
	notsogood = buf;
    }
  if (!NILP (notsogood))
    return notsogood;
  return Fget_buffer_create (QSscratch);
}

DEFUN ("buffer-disable-undo", Fbuffer_disable_undo, Sbuffer_disable_undo, 1, 1, 0,
  "Make BUFFER stop keeping undo information.\n\
Any undo records it already has are discarded.")
  (buffer)
     register Lisp_Object buffer;
{
  Lisp_Object real_buffer;

  if (NILP (buffer))            /* RMSism */
    real_buffer = Fcurrent_buffer ();
  else
    {
      real_buffer = get_buffer (buffer, 1);
    }
  XBUFFER (real_buffer)->undo_list = Qt;
  return Qnil;
}

DEFUN ("buffer-enable-undo", Fbuffer_enable_undo, Sbuffer_enable_undo,
       0, 1, "",
  "Start keeping undo information for buffer BUFFER.\n\
No argument or nil as argument means do this for the current buffer.")
  (buffer)
     register Lisp_Object buffer;
{
  Lisp_Object real_buffer;

  if (NILP (buffer))            /* RMSism */
    real_buffer = Fcurrent_buffer ();
  else
    real_buffer = get_buffer (buffer, 1);

  if (EQ (XBUFFER (real_buffer)->undo_list, Qt))
    XBUFFER (real_buffer)->undo_list = Qnil;

  return Qnil;
}

DEFUN ("kill-buffer", Fkill_buffer, Skill_buffer, 1, 1, "bKill buffer: ",
  "Kill the buffer BUFFER.\n\
The argument may be a buffer or may be the name of a buffer.\n\
An argument of nil means kill the current buffer.\n\n\
Value is t if the buffer is actually killed, nil if user says no.\n\n\
The value of `kill-buffer-hook' (which may be local to that buffer),\n\
if not void, is a list of functions to be called, with no arguments,\n\
before the buffer is actually killed.  The buffer to be killed is current\n\
when the hook functions are called.\n\
\n\
Any processes that have this buffer as the `process-buffer' are killed\n\
with `delete-process'.")
  (bufname)
     Lisp_Object bufname;
{
  Lisp_Object buf;
  register struct buffer *b;
  struct gcpro gcpro1, gcpro2;

  if (NILP (bufname))
    buf = Fcurrent_buffer ();
  else if (BUFFERP (bufname))
    buf = bufname;
  else
    {
      buf = get_buffer (bufname, 0);
      if (NILP (buf)) nsberror (bufname);
    }

  b = XBUFFER (buf);

  /* Don't kill the minibuffer now current.  */
  if (EQ (buf, Vminibuffer_zero))
    return Qnil;

  /* Query if the buffer is still modified.  */
  if (INTERACTIVE && !NILP (b->filename)
      && BUF_MODIFF (b) > b->save_modified)
    {
      Lisp_Object killp;
      GCPRO2 (buf, bufname);
      killp = call1 (Qyes_or_no_p,
		     (format1 (GETTEXT ("Buffer %s modified; kill anyway? "),
			       XSTRING (b->name)->data)));
      UNGCPRO;
      if (NILP (killp))
	return Qnil;
      b = XBUFFER (buf);        /* Hypothetical relocating GC. */
    }

  /* Run hooks with the buffer to be killed temporarily selected,
     unless the buffer is already dead.
   */
  if (!NILP (b->name))
    {
      int speccount = specpdl_depth ();
      Lisp_Object tail = Qnil;

      GCPRO2 (buf, tail);
      record_unwind_protect (save_excursion_restore, save_excursion_save ());
      Fset_buffer (buf);

      /* First run the query functions; if any query is answered no,
         don't kill the buffer.  */
      for (tail = Vkill_buffer_query_functions;
           !NILP (tail);
           tail = Fcdr (tail))
      {
	if (NILP (call0 (Fcar (tail))))
        {
          UNGCPRO;
	  return unbind_to (speccount, Qnil);
        }
      }

      if (!NILP (Vrun_hooks))
        call1 (Vrun_hooks, Qkill_buffer_hook);
#ifdef HAVE_X_WINDOWS
      /* If an X selection was in this buffer, disown it.
	 We could have done this by simply adding this function to the
	 kill-buffer-hook, but the user might mess that up.
	 */
      if (EQ (Vwindow_system, Qx))
	call0 (intern ("xselect-kill-buffer-hook")); /* >>> generalise me! */
#endif
      unbind_to (speccount, Qnil);
      UNGCPRO;
      b = XBUFFER (buf);        /* Hypothetical relocating GC. */
  }

  /* We have no more questions to ask.  Verify that it is valid
     to kill the buffer.  This must be done after the questions
     since anything can happen within yes-or-no-p.  */

  if (NILP (b->name))
    return Qnil;

  /* Make this buffer not be current.
     In the process, notice if this is the sole visible buffer
     and give up if so.  */
  if (b == current_buffer)
    {
      Fset_buffer (Fother_buffer (buf, Qnil));
      if (b == current_buffer)
	return Qnil;
    }

  /* Now there is no question: we can kill the buffer.  */

#ifdef CLASH_DETECTION
  /* Unlock this buffer's file, if it is locked.  */
  unlock_buffer (b);
#endif /* CLASH_DETECTION */

  {
    int speccount = specpdl_depth ();
    specbind (Qinhibit_quit, Qt);

    kill_buffer_processes (buf);

    /* #### This is a problem if this buffer is in a dedicated window.
       Need to undedicate any windows of this buffer first (and delete them?)
       */
    Freplace_buffer_in_windows (buf);

    delete_from_buffer_alist (buf);

    /* Delete any auto-save file.  */
    if (STRINGP (b->auto_save_file_name))
      {
	if (!NILP (Vdelete_auto_save_files))
	  unlink ((char *) XSTRING (b->auto_save_file_name)->data);
      }

    /* Unchain all markers of this buffer
       and leave them pointing nowhere.  */
    {
      register struct Lisp_Marker *m, *next;
      for (m = b->markers; m; m = next)
	{
	  m->buffer = 0;
	  next = marker_next (m);
	  marker_next (m) = 0;
	}
      b->markers = 0;
    }
    b->name = Qnil;
    BLOCK_INPUT;
    BUFFER_FREE (BUF_BEG_ADDR (b));
    UNBLOCK_INPUT;
    b->undo_list = Qnil;
    free_buffer_cached_stack (b);
    detach_buffer_extents (b);
    unbind_to (speccount, Qnil);
  }
  return Qt;
}

