(U+64B9): Add J78-5978 and J{83|90}-3349.

[chise/xemacs-chise.git-] / info / xemacs.info-8

This is ../info/xemacs.info, produced by makeinfo version 4.0 from
xemacs/xemacs.texi.

INFO-DIR-SECTION XEmacs Editor
START-INFO-DIR-ENTRY
* XEmacs: (xemacs).             XEmacs Editor.
END-INFO-DIR-ENTRY

   This file documents the XEmacs editor.

   Copyright (C) 1985, 1986, 1988 Richard M. Stallman.  Copyright (C)
1991, 1992, 1993, 1994 Lucid, Inc.  Copyright (C) 1993, 1994 Sun
Microsystems, Inc.  Copyright (C) 1995 Amdahl Corporation.

   Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.

   Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided also
that the sections entitled "The GNU Manifesto", "Distribution" and "GNU
General Public License" are included exactly as in the original, and
provided that the entire resulting derived work is distributed under the
terms of a permission notice identical to this one.

   Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that the sections entitled "The GNU Manifesto",
"Distribution" and "GNU General Public License" may be included in a
translation approved by the author instead of in the original English.

\1f
File: xemacs.info,  Node: Making Snapshots,  Next: Snapshot Caveats,  Prev: Snapshots,  Up: Snapshots

Making and Using Snapshots
..........................

   There are two basic commands for snapshots; one makes a snapshot
with a given name, the other retrieves a named snapshot.

`C-x v s NAME <RET>'
     Define the last saved versions of every registered file in or
     under the current directory as a snapshot named NAME
     (`vc-create-snapshot').

`C-x v r NAME <RET>'
     Check out all registered files at or below the current directory
     level using whatever versions correspond to the snapshot NAME
     (`vc-retrieve-snapshot').

     This command reports an error if any files are locked at or below
     the current directory, without changing anything; this is to avoid
     overwriting work in progress.

   A snapshot uses a very small amount of resources--just enough to
record the list of file names and which version belongs to the
snapshot.  Thus, you need not hesitate to create snapshots whenever
they are useful.

   You can give a snapshot name as an argument to `C-x v =' or `C-x v
~' (*note Old Versions::).  Thus, you can use it to compare a snapshot
against the current files, or two snapshots against each other, or a
snapshot against a named version.

\1f
File: xemacs.info,  Node: Snapshot Caveats,  Prev: Making Snapshots,  Up: Snapshots

Snapshot Caveats
................

   VC's snapshot facilities are modeled on RCS's named-configuration
support.  They use RCS's native facilities for this, so under VC
snapshots made using RCS are visible even when you bypass VC.

   For SCCS, VC implements snapshots itself.  The files it uses contain
name/file/version-number triples.  These snapshots are visible only
through VC.

   A snapshot is a set of checked-in versions.  So make sure that all
the files are checked in and not locked when you make a snapshot.

   File renaming and deletion can create some difficulties with
snapshots.  This is not a VC-specific problem, but a general design
issue in version control systems that no one has solved very well yet.

   If you rename a registered file, you need to rename its master along
with it (the command `vc-rename-file' does this automatically).  If you
are using SCCS, you must also update the records of the snapshot, to
mention the file by its new name (`vc-rename-file' does this, too).  An
old snapshot that refers to a master file that no longer exists under
the recorded name is invalid; VC can no longer retrieve it.  It would
be beyond the scope of this manual to explain enough about RCS and SCCS
to explain how to update the snapshots by hand.

   Using `vc-rename-file' makes the snapshot remain valid for
retrieval, but it does not solve all problems.  For example, some of the
files in the program probably refer to others by name.  At the very
least, the makefile probably mentions the file that you renamed.  If you
retrieve an old snapshot, the renamed file is retrieved under its new
name, which is not the name that the makefile expects.  So the program
won't really work as retrieved.

\1f
File: xemacs.info,  Node: Version Headers,  Prev: Snapshots,  Up: Version Control

Inserting Version Control Headers
---------------------------------

   Sometimes it is convenient to put version identification strings
directly into working files.  Certain special strings called "version
headers" are replaced in each successive version by the number of that
version.

   You can use the `C-x v h' command (`vc-insert-headers') to insert a
suitable header string.

`C-x v h'
     Insert headers in a file for use with your version-control system.

   The default header string is `\$Id\$' for RCS and `\%W\%' for SCCS.
(The actual strings inserted do not have the backslashes in them.  They
were placed in the Info source file so that the strings don't get
interpreted as version-control headers when the Info source files are
maintained under version control.) You can specify other headers to
insert by setting the variable `vc-header-alist'.  Its value is a list
of elements of the form `(PROGRAM . STRING)' where PROGRAM is `RCS' or
`SCCS' and STRING is the string to use.

   Instead of a single string, you can specify a list of strings; then
each string in the list is inserted as a separate header on a line of
its own.

   It is often necessary to use "superfluous" backslashes when writing
the strings that you put in this variable.  This is to prevent the
string in the constant from being interpreted as a header itself if the
Emacs Lisp file containing it is maintained with version control.

   Each header is inserted surrounded by tabs, inside comment
delimiters, on a new line at the start of the buffer.  Normally the
ordinary comment start and comment end strings of the current mode are
used, but for certain modes, there are special comment delimiters for
this purpose; the variable `vc-comment-alist' specifies them.  Each
element of this list has the form `(MODE STARTER ENDER)'.