/* Put the element for buffer BUF at the front of buffer-alist.
   This is done when a buffer is selected "visibly".
   It keeps buffer-alist in the order of recency of selection
   so that other_buffer will return something nice.  */

void
record_buffer (buf)
     Lisp_Object buf;
{
  register Lisp_Object link, prev;

  prev = Qnil;
  for (link = Vbuffer_alist; CONSP (link); link = XCONS (link)->cdr)
    {
      if (EQ (XCONS (XCONS (link)->car)->cdr, buf))
	break;
      prev = link;
    }
  /* Effectively do Vbuffer_alist = delq_no_quit (link, Vbuffer_alist) */
  if (NILP (prev))
    Vbuffer_alist = XCONS (Vbuffer_alist)->cdr;
  else
    XCONS (prev)->cdr = XCONS (XCONS (prev)->cdr)->cdr;
  XCONS(link)->cdr = Vbuffer_alist;
  Vbuffer_alist = link;

#ifdef MULTI_SCREEN
  /* That was the global one.  Now do the same thing for the
     per-screen buffer-alist. */
  prev = Qnil;
  for (link = selected_screen->buffer_alist; CONSP (link);
       link = XCONS (link)->cdr)
    {
      if (EQ (XCONS (XCONS (link)->car)->cdr, buf))
	break;
      prev = link;
    }
  /* Effectively do s->buffer_alist = delq_no_quit (link, s->buffer_alist) */
  if (NILP (prev))
    selected_screen->buffer_alist = XCONS (selected_screen->buffer_alist)->cdr;
  else
    XCONS (prev)->cdr = XCONS (XCONS (prev)->cdr)->cdr;
  XCONS(link)->cdr = selected_screen->buffer_alist;
  selected_screen->buffer_alist = link;
#endif

}

DEFUN ("switch-to-buffer", Fswitch_to_buffer, Sswitch_to_buffer, 1, 2, "BSwitch to buffer: ",
  "Select buffer BUFFER in the current window.\n\
BUFFER may be a buffer or a buffer name.\n\
Optional second arg NORECORD non-nil means\n\
do not put this buffer at the front of the list of recently selected ones.\n\
\n\
WARNING: This is NOT the way to work on another buffer temporarily\n\
within a Lisp program!  Use `set-buffer' instead.  That avoids messing with\n\
the window-buffer correspondences.")
  (bufname, norecord)
     Lisp_Object bufname, norecord;
{
  register Lisp_Object buf;
  Lisp_Object tem;

  if (EQ (minibuf_window, selected_window))
    error (GETTEXT ("Cannot switch buffers in minibuffer window"));
  tem = Fwindow_dedicated_p (selected_window);
  if (!NILP (tem))
    error (GETTEXT ("Cannot switch buffers in a dedicated window"));

  if (NILP (bufname))
    buf = Fother_buffer (Fcurrent_buffer (), Qnil);
  else
    buf = Fget_buffer_create (bufname);
  Fset_buffer (buf);
  if (NILP (norecord))
    record_buffer (buf);

  Fset_window_buffer (EQ (selected_window, minibuf_window)
		      ? Fnext_window (minibuf_window, Qnil, Qnil, Qnil)
		      : selected_window,
		      buf);

  return buf;
}

DEFUN ("pop-to-buffer", Fpop_to_buffer, Spop_to_buffer, 1, 3, 0,
  "Select buffer BUFFER in some window, preferably a different one.\n\
If BUFFER is nil, then some other buffer is chosen.\n\
If `pop-up-windows' is non-nil, windows can be split to do this.\n\
If optional second arg OTHER-WINDOW is non-nil, insist on finding another\n\
window even if BUFFER is already visible in the selected window.\n\
If optional third arg is non-nil, it is the screen to pop to this\n\
buffer on.")
  (bufname, not_this_window_p, on_screen)
     Lisp_Object bufname, not_this_window_p, on_screen;
{
  Lisp_Object buf, window, screen;
  if (NILP (bufname))
    buf = Fother_buffer (Fcurrent_buffer (), Qnil);
  else
    buf = Fget_buffer_create (bufname);
  Fset_buffer (buf);
  window = Fdisplay_buffer (buf, not_this_window_p, on_screen);
  screen = Fwindow_screen (window);
  /* if the display-buffer hook decided to show this buffer in another
     screen, then select that screen. */
  if (!EQ (screen, Fselected_screen ()))
    Fselect_screen (screen);
  record_buffer (buf);
  Fselect_window (window);
  return buf;
}

DEFUN ("current-buffer", Fcurrent_buffer, Scurrent_buffer, 0, 0, 0,
  "Return the current buffer as a Lisp object.")
  ()
{
  Lisp_Object buf;
  XSETR (buf, Lisp_Buffer, current_buffer);
  return buf;
}

/* Set the current buffer to b */

void
set_buffer_internal (b)
     register struct buffer *b;
{
  register struct buffer *old_buf;
  register Lisp_Object tail;

  if (current_buffer == b)
    return;

  t_g_cache.valid = 0;
  buffers_changed = 1;
  old_buf = current_buffer;
  current_buffer = b;
  invalidate_current_column ();   /* invalidate indentation cache */

  /* Look down buffer's list of local Lisp variables
     to find and update any that forward into C variables. */

  for (tail = b->local_var_alist; !NILP (tail); tail = XCONS (tail)->cdr)
    {
      Lisp_Object sym = XCONS (XCONS (tail)->car)->car;
      Lisp_Object valcontents = XSYMBOL (sym)->value;
      if (SYMBOL_VALUE_MAGIC_P (valcontents))
	{
	  /* Just reference the variable
	     to cause it to become set for this buffer.  */
	  (void) find_symbol_value (sym);
	}
    }

  /* Do the same with any others that were local to the previous buffer */

  if (old_buf)
    {
      for (tail = old_buf->local_var_alist; 
           !NILP (tail);
           tail = XCONS (tail)->cdr)
	{
	  Lisp_Object sym = XCONS (XCONS (tail)->car)->car;
	  Lisp_Object valcontents = XSYMBOL (sym)->value;

	  if (SYMBOL_VALUE_MAGIC_P (valcontents))
	    {
	      /* Just reference the variable
		 to cause it to become set for this buffer.  */
	      (void) find_symbol_value (sym);
	    }
	}
    }
}

DEFUN ("set-buffer", Fset_buffer, Sset_buffer, 1, 1, 0,
  "Make the buffer BUFFER current for editing operations.\n\
BUFFER may be a buffer or the name of an existing buffer.\n\
See also `save-excursion' when you want to make a buffer current temporarily.\n\
This function does not display the buffer, so its effect ends\n\
when the current command terminates.\n\
Use `switch-to-buffer' or `pop-to-buffer' to switch buffers permanently.")
  (bufname)
     register Lisp_Object bufname;
{
  Lisp_Object buffer;
  buffer = get_buffer (bufname, 0);
  if (NILP (buffer))
    error (GETTEXT ("Selecting deleted buffer"));
  set_buffer_internal (XBUFFER (buffer));
  return buffer;
}

void
barf_if_buffer_read_only (struct buffer *buf, int from, int to)
{
  if (!NILP (Vinhibit_read_only))
    return;
  if (!NILP (buf->read_only))
  {
    Lisp_Object b;
    XSETR (b, Lisp_Buffer, buf);
    Fsignal (Qbuffer_read_only, (list1 (b)));
  }
  if (from > 0)
  {
    if (to < 0) to = from;
    verify_extent_modification (current_buffer, from, to);
  }
}
  

DEFUN ("barf-if-buffer-read-only", Fbarf_if_buffer_read_only,
				   Sbarf_if_buffer_read_only, 0, 3, 0,
  "Signal a `buffer-read-only' error if the buffer is read-only.\n\
Optional argument BUFFER defaults to `(current-buffer)'\n\
If optional arguments START and END are non-nil, all extents in the buffer\n\
which overlap that part of the buffer are checked to ensure none has a\n\
`read-only' property.  END defaults to the value of START.")
  (buffer, start, end)
  Lisp_Object buffer, start, end;
{
  if (NILP (buffer))
    buffer = Fcurrent_buffer ();
  else
    CHECK_BUFFER (buffer, 0);

  if (NILP (start))
    barf_if_buffer_read_only (XBUFFER (buffer), -1, -1);
  else
  {
    CHECK_NATNUM (start, 0);
    if (!NILP (end))
      CHECK_NATNUM (end, 1);
    barf_if_buffer_read_only (XBUFFER (buffer),
                              XINT (start),
                              (!NILP (end) ? XINT (end) : -1));
  }
  return (Qnil);
}

static void
bury_buffer_1 (Lisp_Object buffer, Lisp_Object before,
	       Lisp_Object *buffer_alist)
{
  Lisp_Object aelt = rassq_no_quit (buffer, *buffer_alist);
  Lisp_Object link = memq_no_quit (aelt, *buffer_alist);
  Lisp_Object iter, before_before;

  *buffer_alist = delq_no_quit (aelt, *buffer_alist);
  for (before_before = Qnil, iter = *buffer_alist;
       !NILP (iter) && !EQ (XCONS (XCONS (iter)->car)->cdr, before);
       before_before = iter, iter = XCONS (iter)->cdr)
    ;
  XCONS (link)->cdr = iter;
  if (!NILP (before_before))
    XCONS (before_before)->cdr = link;
  else
    *buffer_alist = link;
}

DEFUN ("bury-buffer", Fbury_buffer, Sbury_buffer, 0, 2, "",
  "Put BUFFER at the end of the list of all buffers.\n\
There it is the least likely candidate for `other-buffer' to return;\n\
thus, the least likely buffer for \\[switch-to-buffer] to select by default.\n\
If BUFFER is nil or omitted, bury the current buffer.\n\
Also, if BUFFER is nil or omitted, remove the current buffer from the\n\
selected window if it is displayed there.\n\
If BEFORE is non-nil, it specifies a buffer before which BUFFER\n\
will be placed, instead of being placed at the end.")
  (buffer, before)
     register Lisp_Object buffer, before;
{
  /* Figure out what buffer we're going to bury.  */
  if (NILP (buffer))
    {
      buffer = Fcurrent_buffer ();

      /* If we're burying the current buffer, unshow it.  */
      Fswitch_to_buffer (Fother_buffer (buffer, Qnil), Qnil);
    }
  else
    {
      buffer = get_buffer (buffer, 1);
    }	  

  if (!NILP (before))
    before = get_buffer (before, 1);

  if (EQ (before, buffer))
    error (GETTEXT ("Cannot place a buffer before itself"));

  bury_buffer_1 (buffer, before, &Vbuffer_alist);
#ifdef MULTI_SCREEN
  bury_buffer_1 (buffer, before, &selected_screen->buffer_alist);
#endif

  return Qnil;
}

DEFUN ("erase-buffer", Ferase_buffer, Serase_buffer, 0, 0, "*",
  "Delete the entire contents of the current buffer.\n\
Any clipping restriction in effect (see `narrow-to-region') is removed,\n\
so the buffer is truly empty after this.")
  ()
{
  t_g_cache.valid = 0;
  Fwiden ();
  del_range (BEG, Z);
  current_buffer->last_window_start = 1;
  /* Prevent warnings, or suspension of auto saving, that would happen
     if future size is less than past size.  Use of erase-buffer
     implies that the future text is not really related to the past text.  */
  current_buffer->save_length = Qzero;
  return Qnil;
}

void
validate_region (b, e)
     register Lisp_Object *b, *e;
{
  CHECK_FIXNUM_COERCE_MARKER (*b, 0);
  CHECK_FIXNUM_COERCE_MARKER (*e, 1);

  if (XINT (*b) > XINT (*e))
    {
      register Lisp_Object i;

      i = *b;
      *b = *e;
      *e = i;
    }

  if (!(BEGV <= XINT (*b) && XINT (*b) <= XINT (*e)
        && XINT (*e) <= ZV))
    args_out_of_range (*b, *e);
}