   The variable `vc-static-header-alist' specifies further strings to
add based on the name of the buffer.  Its value should be a list of
elements of the form `(REGEXP . FORMAT)'.  Whenever REGEXP matches the
buffer name, FORMAT is inserted as part of the header.  A header line
is inserted for each element that matches the buffer name, and for each
string specified by `vc-header-alist'.  The header line is made by
processing the string from `vc-header-alist' with the format taken from
the element.  The default value for `vc-static-header-alist' is:

     (("\\.c$" .
       "\n#ifndef lint\nstatic char vcid[] = \"\%s\";\n\
     #endif /* lint */\n"))

which specifies insertion of a string of this form:


     #ifndef lint
     static char vcid[] = "STRING";
     #endif /* lint */

\1f
File: xemacs.info,  Node: ListDir,  Next: Comparing Files,  Prev: Version Control,  Up: Files

Listing a File Directory
========================

   Files are organized by Unix into "directories".  A "directory
listing" is a list of all the files in a directory.  Emacs provides
directory listings in brief format (file names only) and verbose format
(sizes, dates, and authors included).

`C-x C-d DIR-OR-PATTERN'
     Print a brief directory listing (`list-directory').

`C-u C-x C-d DIR-OR-PATTERN'
     Print a verbose directory listing.

   To print a directory listing, use `C-x C-d' (`list-directory').
This command prompts in the minibuffer for a file name which is either
a  directory to be listed or pattern containing wildcards for the files
to be listed.  For example,

     C-x C-d /u2/emacs/etc <RET>

lists all the files in directory `/u2/emacs/etc'.  An example of
specifying a file name pattern is:

     C-x C-d /u2/emacs/src/*.c <RET>

   Normally, `C-x C-d' prints a brief directory listing containing just
file names.  A numeric argument (regardless of value) tells it to print
a verbose listing (like `ls -l').

   Emacs obtains the text of a directory listing by running `ls' in an
inferior process.  Two Emacs variables control the switches passed to
`ls': `list-directory-brief-switches' is a string giving the switches
to use in brief listings (`"-CF"' by default).
`list-directory-verbose-switches' is a string giving the switches to
use in a verbose listing (`"-l"' by default).

   The variable `directory-abbrev-alist' is an alist of abbreviations
for file directories.  The list consists of elements of the form `(FROM
.  TO)', each meaning to replace `FROM' with `TO' when it appears in a
directory name.  This replacement is done when setting up the default
directory of a newly visited file.  Every `FROM' string should start
with ``^''.

   Use this feature when you have directories which you normally refer
to via absolute symbolic links.  Make `TO' the name of the link, and
`FROM' the name it is linked to.

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File: xemacs.info,  Node: Comparing Files,  Next: Dired,  Prev: ListDir,  Up: Files

Comparing Files
===============

   The command `M-x diff' compares two files, displaying the
differences in an Emacs buffer named `*Diff*'.  It works by running the
`diff' program, using options taken from the variable `diff-switches',
whose value should be a string.

   The buffer `*Diff*' has Compilation mode as its major mode, so you
can use `C-x `' to visit successive changed locations in the two source
files.  You can also move to a particular hunk of changes and type `C-c
C-c' to find the corresponding source location.  You can also use the
other special commands of Compilation mode: <SPC> and <DEL> for
scrolling, and `M-p' and `M-n' for cursor motion.  *Note Compilation::.

   The command `M-x diff-backup' compares a specified file with its most
recent backup.  If you specify the name of a backup file, `diff-backup'
compares it with the source file that it is a backup of.

   The command `M-x compare-windows' compares the text in the current
window with that in the next window.  Comparison starts at point in each
window.  Point moves forward in each window, a character at a time in
each window, until the next characters in the two windows are
different.  Then the command is finished.  For more information about
windows in Emacs, *Note Windows::.

   With a numeric argument, `compare-windows' ignores changes in
whitespace.  If the variable `compare-ignore-case' is non-`nil', it
ignores differences in case as well.

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File: xemacs.info,  Node: Dired,  Next: Misc File Ops,  Prev: Comparing Files,  Up: Files

Dired, the Directory Editor
===========================

   Dired makes it easy to delete or visit many of the files in a single
directory at once.  It creates an Emacs buffer containing a listing of
the directory.  You can use the normal Emacs commands to move around in
this buffer and special Dired commands to operate on the files.

* Menu:

* Enter: Dired Enter.         How to invoke Dired.
* Edit: Dired Edit.           Editing the Dired buffer.
* Deletion: Dired Deletion.   Deleting files with Dired.
* Immed: Dired Immed.         Other file operations through Dired.

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File: xemacs.info,  Node: Dired Enter,  Next: Dired Edit,  Prev: Dired,  Up: Dired

Entering Dired
--------------

   To invoke dired, type `C-x d' or `M-x dired'.  The command reads a
directory name or wildcard file name pattern as a minibuffer argument
just like the `list-directory' command, `C-x C-d'.  Where `dired'
differs from `list-directory' is in naming the buffer after the
directory name or the wildcard pattern used for the listing, and putting
the buffer into Dired mode so that the special commands of Dired are
available in it.  The variable `dired-listing-switches' is a string
used as an argument to `ls' in making the directory; this string must
contain `-l'.

   To display the Dired buffer in another window rather than in the
selected window, use `C-x 4 d' (`dired-other-window)' instead of `C-x
d'.