DEFUN ("kill-all-local-variables", Fkill_all_local_variables, Skill_all_local_variables,
  0, 0, 0,
  "Switch to Fundamental mode by killing current buffer's local variables.\n\
Most local variable bindings are eliminated so that the default values\n\
become effective once more.  Also, the syntax table is set from\n\
`standard-syntax-table', the local keymap is set to nil,\n\
and the abbrev table from `fundamental-mode-abbrev-table'.\n\
This function also forces redisplay of the mode line.\n\
\n\
Every function to select a new major mode starts by\n\
calling this function.\n\n\
As a special exception, local variables whose names have\n\
a non-nil `permanent-local' property are not eliminated by this function.\n\
\n\
The first thing this function does is run\n\
the normal hook `change-major-mode-hook'.")
  ()
{
  if (!NILP (Vrun_hooks))
  {
    call1 (Vrun_hooks, Qchange_major_mode_hook);
  }

  reset_buffer_local_variables (current_buffer);

  kill_buffer_local_variables (current_buffer);

  /* Force mode-line redisplay.  Useful here because all major mode
     commands call this function.  */
  redraw_mode_line++;

  return Qnil;
}

static void
nuke_all_buffer_slots (struct buffer *b, Lisp_Object zap)
{
  struct lcrecord_header save;

  save = b->header;
  memset (b, 0, sizeof (*b));
  b->header = save;

#define MARKED_SLOT(x)	b->x = (zap);
#include "bufslots.h"
#undef MARKED_SLOT
}

void
init_buffer_once ()
{
  /* Make sure all markable slots in buffer_defaults
     are initialized reasonably, so mark_buffer won't choke.
   */
  struct buffer *defs = alloc_lcrecord (sizeof(struct buffer), lrecord_buffer);
  struct buffer *syms = alloc_lcrecord (sizeof(struct buffer), lrecord_buffer);
  XSETR (Vbuffer_defaults, Lisp_Buffer, defs);
  XSETR (Vbuffer_local_symbols, Lisp_Buffer, syms);

  nuke_all_buffer_slots (syms, Qnil);
  nuke_all_buffer_slots (defs, Qnil);

  QSFundamental = Fpurecopy (build_string ("Fundamental"));
  QSscratch = Fpurecopy (build_string ("*scratch*"));
  defsymbol (&Qfundamental_mode, "fundamental-mode");

  /* Set up the non-nil default values of various buffer slots.
     Must do these before making the first buffer.
   */
  defs->major_mode = Qfundamental_mode;
  defs->mode_name = QSFundamental;
  defs->abbrev_table = Qnil;    /* real default setup by Lisp code */
  defs->downcase_table = Vascii_downcase_table;
  defs->upcase_table = Vascii_upcase_table;
  defs->case_canon_table = Vascii_canon_table;
  defs->case_eqv_table = Vascii_eqv_table;
  defs->syntax_table = Vstandard_syntax_table;
  defs->mode_line_format = build_string ("%-");  /* reset in loaddefs.el */
  defs->case_fold_search = Qt;
  defs->selective_display_ellipses = Qt;
  defs->tab_width = make_number (8);
  defs->ctl_arrow = Qt;
  defs->fill_column = make_number (70);
  defs->left_margin = Qzero;
  defs->save_length = Qzero;       /* lisp code wants int-or-nil */
  defs->modtime = 0;
  defs->save_modified = 1;
  defs->auto_save_modified = 0;
  defs->auto_save_failure_time = -1;

  {
    /*  0 means var is always local.  Default used only at creation.
     * -1 means var is always local.  Default used only at reset and creation.
     * -2 means there's no lisp variable corresponding to this slot
     *    and the default is only used at creation.
     * -3 means no Lisp variable.  Default used only at reset and creation.
     * >0 is mask.  Var is local if ((buffer->local_var_flags & mask) != 0)
     *              Otherwise default is used.
     */
    Lisp_Object always_local_no_default = make_number (0);
    Lisp_Object always_local_resettable = make_number (-1);
    Lisp_Object resettable = make_number (-3);

    /* Assign the local-flags to the slots that have default values.
       The local flag is a bit that is used in the buffer
       to say that it has its own local value for the slot.
       The local flag bits are in the local_var_flags slot of the buffer.  */

    nuke_all_buffer_slots (&buffer_local_flags, make_number (-2));
    buffer_local_flags.filename = always_local_no_default;
    buffer_local_flags.truename = always_local_no_default;
    buffer_local_flags.directory = always_local_no_default;
    buffer_local_flags.backed_up = always_local_no_default;
    buffer_local_flags.save_length = always_local_no_default;
    buffer_local_flags.auto_save_file_name = always_local_no_default;
    buffer_local_flags.read_only = always_local_no_default;

    buffer_local_flags.major_mode = always_local_resettable;
    buffer_local_flags.mode_name = always_local_resettable;
    buffer_local_flags.undo_list = always_local_no_default;
#if 0 /* RMSmacs */
    buffer_local_flags.mark_active = always_local_resettable;
#endif
    buffer_local_flags.keymap = resettable;
    buffer_local_flags.downcase_table = resettable;
    buffer_local_flags.upcase_table = resettable;
    buffer_local_flags.case_canon_table = resettable;
    buffer_local_flags.case_eqv_table = resettable;
    buffer_local_flags.syntax_table = resettable;

    buffer_local_flags.mode_line_format = make_number (1);
    buffer_local_flags.abbrev_mode = make_number (2);
    buffer_local_flags.overwrite_mode = make_number (4);
    buffer_local_flags.case_fold_search = make_number (8);
    buffer_local_flags.auto_fill_function = make_number (0x10);
    buffer_local_flags.selective_display = make_number (0x20);
    buffer_local_flags.selective_display_ellipses = make_number (0x40);
    buffer_local_flags.tab_width = make_number (0x80);
    buffer_local_flags.truncate_lines = make_number (0x100);
    buffer_local_flags.ctl_arrow = make_number (0x200);
    buffer_local_flags.fill_column = make_number (0x400);
    buffer_local_flags.left_margin = make_number (0x800);
    buffer_local_flags.abbrev_table = make_number (0x1000);
    buffer_local_flags.display_table = make_number (0x2000);
    buffer_local_flags.use_left_overflow = make_number (0x4000);
#ifdef MSDOS
    buffer_local_flags.buffer_file_type = make_number (0x8000);
#endif
  }

  /* Check for DEFVAR_BUFFER_LOCAL without initializing the corresponding
     slot of buffer_local_flags and vice-versa. */
#define MARKED_SLOT(slot) \
  if (!!(XINT (buffer_local_flags.slot) <= -1) \
      != !!(NILP (XBUFFER (Vbuffer_local_symbols)->slot))) \
    abort ();
#undef MARKED_SLOT