\1f
File: xemacs.info,  Node: Dired Edit,  Next: Dired Deletion,  Prev: Dired Enter,  Up: Dired

Editing in Dired
----------------

   Once the Dired buffer exists, you can switch freely between it and
other Emacs buffers.  Whenever the Dired buffer is selected, certain
special commands are provided that operate on files that are listed.
The Dired buffer is "read-only", and inserting text in it is not
useful, so ordinary printing characters such as `d' and `x' are used
for Dired commands.  Most Dired commands operate on the file described
by the line that point is on.  Some commands perform operations
immediately; others "flag" a file to be operated on later.

   Most Dired commands that operate on the current line's file also
treat a numeric argument as a repeat count, meaning to act on the files
of the next few lines.  A negative argument means to operate on the
files of the preceding lines, and leave point on the first of those
lines.

   All the usual Emacs cursor motion commands are available in Dired
buffers.  Some special purpose commands are also provided.  The keys
`C-n' and `C-p' are redefined so that they try to position the cursor
at the beginning of the filename on the line, rather than at the
beginning of the line.

   For extra convenience, <SPC> and `n' in Dired are equivalent to
`C-n'.  `p' is equivalent to `C-p'.  Moving by lines is done so often
in Dired that it deserves to be easy to type.  <DEL> (move up and
unflag) is often useful simply for moving up.

   The `g' command in Dired runs `revert-buffer' to reinitialize the
buffer from the actual disk directory and show any changes made in the
directory by programs other than Dired.  All deletion flags in the Dired
buffer are lost when this is done.

\1f
File: xemacs.info,  Node: Dired Deletion,  Next: Dired Immed,  Prev: Dired Edit,  Up: Dired

Deleting Files With Dired
-------------------------

   The primary use of Dired is to flag files for deletion and then
delete them.

`d'
     Flag this file for deletion.

`u'
     Remove deletion-flag on this line.

`<DEL>'
     Remove deletion-flag on previous line, moving point to that line.

`x'
     Delete the files that are flagged for deletion.

`#'
     Flag all auto-save files (files whose names start and end with `#')
     for deletion (*note Auto Save::).

`~'
     Flag all backup files (files whose names end with `~') for deletion
     (*note Backup::).

`. (Period)'
     Flag excess numeric backup files for deletion.  The oldest and
     newest few backup files of any one file are exempt; the middle
     ones are flagged.

   You can flag a file for deletion by moving to the line describing the
file and typing `d' or `C-d'.  The deletion flag is visible as a `D' at
the beginning of the line.  Point is moved to the beginning of the next
line, so that repeated `d' commands flag successive files.

   The files are flagged for deletion rather than deleted immediately to
avoid the danger of deleting a file accidentally.  Until you direct
Dired to delete the flagged files, you can remove deletion flags using
the commands `u' and <DEL>.  `u' works just like `d', but removes flags
rather than making flags.  <DEL> moves upward, removing flags; it is
like `u' with numeric argument automatically negated.

   To delete the flagged files, type `x'.  This command first displays a
list of all the file names flagged for deletion, and requests
confirmation with `yes'.  Once you confirm, all the flagged files are
deleted, and their lines are deleted from the text of the Dired buffer.
The shortened Dired buffer remains selected.  If you answer `no' or
quit with `C-g', you return immediately to Dired, with the deletion
flags still present and no files actually deleted.

   The `#', `~', and `.' commands flag many files for deletion, based
on their names.  These commands are useful precisely because they do
not actually delete any files; you can remove the deletion flags from
any flagged files that you really wish to keep.

   `#' flags for deletion all files that appear to have been made by
auto-saving (that is, files whose names begin and end with `#').  `~'
flags for deletion all files that appear to have been made as backups
for files that were edited (that is, files whose names end with `~').

   `.' (Period) flags just some of the backup files for deletion: only
numeric backups that are not among the oldest few nor the newest few
backups of any one file.  Normally `dired-kept-versions' (not
`kept-new-versions'; that applies only when saving) specifies the
number of newest versions of each file to keep, and `kept-old-versions'
specifies the number of oldest versions to keep.  Period with a
positive numeric argument, as in `C-u 3 .', specifies the number of
newest versions to keep, overriding `dired-kept-versions'.  A negative
numeric argument overrides `kept-old-versions', using minus the value
of the argument to specify the number of oldest versions of each file
to keep.

\1f
File: xemacs.info,  Node: Dired Immed,  Prev: Dired Deletion,  Up: Dired

Immediate File Operations in Dired
----------------------------------

   Some file operations in Dired take place immediately when they are
requested.

`C'
     Copies the file described on the current line.  You must supply a
     file name to copy to, using the minibuffer.

`f'
     Visits the file described on the current line.  It is just like
     typing `C-x C-f' and supplying that file name.  If the file on
     this line is a subdirectory, `f' actually causes Dired to be
     invoked on that subdirectory.  *Note Visiting::.

`o'
     Like `f', but uses another window to display the file's buffer.
     The Dired buffer remains visible in the first window.  This is
     like using `C-x 4 C-f' to visit the file.  *Note Windows::.

`R'
     Renames the file described on the current line.  You must supply a
     file name to rename to, using the minibuffer.

`v'
     Views the file described on this line using `M-x view-file'.
     Viewing a file is like visiting it, but is slanted toward moving
     around in the file conveniently and does not allow changing the
     file.  *Note View File: Misc File Ops.  Viewing a file that is a
     directory runs Dired on that directory.

\1f
File: xemacs.info,  Node: Misc File Ops,  Prev: Dired,  Up: Files

Miscellaneous File Operations
=============================

   Emacs has commands for performing many other operations on files.
All operate on one file; they do not accept wildcard file names.

   You can use the command `M-x add-name-to-file' to add a name to an
existing file without removing the old name.  The new name must belong
on the file system that the file is on.

   `M-x append-to-file' adds the text of the region to the end of the
specified file.

   `M-x copy-file' reads the file OLD and writes a new file named NEW
with the same contents.  Confirmation is required if a file named NEW
already exists, because copying overwrites the old contents of the file
NEW.

   `M-x delete-file' deletes a specified file, like the `rm' command in
the shell.  If you are deleting many files in one directory, it may be
more convenient to use Dired (*note Dired::).

   `M-x insert-file' inserts a copy of the contents of a specified file
into the current buffer at point, leaving point unchanged before the
contents and the mark after them.  *Note Mark::.

   `M-x make-symbolic-link' reads two file names OLD and LINKNAME, and
then creates a symbolic link named LINKNAME and pointing at OLD.
Future attempts to open file LINKNAME will then refer to the file named
OLD at the time the opening is done, or will result in an error if the
name OLD is not in use at that time.  Confirmation is required if you
create the link while LINKNAME is in use.  Note that not all systems
support symbolic links.

   `M-x rename-file' reads two file names OLD and NEW using the
minibuffer, then renames file OLD as NEW.  If a file named NEW already
exists, you must confirm with `yes' or renaming is not done; this is
because renaming causes the previous meaning of the name NEW to be
lost.  If OLD and NEW are on different file systems, the file OLD is
copied and deleted.

   `M-x view-file' allows you to scan or read a file by sequential
screenfuls.  It reads a file name argument using the minibuffer.  After
reading the file into an Emacs buffer, `view-file' reads and displays
one windowful.  You can then type <SPC> to scroll forward one window,
or <DEL> to scroll backward.  Various other commands are provided for
moving around in the file, but none for changing it; type `C-h' while
viewing a file for a list of them.  Most commands are the default Emacs
cursor motion commands.  To exit from viewing, type `C-c'.

\1f
File: xemacs.info,  Node: Buffers,  Next: Windows,  Prev: Files,  Up: Top

Using Multiple Buffers
**********************

   Text you are editing in Emacs resides in an object called a
"buffer".  Each time you visit a file, Emacs creates a buffer to hold
the file's text.  Each time you invoke Dired, Emacs creates a buffer to
hold the directory listing.  If you send a message with `C-x m', a
buffer named `*mail*' is used to hold the text of the message.  When
you ask for a command's documentation, it appears in a buffer called
`*Help*'.

   At any time, one and only one buffer is "selected".  It is also
called the "current buffer".  Saying a command operates on "the buffer"
really means that the command operates on the selected buffer, as most
commands do.

   When Emacs creates multiple windows, each window has a chosen buffer
which is displayed there, but at any time only one of the windows is
selected and its chosen buffer is the selected buffer.  Each window's
mode line displays the name of the buffer the window is displaying
(*note Windows::).

   Each buffer has a name which can be of any length but is
case-sensitive.  You can select a buffer using its name.  Most buffers
are created when you visit files; their names are derived from the
files' names.  You can also create an empty buffer with any name you
want.  A newly started Emacs has a buffer named `*scratch*' which you
can use for evaluating Lisp expressions in Emacs.

   Each buffer records what file it is visiting, whether it is
modified, and what major mode and minor modes are in effect in it
(*note Major Modes::).  Any Emacs variable can be made "local to" a
particular buffer, meaning its value in that buffer can be different
from the value in other buffers.  *Note Locals::.

* Menu:

* Select Buffer::   Creating a new buffer or reselecting an old one.
* List Buffers::    Getting a list of buffers that exist.
* Misc Buffer::     Renaming; changing read-onliness; copying text.
* Kill Buffer::     Killing buffers you no longer need.
* Several Buffers:: How to go through the list of all buffers
                     and operate variously on several of them.

\1f
File: xemacs.info,  Node: Select Buffer,  Next: List Buffers,  Prev: Buffers,  Up: Buffers

Creating and Selecting Buffers
==============================

`C-x b BUFFER <RET>'
     Select or create a buffer named BUFFER (`switch-to-buffer').

`C-x 4 b BUFFER <RET>'
     Similar, but select a buffer named BUFFER in another window
     (`switch-to-buffer-other-window').

`M-x switch-to-other-buffer N'
     Switch to the previous buffer.

   To select a buffer named BUFNAME, type `C-x b BUFNAME <RET>'.  This
is the command `switch-to-buffer' with argument BUFNAME.  You can use
completion on an abbreviation for the buffer name you want (*note
Completion::).  An empty argument to `C-x b' specifies the most
recently selected buffer that is not displayed in any window.

   Most buffers are created when you visit files, or use Emacs commands
that display text.  You can also create a buffer explicitly by typing
`C-x b BUFNAME <RET>', which creates a new, empty buffer that is not
visiting any file, and selects it for editing.  The new buffer's major
mode is determined by the value of `default-major-mode' (*note Major
Modes::).  Buffers not visiting files are usually used for making notes
to yourself.  If you try to save one, you are asked for the file name
to use.