  Vbuffer_alist = Qnil;
  current_buffer = 0;

#ifdef MULTI_SCREEN
  Vscreen_list = Qnil;
#endif

  Vprin1_to_string_buffer
    = Fget_buffer_create (Fpurecopy (build_string (" prin1")));
  /* Reset Vbuffer_alist again so that the above buf is magically invisible */
  Vbuffer_alist = Qnil;
  /* Want no undo records for prin1_to_string_buffer */
  Fbuffer_disable_undo (Vprin1_to_string_buffer);

  {
    Lisp_Object scratch = Fset_buffer (Fget_buffer_create (QSscratch));
    /* Want no undo records for *scratch* until after Emacs is dumped */
    Fbuffer_disable_undo (scratch);
  }
}

void
init_buffer ()
{
  char buf[MAXPATHLEN+1];

  buf[0] = 0;

  Fset_buffer (Fget_buffer_create (QSscratch));

#ifndef VMS /* Need filename-syntax-indepentent absolute-pathname-p ! */
  {
    /* If PWD is accurate, use it instead of calling getwd.  This is faster
       when PWD is right, and may avoid a fatal error.  */
    struct stat dotstat, pwdstat;
    char *pwd = getenv ("PWD");

    if (pwd && pwd[0] == '/'
        && stat (pwd, &pwdstat) == 0
        && stat (".", &dotstat) == 0
        && dotstat.st_ino == pwdstat.st_ino
        && dotstat.st_dev == pwdstat.st_dev
        && strlen (pwd) < MAXPATHLEN)
      strcpy (buf, pwd);
  }
#endif /* not VMS */
  if (buf[0] == 0)
    {
      /* PWD env var didn't work for us */
      if (getwd (buf) == 0)
	fatal (GETTEXT ("`getwd' failed: %s."), buf);
    }

#ifndef VMS
  /* Maybe this should really use some standard subroutine
     whose definition is filename syntax dependent.  */
  if (buf[strlen (buf) - 1] != '/')
    strcat (buf, "/");
#endif /* not VMS */
  current_buffer->directory = build_string (buf);
}

/* DOC is ignored because it is snagged and recorded externally 
 *  by make-docfile */
/* Renamed from DEFVAR_PER_BUFFER because FSFmacs D_P_B takes
 *  a bogus extra arg, which confuses an otherwise identical make-docfile.c */
#define DEFVAR_BUFFER_LOCAL(lname, field_name, doc)  \
 do { static CONST struct symbol_value_forward I_hate_C \
       = { { { { lrecord_symbol_value_forward }, \
               (void *) &(buffer_local_flags.field_name), 69 }, \
             current_buffer_forward } }; \
      defvar_buffer_local ((lname), &I_hate_C); \
 } while (0)

static void
defvar_buffer_local (CONST char *namestring, 
                     CONST struct symbol_value_forward *m)
{
  int offset = ((char *)symbol_value_forward_forward (m)
                - (char *)&buffer_local_flags);

  defvar_mumble (namestring, m, sizeof (*m));

  *((Lisp_Object *)(offset + (char *)XBUFFER (Vbuffer_local_symbols))) 
    = intern (namestring);
}

/* DOC is ignored because it is snagged and recorded externally 
 *  by make-docfile */
#define DEFVAR_BUFFER_DEFAULTS(lname, field_name, doc)  \
 do { static CONST struct symbol_value_forward I_hate_C \
       = { { { { lrecord_symbol_value_forward }, \
               (void *) &(buffer_local_flags.field_name), 69 }, \
             default_buffer_forward } }; \
      defvar_mumble ((lname), &I_hate_C, sizeof (I_hate_C)); \
 } while (0)

/* initialize the buffer routines */
void
syms_of_buffer ()
{
  staticpro (&Vbuffer_defaults);
  staticpro (&Vbuffer_local_symbols);
  staticpro (&Qfundamental_mode);
  staticpro (&QSFundamental);
  staticpro (&QSscratch);
  staticpro (&Vbuffer_alist);

  defsymbol (&Qmode_class, "mode-class");
  defsymbol (&Qrename_auto_save_file, "rename-auto-save-file");
  defsymbol (&Qkill_buffer_hook, "kill-buffer-hook");
  defsymbol (&Qpermanent_local, "permanent-local");
  defsymbol (&Qprotected_field, "protected-field");

  defsymbol (&Qfirst_change_hook, "first-change-hook");
  defsymbol (&Qbefore_change_functions, "before-change-functions");
  defsymbol (&Qafter_change_functions, "after-change-functions");

  /* #### Obsolete, for compatibility */
  defsymbol (&Qbefore_change_function, "before-change-function");
  defsymbol (&Qafter_change_function, "after-change-function");

  defsymbol (&Qbuffer_file_name, "buffer-file-name");
  defsymbol (&Qbuffer_undo_list, "buffer-undo-list");
  defsymbol (&Qdefault_directory, "default-directory");

  defsymbol (&Qget_file_buffer, "get-file-buffer");
  defsymbol (&Qchange_major_mode_hook, "change-major-mode-hook");

  pure_put (Qprotected_field, Qerror_conditions,
	    list2 (Qprotected_field, Qerror));
  pure_put (Qprotected_field, Qerror_message,
	    build_string (DEFER_GETTEXT ("Attempt to modify a protected field")));

  DEFVAR_BUFFER_DEFAULTS ("default-mode-line-format", mode_line_format,
    "Default value of `mode-line-format' for buffers that don't override it.\n\
This is the same as (default-value 'mode-line-format).");

  DEFVAR_BUFFER_DEFAULTS ("default-abbrev-mode", abbrev_mode,
    "Default value of `abbrev-mode' for buffers that do not override it.\n\
This is the same as (default-value 'abbrev-mode).");

  DEFVAR_BUFFER_DEFAULTS ("default-ctl-arrow", ctl_arrow,
    "Default value of `ctl-arrow' for buffers that do not override it.\n\
This is the same as (default-value 'ctl-arrow).");

  DEFVAR_BUFFER_DEFAULTS ("default-truncate-lines", truncate_lines,
    "Default value of `truncate-lines' for buffers that do not override it.\n\
This is the same as (default-value 'truncate-lines).");