   The function `switch-to-buffer-other-frame' is similar to
`switch-to-buffer' except that it creates a new frame in which to
display the selected buffer.

   Use `M-x switch-to-other-buffer' to visit the previous buffer. If
you supply a positive integer N, the Nth most recent buffer is
displayed. If you supply an argument of 0, the current buffer is moved
to the bottom of the buffer stack.

   Note that you can also use `C-x C-f' and any other command for
visiting a file to switch buffers.  *Note Visiting::.

\1f
File: xemacs.info,  Node: List Buffers,  Next: Misc Buffer,  Prev: Select Buffer,  Up: Buffers

Listing Existing Buffers
========================

`C-x C-b'
     List the existing buffers (`list-buffers').

   To print a list of all existing buffers, type `C-x C-b'.  Each line
in the list shows one buffer's name, major mode, and visited file.  A
`*' at the beginning of a line indicates the buffer has been
"modified".  If several buffers are modified, it may be time to save
some with `C-x s' (*note Saving::).  A `%' indicates a read-only
buffer.  A `.' marks the selected buffer.  Here is an example of a
buffer list:

      MR Buffer         Size  Mode           File
      -- ------         ----  ----           ----
     .*  emacs.tex      383402 Texinfo       /u2/emacs/man/emacs.tex
         *Help*         1287  Fundamental
         files.el       23076 Emacs-Lisp     /u2/emacs/lisp/files.el
       % RMAIL          64042 RMAIL          /u/rms/RMAIL
      *% man            747   Dired             /u2/emacs/man/
         net.emacs      343885 Fundamental   /u/rms/net.emacs
         fileio.c       27691 C              /u2/emacs/src/fileio.c
         NEWS           67340 Text           /u2/emacs/etc/NEWS
         *scratch*         0     Lisp Interaction

Note that the buffer `*Help*' was made by a help request; it is not
visiting any file.  The buffer `man' was made by Dired on the directory
`/u2/emacs/man/'.

   As you move the mouse over the `*Buffer List*' buffer, the lines are
highlighted.  This visual cue indicates that clicking the right mouse
button (`button3') will pop up a menu of commands on the buffer
represented by this line.  This menu duplicates most of those commands
which are bound to keys in the `*Buffer List*' buffer.

\1f
File: xemacs.info,  Node: Misc Buffer,  Next: Kill Buffer,  Prev: List Buffers,  Up: Buffers

Miscellaneous Buffer Operations
===============================

`C-x C-q'
     Toggle read-only status of buffer (`toggle-read-only').

`M-x rename-buffer'
     Change the name of the current buffer.

`M-x view-buffer'
     Scroll through a buffer.

   A buffer can be "read-only", which means that commands to change its
text are not allowed.  Normally, read-only buffers are created by
subsystems such as Dired and Rmail that have special commands to operate
on the text.  Emacs also creates a read-only buffer if you visit a file
that is protected.  To make changes in a read-only buffer, use the
command `C-x C-q' (`toggle-read-only').  It makes a read-only buffer
writable, and makes a writable buffer read-only.  This works by setting
the variable `buffer-read-only', which has a local value in each buffer
and makes a buffer read-only if its value is non-`nil'.

   `M-x rename-buffer' changes the name of the current buffer,
prompting for the new name in the minibuffer.  There is no default.  If
you specify a name that is used by a different buffer, an error is
signalled and renaming is not done.

   `M-x view-buffer' is similar to `M-x view-file' (*note Misc File
Ops::), but it examines an already existing Emacs buffer.  View mode
provides convenient commands for scrolling through the buffer but not
for changing it.  When you exit View mode, the resulting value of point
remains in effect.

   To copy text from one buffer to another, use the commands `M-x
append-to-buffer' and `M-x insert-buffer'.  *Note Accumulating Text::.

\1f
File: xemacs.info,  Node: Kill Buffer,  Next: Several Buffers,  Prev: Misc Buffer,  Up: Buffers

Killing Buffers
===============

   After using Emacs for a while, you may accumulate a large number of
buffers and may want to eliminate the ones you no longer need.  There
are several commands for doing this.

`C-x k'
     Kill a buffer, specified by name (`kill-buffer').

`M-x kill-some-buffers'
     Offer to kill each buffer, one by one.

   `C-x k' (`kill-buffer') kills one buffer, whose name you specify in
the minibuffer.  If you type just <RET> in the minibuffer, the default,
killing the current buffer, is used.  If the current buffer is killed,
the buffer that has been selected recently but does not appear in any
window now is selected.  If the buffer being killed contains unsaved
changes, you are asked to confirm with `yes' before the buffer is
killed.

   The command `M-x kill-some-buffers' asks about each buffer, one by
one.  An answer of `y' means to kill the buffer.  Killing the current
buffer or a buffer containing unsaved changes selects a new buffer or
asks for confirmation just like `kill-buffer'.

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File: xemacs.info,  Node: Several Buffers,  Prev: Kill Buffer,  Up: Buffers

Operating on Several Buffers
============================

   The "buffer-menu" facility is like a "Dired for buffers"; it allows
you to request operations on various Emacs buffers by editing a buffer
containing a list of them.  You can save buffers, kill them (here
called "deleting" them, for consistency with Dired), or display them.

`M-x buffer-menu'
     Begin editing a buffer listing all Emacs buffers.

   The command `buffer-menu' writes a list of all Emacs buffers into
the buffer `*Buffer List*', and selects that buffer in Buffer Menu
mode.  The buffer is read-only.  You can only change it using the
special commands described in this section.  Most of the commands are
graphic characters.  You can use  Emacs cursor motion commands in the
`*Buffer List*' buffer.  If the cursor is on a line describing a
buffer, the following  special commands apply to that buffer:

`d'
     Request to delete (kill) the buffer, then move down.  A `D' before
     the buffer name on a line indicates a deletion request.  Requested
     deletions actually take place when you use the `x' command.

`k'
     Synonym for `d'.

`C-d'
     Like `d' but move up afterwards instead of down.

`s'
     Request to save the buffer.  An `S' befor the buffer name on a line
     indicates the request.  Requested saves actually take place when
     you use the `x' command.  You can request both saving and deletion
     for the same buffer.

`~'
     Mark buffer "unmodified".  The command `~' does this immediately
     when typed.

`x'
     Perform previously requested deletions and saves.

`u'
     Remove any request made for the current line, and move down.

`<DEL>'
     Move to previous line and remove any request made for that line.

   All commands that add or remove flags to request later operations
also move down a line.  They accept a numeric argument as a repeat
count, unless otherwise specified.

   There are also special commands to use the buffer list to select
another buffer, and to specify one or more other buffers for display in
additional windows.

`1'
     Select the buffer in a full-frame window.  This command takes
     effect immediately.

`2'
     Immediately set up two windows, with this buffer in one and the
     buffer selected before `*Buffer List*' in the other.

`f'
     Immediately select the buffer in place of the `*Buffer List*'
     buffer.

`o'
     Immediately select the buffer in another window as if by `C-x 4 b',
     leaving `*Buffer List*' visible.

`q'
     Immediately select this buffer, and display any buffers previously
     flagged with the `m' command in other windows.  If there are no
     buffers flagged with `m', this command is equivalent to `1'.

`m'
     Flag this buffer to be displayed in another window if the `q'
     command is used.  The request shows as a `>' at the beginning of
     the line.  The same buffer may not have both a delete request and a
     display request.

   Going back between a `buffer-menu' buffer and other Emacs buffers is
easy.  You can, for example, switch from the `*Buffer List*' buffer to
another Emacs buffer, and edit there.  You can then reselect the
`buffer-menu' buffer and perform operations already requested, or you
can kill that buffer or pay no further attention to it.   All that
`buffer-menu' does directly is create and select a suitable buffer, and
turn on Buffer Menu mode.  All the other capabilities of the buffer
menu are implemented by special commands provided in Buffer Menu mode.

   The only difference between `buffer-menu' and `list-buffers' is that
`buffer-menu' selects the `*Buffer List*' buffer and `list-buffers'
does not.  If you run `list-buffers' (that is, type `C-x C-b') and
select the buffer list manually, you can use all the commands described
here.

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File: xemacs.info,  Node: Windows,  Next: Mule,  Prev: Buffers,  Up: Top

Multiple Windows
****************

   Emacs can split the frame into two or many windows, which can display
parts of different buffers or different parts of one buffer.  If you are
running XEmacs under X, that means you can have the X window that
contains the Emacs frame have multiple subwindows.

* Menu:

* Basic Window::     Introduction to Emacs windows.
* Split Window::     New windows are made by splitting existing windows.
* Other Window::     Moving to another window or doing something to it.
* Pop Up Window::    Finding a file or buffer in another window.
* Change Window::    Deleting windows and changing their sizes.

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File: xemacs.info,  Node: Basic Window,  Next: Split Window,  Prev: Windows,  Up: Windows

Concepts of Emacs Windows
=========================

   When Emacs displays multiple windows, each window has one Emacs
buffer designated for display.  The same buffer may appear in more than
one window; if it does, any changes in its text are displayed in all
the windows that display it.  Windows showing the same buffer can show
different parts of it, because each window has its own value of point.

   At any time, one  window is the "selected window"; the buffer
displayed by that window is the current buffer.  The cursor shows the
location of point in that window.  Each other window has a location of
point as well, but since the terminal has only one cursor, it cannot
show the location of point in the other windows.

   Commands to move point affect the value of point for the selected
Emacs window only.  They do not change the value of point in any other
Emacs window, including those showing the same buffer.  The same is
true for commands such as `C-x b' to change the selected buffer in the
selected window; they do not affect other windows at all.  However,
there are other commands such as `C-x 4 b' that select a different
window and switch buffers in it.  Also, all commands that display
information in a window, including (for example) `C-h f'
(`describe-function') and `C-x C-b' (`list-buffers'), work by switching
buffers in a non-selected window without affecting the selected window.

   Each window has its own mode line, which displays the buffer name,
modification status, and major and minor modes of the buffer that is
displayed in the window.  *Note Mode Line::, for details on the mode
line.

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File: xemacs.info,  Node: Split Window,  Next: Other Window,  Prev: Basic Window,  Up: Windows

Splitting Windows
=================

`C-x 2'
     Split the selected window into two windows, one above the other
     (`split-window-vertically').

`C-x 3'
     Split the selected window into two windows positioned side by side
     (`split-window-horizontally').

`C-x 6'
     Save the current window configuration in register REG (a letter).

`C-x 7'
     Restore (make current) the window configuration in register REG (a
     letter).  Use with a register previously set with `C-x 6'.