  DEFVAR_BUFFER_DEFAULTS ("default-fill-column", fill_column,
    "Default value of `fill-column' for buffers that do not override it.\n\
This is the same as (default-value 'fill-column).");

  DEFVAR_BUFFER_DEFAULTS ("default-left-margin", left_margin,
    "Default value of `left-margin' for buffers that do not override it.\n\
This is the same as (default-value 'left-margin).");

  DEFVAR_BUFFER_DEFAULTS ("default-tab-width", tab_width,
    "Default value of `tab-width' for buffers that do not override it.\n\
This is the same as (default-value 'tab-width).");

  DEFVAR_BUFFER_DEFAULTS ("default-use-left-overflow", use_left_overflow,
   "Default value of `use-left-overflow' for buffers that do not override it.\n\
This is the same as (default-value 'use-left-overflow).");

  DEFVAR_BUFFER_DEFAULTS ("default-case-fold-search", case_fold_search,
    "Default value of `case-fold-search' for buffers that don't override it.\n\
This is the same as (default-value 'case-fold-search).");

#ifdef MSDOS
  DEFVAR_BUFFER_DEFAULTS ("default-buffer-file-type", buffer_file_type,
    "Default file type for buffers that do not override it.\n\
This is the same as (default-value 'buffer-file-type).\n\
The file type is nil for text, t for binary.");
#endif

  DEFVAR_BUFFER_LOCAL ("mode-line-format", mode_line_format, 0);

/* This doc string is too long for cpp; cpp dies if it isn't in a comment.
   But make-docfile finds it!
  DEFVAR_BUFFER_LOCAL ("mode-line-format", mode_line_format,
    "Template for displaying mode line for current buffer.\n\
Each buffer has its own value of this variable.\n\
Value may be a string, a symbol or a list or cons cell.\n\
For a symbol, its value is used (but it is ignored if t or nil).\n\
 A string appearing directly as the value of a symbol is processed verbatim\n\
 in that the %-constructs below are not recognized.\n\
For a list whose car is a symbol, the symbol's value is taken,\n\
 and if that is non-nil, the cadr of the list is processed recursively.\n\
 Otherwise, the caddr of the list (if there is one) is processed.\n\
For a list whose car is a string or list, each element is processed\n\
 recursively and the results are effectively concatenated.\n\
For a list whose car is an integer, the cdr of the list is processed\n\
  and padded (if the number is positive) or truncated (if negative)\n\
  to the width specified by that number.\n\
A string is printed verbatim in the mode line except for %-constructs:\n\
  (%-constructs are allowed when the string is the entire mode-line-format\n\
   or when it is found in a cons-cell or a list)\n\
  %b -- print buffer name.      %f -- print visited file name.\n\
  %* -- print %, * or hyphen, if buffer is read-only, modified or neither.\n\
  %+ -- print * or hyphen       %m -- print value of mode-name (obsolete).\n\
  %s -- print process status.   %l -- print the current line number.\n\
  %S -- print name of selected screen (only meaningful under X Windows).\n\
  %p -- print percent of buffer above top of window, or Top, Bot or All.\n\
  %P -- print percent of buffer above bottom of window, perhaps plus Top,\n\
        or print Bottom or All.\n\
  %n -- print Narrow if appropriate.\n\
  %[ -- print one [ for each recursive editing level.  %] similar.\n\
  %% -- print %.                %- -- print infinitely many dashes.\n\
Decimal digits after the % specify field width to which to pad.");
*/

  DEFVAR_BUFFER_DEFAULTS ("default-major-mode", major_mode,
    "*Major mode for new buffers.  Defaults to `fundamental-mode'.\n\
nil here means use current buffer's major mode.");

  DEFVAR_BUFFER_DEFAULTS ("fundamental-mode-abbrev-table", abbrev_table,
    "The abbrev table of mode-specific abbrevs for Fundamental Mode.");

  DEFVAR_BUFFER_LOCAL ("major-mode", major_mode,
    "Symbol for current buffer's major mode.");

  DEFVAR_BUFFER_LOCAL ("mode-name", mode_name,
    "Pretty name of current buffer's major mode (a string).");

  DEFVAR_BUFFER_LOCAL ("abbrev-mode", abbrev_mode,
    "Non-nil turns on automatic expansion of abbrevs as they are inserted.\n\
Automatically becomes buffer-local when set in any fashion.");

  DEFVAR_BUFFER_LOCAL ("case-fold-search", case_fold_search,
    "*Non-nil if searches should ignore case.\n\
Automatically becomes buffer-local when set in any fashion.");

  DEFVAR_BUFFER_LOCAL ("fill-column", fill_column,
    "*Column beyond which automatic line-wrapping should happen.\n\
Automatically becomes buffer-local when set in any fashion.");

  DEFVAR_BUFFER_LOCAL ("left-margin", left_margin,
    "*Column for the default indent-line-function to indent to.\n\
Linefeed indents to this column in Fundamental mode.\n\
Automatically becomes buffer-local when set in any fashion.");

  DEFVAR_BUFFER_LOCAL ("use-left-overflow", use_left_overflow,
    "*Non-nil means use the left outside margin as extra whitespace when\n\
displaying 'whitespace or 'inside-margin glyphs.\n\
Automatically becomes buffer-local when set in any fashion.");

  DEFVAR_BUFFER_LOCAL ("tab-width", tab_width,
    "*Distance between tab stops (for display of tab characters), in columns.\n\
Automatically becomes buffer-local when set in any fashion.");

  DEFVAR_BUFFER_LOCAL ("ctl-arrow", ctl_arrow,
    "*Non-nil means display control chars with uparrow.\n\
Nil means use backslash and octal digits.\n\
An integer means characters >= ctl-arrow are assumed to be printable, and\n\
will be displayed as a single glyph.\n\
Any other value is the same as 160 - the code SPC with the high bit on.\n\
\n\
The interpretation of this variable is likely to change in the future.\n\
\n\
Automatically becomes buffer-local when set in any fashion.\n\
This variable does not apply to characters whose display is specified\n\
in the current display table (if there is one).");

  DEFVAR_BUFFER_LOCAL ("truncate-lines", truncate_lines,
    "*Non-nil means do not display continuation lines;\n\
give each line of text one screen line.\n\
Automatically becomes buffer-local when set in any fashion.\n\
\n\
Note that this is overridden by the variable\n\
`truncate-partial-width-windows' if that variable is non-nil\n\
and this buffer is not full-screen width.");