   The command `C-x 2' (`split-window-vertically') breaks the selected
window into two windows, one above the other.  Both windows start out
displaying the same buffer, with the same value of point.  By default
each of the two windows gets half the height of the window that was
split.  A numeric argument specifies how many lines to give to the top
window.

   `C-x 3' (`split-window-horizontally') breaks the selected window
into two side-by-side windows.  A numeric argument specifies how many
columns to give the one on the left.  A line of vertical bars separates
the two windows.  Windows that are not the full width of the frame have
truncated mode lines which do not always appear in inverse video,
because Emacs display routines cannot display a region of inverse video
that is only part of a line on the screen.

   When a window is less than the full width, many text lines are too
long to fit.  Continuing all those lines might be confusing.  Set the
variable `truncate-partial-width-windows' to non-`nil' to force
truncation in all windows less than the full width of the frame,
independent of the buffer and its value for `truncate-lines'.  *Note
Continuation Lines::.

   Horizontal scrolling is often used in side-by-side windows.  *Note
Display::.

   You can resize a window and store that configuration in a register by
supplying a REGISTER argument to `window-configuration-to-register'
(`C-x 6'). To return to the window configuration established with
`window-configuration-to-register', use `jump-to-register' (`C-x j').

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File: xemacs.info,  Node: Other Window,  Next: Pop Up Window,  Prev: Split Window,  Up: Windows

Using Other Windows
===================

`C-x o'
     Select another window (`other-window').  That is the letter `o',
     not zero.

`M-C-v'
     Scroll the next window (`scroll-other-window').

`M-x compare-windows'
     Find the next place where the text in the selected window does not
     match the text in the next window.

`M-x other-window-any-frame N'
     Select the Nth different window on any frame.

   To select a different window, use `C-x o' (`other-window').  That is
an `o', for `other', not a zero.  When there are more than two windows,
the command moves through all the windows in a cyclic order, generally
top to bottom and left to right.  From the rightmost and bottommost
window, it goes back to the one at the upper left corner.  A numeric
argument, N, moves several steps in the cyclic order of windows. A
negative numeric argument moves around the cycle in the opposite order.
If the optional second argument ALL-FRAMES is non-`nil', the function
cycles through all frames.  When the minibuffer is active, the
minibuffer is the last window in the cycle; you can switch from the
minibuffer window to one of the other windows, and later switch back
and finish supplying the minibuffer argument that is requested.  *Note
Minibuffer Edit::.

   The command `M-x other-window-any-frame' also selects the window N
steps away in the cyclic order.  However, unlike `other-window', this
command selects a window on the next or previous frame instead of
wrapping around to the top or bottom of the current frame, when there
are no more windows.

   The usual scrolling commands (*note Display::) apply to the selected
window only.  `M-C-v' (`scroll-other-window') scrolls the window that
`C-x o' would select.  Like `C-v', it takes positive and negative
arguments.

   The command `M-x compare-windows' compares the text in the current
window with the text in the next window.  Comparison starts at point in
each window.  Point moves forward in each window, a character at a time,
until the next set of characters in the two windows are different.
Then the command is finished.

   A prefix argument IGNORE-WHITESPACE means ignore changes in
whitespace.  The variable `compare-windows-whitespace' controls how
whitespace is skipped.

   If `compare-ignore-case' is non-`nil', changes in case are also
ignored.

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File: xemacs.info,  Node: Pop Up Window,  Next: Change Window,  Prev: Other Window,  Up: Windows

Displaying in Another Window
============================

   `C-x 4' is a prefix key for commands that select another window
(splitting the window if there is only one) and select a buffer in that
window.  Different `C-x 4' commands have different ways of finding the
buffer to select.

`C-x 4 b BUFNAME <RET>'
     Select buffer BUFNAME in another window.  This runs
     `switch-to-buffer-other-window'.

`C-x 4 f FILENAME <RET>'
     Visit file FILENAME and select its buffer in another window.  This
     runs `find-file-other-window'.  *Note Visiting::.

`C-x 4 d DIRECTORY <RET>'
     Select a Dired buffer for directory DIRECTORY in another window.
     This runs `dired-other-window'.  *Note Dired::.

`C-x 4 m'
     Start composing a mail message in another window.  This runs
     `mail-other-window', and its same-window version is `C-x m' (*note
     Sending Mail::).

`C-x 4 .'
     Find a tag in the current tag table in another window.  This runs
     `find-tag-other-window', the multiple-window variant of `M-.'
     (*note Tags::).

   If the variable `display-buffer-function' is non-`nil', its value is
the function to call to handle `display-buffer'. It receives two
arguments, the buffer and a flag that if non-`nil' means that the
currently selected window is not acceptable. Commands such as
`switch-to-buffer-other-window' and `find-file-other-window' work using
this function.

\1f
File: xemacs.info,  Node: Change Window,  Prev: Pop Up Window,  Up: Windows

Deleting and Rearranging Windows
================================

`C-x 0'
     Get rid of the selected window (`delete-window').  That is a zero.
     If there is more than one Emacs frame, deleting the sole remaining
     window on that frame deletes the frame as well. If the current
     frame is the only frame, it is not deleted.

`C-x 1'
     Get rid of all windows except the selected one
     (`delete-other-windows').

`C-x ^'
     Make the selected window taller, at the expense of the other(s)
     (`enlarge-window').

`C-x }'
     Make the selected window wider (`enlarge-window-horizontally').

   To delete a window, type `C-x 0' (`delete-window').  (That is a
zero.)  The space occupied by the deleted window is distributed among
the other active windows (but not the minibuffer window, even if that
is active at the time).  Once a window is deleted, its attributes are
forgotten; there is no automatic way to make another window of the same
shape or showing the same buffer.  The buffer continues to exist, and
you can select it in any window with `C-x b'.

   `C-x 1' (`delete-other-windows') is more powerful than `C-x 0'; it
deletes all the windows except the selected one (and the minibuffer).
The selected window expands to use the whole frame except for the echo
area.

   To readjust the division of space among existing windows, use `C-x
^' (`enlarge-window').  It makes the currently selected window longer
by one line or as many lines as a numeric argument specifies.  With a
negative argument, it makes the selected window smaller.  `C-x }'
(`enlarge-window-horizontally') makes the selected window wider by the
specified number of columns.  The extra screen space given to a window
comes from one of its neighbors, if that is possible; otherwise, all
the competing windows are shrunk in the same proportion.  If this makes
some windows too small, those windows are deleted and their space is
divided up.   Minimum window size is specified by the variables
`window-min-height' and `window-min-width'.

   You can also resize windows within a frame by clicking the left mouse
button on a modeline, and dragging.

   Clicking the right button on a mode line pops up a menu of common
window manager operations.  This menu contains the following options:

Delete Window
     Remove the window above this modeline from the frame.

Delete Other Windows
     Delete all windows on the frame except for the one above this
     modeline.

Split Window
     Split the window above the mode line in half, creating another
     window.

Split Window Horizontally
     Split the window above the mode line in half horizontally, so that
     there will be two windows side-by-side.

Balance Windows
     Readjust the sizes of all windows on the frame until all windows
     have roughly the same number of lines.

\1f
File: xemacs.info,  Node: Mule,  Next: Major Modes,  Prev: Windows,  Up: Top

World Scripts Support
*********************

   If you compile XEmacs with mule option, it supports a wide variety of
world scripts, including Latin script, as well as Arabic script,
Simplified Chinese script (for mainland of China), Traditional Chinese
script (for Taiwan and Hong-Kong), Greek script, Hebrew script, IPA
symbols, Japanese scripts (Hiragana, Katakana and Kanji), Korean scripts
(Hangul and Hanja) and Cyrillic script (for Beylorussian, Bulgarian,
Russian, Serbian and Ukrainian).  These features have been merged from
the modified version of Emacs known as MULE (for "MULti-lingual
Enhancement to GNU Emacs").

* Menu:

* Mule Intro::              Basic concepts of Mule.
* Language Environments::   Setting things up for the language you use.
* Input Methods::           Entering text characters not on your keyboard.
* Select Input Method::     Specifying your choice of input methods.
* Coding Systems::          Character set conversion when you read and
                              write files, and so on.
* Recognize Coding::        How XEmacs figures out which conversion to use.
* Specify Coding::          Various ways to choose which conversion to use.

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File: xemacs.info,  Node: Mule Intro,  Next: Language Environments,  Prev: Mule,  Up: Mule

Introduction to world scripts
=============================

   The users of these scripts have established many more-or-less
standard coding systems for storing files.  XEmacs translates between
the internal character encoding and various other coding systems when
reading and writing files, when exchanging data with subprocesses, and
(in some cases) in the `C-q' command (see below).

   The command `C-h h' (`view-hello-file') displays the file
`etc/HELLO', which shows how to say "hello" in many languages.  This
illustrates various scripts.

   Keyboards, even in the countries where these character sets are used,
generally don't have keys for all the characters in them.  So XEmacs
supports various "input methods", typically one for each script or
language, to make it convenient to type them.

   The prefix key `C-x <RET>' is used for commands that pertain to
world scripts, coding systems, and input methods.

\1f
File: xemacs.info,  Node: Language Environments,  Next: Input Methods,  Prev: Mule Intro,  Up: Mule

Language Environments
=====================

   All supported character sets are supported in XEmacs buffers if it is
compile with mule; there is no need to select a particular language in
order to display its characters in an XEmacs buffer.  However, it is
important to select a "language environment" in order to set various
defaults.  The language environment really represents a choice of
preferred script (more or less) rather that a choice of language.

   The language environment controls which coding systems to recognize
when reading text (*note Recognize Coding::).  This applies to files,
incoming mail, netnews, and any other text you read into XEmacs.  It may
also specify the default coding system to use when you create a file.
Each language environment also specifies a default input method.

   The command to select a language environment is `M-x
set-language-environment'.  It makes no difference which buffer is
current when you use this command, because the effects apply globally to
the XEmacs session.  The supported language environments include:

     Chinese-BIG5, Chinese-CNS, Chinese-GB, Cyrillic-ISO, English,
     Ethiopic, Greek, Japanese, Korean, Latin-1, Latin-2, Latin-3,
     Latin-4, Latin-5.

   Some operating systems let you specify the language you are using by
setting locale environment variables.  XEmacs handles one common special
case of this: if your locale name for character types contains the
string `8859-N', XEmacs automatically selects the corresponding
language environment.

   To display information about the effects of a certain language
environment LANG-ENV, use the command `C-h L LANG-ENV <RET>'
(`describe-language-environment').  This tells you which languages this
language environment is useful for, and lists the character sets,
coding systems, and input methods that go with it.  It also shows some
sample text to illustrate scripts used in this language environment.
By default, this command describes the chosen language environment.