  DEFVAR_BUFFER_LOCAL ("default-directory", directory,
    "Name of default directory of current buffer.  Should end with slash.\n\
Each buffer has its own value of this variable.");

#ifdef MSDOS
  DEFVAR_BUFFER_LOCAL ("buffer-file-type", buffer_file_type,
    "*If visited file is text, nil; otherwise, t.");
#endif

  DEFVAR_BUFFER_LOCAL ("auto-fill-function", auto_fill_function,
    "Function called (if non-nil) to perform auto-fill.\n\
It is called after self-inserting a space at a column beyond `fill-column'.\n\
Each buffer has its own value of this variable.\n\
NOTE: This variable is not an ordinary hook;\n\
It may not be a list of functions.");

  DEFVAR_BUFFER_LOCAL ("buffer-file-name", filename,
    "Name of file visited in current buffer, or nil if not visiting a file.\n\
Each buffer has its own value of this variable.");

  DEFVAR_BUFFER_LOCAL ("buffer-file-truename", truename,
    "The real name of the file visited in the current buffer, \n\
or nil if not visiting a file.  This is the result of passing \n\
buffer-file-name to the `truename' function.  Every buffer has \n\
its own value of this variable.  This variable is automatically \n\
maintained by the functions that change the file name associated \n\
with a buffer.");

  DEFVAR_BUFFER_LOCAL ("buffer-auto-save-file-name", auto_save_file_name,
    "Name of file for auto-saving current buffer,\n\
or nil if buffer should not be auto-saved.\n\
Each buffer has its own value of this variable.");

  DEFVAR_BUFFER_LOCAL ("buffer-read-only", read_only,
    "Non-nil if this buffer is read-only.\n\
Each buffer has its own value of this variable.");

  DEFVAR_BUFFER_LOCAL ("buffer-backed-up", backed_up,
    "Non-nil if this buffer's file has been backed up.\n\
Backing up is done before the first time the file is saved.\n\
Each buffer has its own value of this variable.");

  DEFVAR_BUFFER_LOCAL ("buffer-saved-size", save_length,
    "Length of current buffer when last read in, saved or auto-saved.\n\
0 initially.\n\
Each buffer has its own value of this variable.");

  DEFVAR_BUFFER_LOCAL ("selective-display", selective_display,
    "Non-nil enables selective display:\n\
Integer N as value means display only lines\n\
 that start with less than n columns of space.\n\
A value of t means, after a ^M, all the rest of the line is invisible.\n\
 Then ^M's in the file are written into files as newlines.\n\n\
Automatically becomes buffer-local when set in any fashion.");

  DEFVAR_BUFFER_LOCAL ("selective-display-ellipses", selective_display_ellipses,
    "t means display ... on previous line when a line is invisible.\n\
Automatically becomes buffer-local when set in any fashion.");

  DEFVAR_BUFFER_LOCAL ("local-abbrev-table", abbrev_table,
    "Local (mode-specific) abbrev table of current buffer.");

  DEFVAR_BUFFER_LOCAL ("overwrite-mode", overwrite_mode,
    "Non-nil if self-insertion should replace existing text.\n\
If non-nil and not `overwrite-mode-binary', self-insertion still\n\
inserts at the end of a line, and inserts when point is before a tab,\n\
until the tab is filled in.\n\
If `overwrite-mode-binary', self-insertion replaces newlines and tabs too.\n\
Automatically becomes buffer-local when set in any fashion.");

#if 0
  xxxDEFVAR_BUFFER_LOCAL ("buffer-display-table", display_table,
    "Display table that controls display of the contents of current buffer.\n\
Automatically becomes buffer-local when set in any fashion.\n\
The display table is a vector created with `make-display-table'.\n\
The first 256 elements control how to display each possible text character.\n\
Each value should be a vector of characters or nil;\n\
nil means display the character in the default fashion.\n\
The remaining five elements control the display of\n\
  the end of a truncated screen line (element 256, a single character);\n\
  the end of a continued line (element 257, a single character);\n\
  the escape character used to display character codes in octal\n\
    (element 258, a single character);\n\
  the character used as an arrow for control characters (element 259,\n\
    a single character);\n\
  the decoration indicating the presence of invisible lines (element 260,\n\
    a vector of characters).\n\
If this variable is nil, the value of `standard-display-table' is used.\n\
Each window can have its own, overriding display table.");
#endif

  DEFVAR_BOOL ("find-file-compare-truenames", &find_file_compare_truenames,
    "If this is true, then the find-file command will check the truenames\n\
of all visited files when deciding whether a given file is already in\n\
a buffer, instead of just the buffer-file-name.  This means that if you\n\
attempt to visit another file which is a symbolic-link to a file which is\n\
already in a buffer, the existing buffer will be found instead of a newly-\n\
created one.  This works if any component of the pathname (including a non-\n\
terminal component) is a symbolic link as well, but doesn't work with hard\n\
links (nothing does.)\n\
\n\
See also the variable find-file-use-truenames.");
  find_file_compare_truenames = 0;

  DEFVAR_BOOL ("find-file-use-truenames", &find_file_use_truenames,
    "If this is true, then a buffer's visited file-name will always be\n\
chased back to the real file; it will never be a symbolic link, and there\n\
will never be a symbolic link anywhere in its directory path.\n\
That is, the buffer-file-name and buffer-file-truename will be equal.\n\
This doesn't work with hard links.\n\
\n\
See also the variable find-file-compare-truenames.");
  find_file_use_truenames = 0;

  DEFVAR_LISP ("before-change-functions", &Vbefore_change_functions,
	       "List of functions to call before each text change.\n\
Two arguments are passed to each function: the positions of\n\
the beginning and end of the range of old text to be changed.\n\
\(For an insertion, the beginning and end are at the same place.)\n\
No information is given about the length of the text after the change.\n\
position of the change\n\
\n\
Buffer changes made while executing `before-change-functions'\n\
don't call any before-change or after-change functions.");
  Vbefore_change_functions = Qnil;

  DEFVAR_LISP ("after-change-functions", &Vafter_change_functions,
	       "List of functions to call after each text change.\n\
Three arguments are passed to each function: the positions of\n\
the beginning and end of the range of changed text,\n\
and the length of the pre-change text replaced by that range.\n\
\(For an insertion, the pre-change length is zero;\n\
for a deletion, that length is the number of characters deleted,\n\
and the post-change beginning and end are at the same place.)\n\
\n\
Buffer changes made while executing `after-change-functions'\n\
don't call any before-change or after-change functions.");
  Vafter_change_functions = Qnil;

  DEFVAR_LISP ("before-change-function", &Vbefore_change_function,	/* #### */
	       "Obsolete.  Use `before-change-functions' instead.");
  Vbefore_change_function = Qnil;

  DEFVAR_LISP ("after-change-function", &Vafter_change_function,	/* #### */
	       "Obsolete.  Use `after-change-functions' instead.");
  Vafter_change_function = Qnil;

  DEFVAR_LISP ("first-change-hook", &Vfirst_change_hook,
  "A list of functions to call before changing a buffer which is unmodified.\n\
The functions are run using the `run-hooks' function.");
  Vfirst_change_hook = Qnil;

  DEFVAR_BUFFER_LOCAL ("buffer-undo-list", undo_list,
    "List of undo entries in current buffer.\n\
Recent changes come first; older changes follow newer.\n\
\n\
An entry (START . END) represents an insertion which begins at\n\
position START and ends at position END.\n\
\n\
An entry (TEXT . POSITION) represents the deletion of the string TEXT\n\
from (abs POSITION).  If POSITION is positive, point was at the front\n\
of the text being deleted; if negative, point was at the end.\n\
\n\
An entry (t HIGHWORD LOWWORD) indicates that the buffer had been\n\
previously unmodified.  HIGHWORD and LOWWORD are the high and low\n\
16-bit words of the buffer's modification count at the time.  If the\n\
modification count of the most recent save is different, this entry is\n\
obsolete.\n\
\n\
An entry of the form POSITION indicates that point was at the buffer\n\
location given by the integer.  Undoing an entry of this form places\n\
point at POSITION.\n\
\n\
An entry of the form POSITION indicates that point was at the buffer\n\
location given by the integer.  Undoing an entry of this form places\n\
point at POSITION.\n\
\n\
nil marks undo boundaries.  The undo command treats the changes\n\
between two undo boundaries as a single step to be undone.\n\
\n\
If the value of the variable is t, undo information is not recorded.");

#if 0 /* RMSmacs */
  DEFVAR_BUFFER_LOCAL ("mark-active", mark_active, 
    "Non-nil means the mark and region are currently active in this buffer.\n\
Automatically local in all buffers.");

  DEFVAR_LISP ("transient-mark-mode", &Vtransient_mark_mode,
    "*Non-nil means deactivate the mark when the buffer contents change.");
  Vtransient_mark_mode = Qnil;
#endif

  DEFVAR_INT ("undo-threshold", &undo_threshold,
    "Keep no more undo information once it exceeds this size.\n\
This threshold is applied when garbage collection happens.\n\
The size is counted as the number of bytes occupied,\n\
which includes both saved text and other data.");
  undo_threshold = 20000;

  DEFVAR_INT ("undo-high-threshold", &undo_high_threshold,
    "Don't keep more than this much size of undo information.\n\
A command which pushes past this size is itself forgotten.\n\
This threshold is applied when garbage collection happens.\n\
The size is counted as the number of bytes occupied,\n\
which includes both saved text and other data.");
  undo_high_threshold = 30000;

  DEFVAR_LISP ("inhibit-read-only", &Vinhibit_read_only,
    "*Non-nil means disregard read-only status of buffers or characters.\n\
If the value is t, disregard `buffer-read-only' and all `read-only'\n\
text properties.  If the value is a list, disregard `buffer-read-only'\n\
and disregard a `read-only' text property if the property value\n\
is a member of the list.");
  Vinhibit_read_only = Qnil;

  DEFVAR_LISP ("kill-buffer-query-functions", &Vkill_buffer_query_functions,
    "List of functions called with no args to query before killing a buffer.");
  Vkill_buffer_query_functions = Qnil;

  DEFVAR_LISP ("delete-auto-save-files", &Vdelete_auto_save_files,
    "*Non-nil means delete a buffer's auto-save file when the buffer is saved\n\
or killed.");
  Vdelete_auto_save_files = Qt;
  

  defsubr (&Sbufferp);
  defsubr (&Sbuffer_list);
  defsubr (&Sget_buffer);
  defsubr (&Sget_file_buffer);
  defsubr (&Sget_buffer_create);

  defsubr (&Sset_buffer_left_margin_width);
  defsubr (&Sbuffer_left_margin_width);
  defsubr (&Sset_buffer_right_margin_width);
  defsubr (&Sbuffer_right_margin_width);

  defsubr (&Sgenerate_new_buffer_name);
  defsubr (&Sbuffer_name);
  defsubr (&Sbuffer_file_name);
  defsubr (&Sbuffer_local_variables);
  defsubr (&Sbuffer_dedicated_screen);
  defsubr (&Sset_buffer_dedicated_screen);
  defsubr (&Sbuffer_modified_p);
  defsubr (&Sset_buffer_modified_p);
  defsubr (&Sbuffer_modified_tick);
  defsubr (&Srename_buffer);
  defsubr (&Sother_buffer);
  defsubr (&Sbuffer_disable_undo);
  defsubr (&Sbuffer_enable_undo);
  defsubr (&Skill_buffer);
  defsubr (&Serase_buffer);
  defsubr (&Sswitch_to_buffer);
  defsubr (&Spop_to_buffer);
  defsubr (&Scurrent_buffer);
  defsubr (&Sset_buffer);
  defsubr (&Sbarf_if_buffer_read_only);
  defsubr (&Sbury_buffer);
  defsubr (&Skill_all_local_variables);

#if 0 /* RMSmacs */
  defsubr (&Soverlayp);
  defsubr (&Smake_overlay);
  defsubr (&Sdelete_overlay);
  defsubr (&Smove_overlay);
  defsubr (&Soverlay_start);
  defsubr (&Soverlay_end);
  defsubr (&Soverlay_buffer);
  defsubr (&Soverlay_properties);
  defsubr (&Soverlays_at);
  defsubr (&Snext_overlay_change);
  defsubr (&Soverlay_recenter);
  defsubr (&Soverlay_lists);
  defsubr (&Soverlay_get);
  defsubr (&Soverlay_put);
#endif
}
