-This is Info file ../../info/xemacs.info, produced by Makeinfo version
-1.68 from the input file xemacs.texi.
+This is ../info/xemacs.info, produced by makeinfo version 4.0b from
+xemacs/xemacs.texi.
INFO-DIR-SECTION XEmacs Editor
START-INFO-DIR-ENTRY
translation approved by the author instead of in the original English.
\1f
-File: xemacs.info, Node: Dired Immed, Prev: Dired Deletion, Up: Dired
+File: xemacs.info, Node: Backup Deletion, Next: Backup Copying, Prev: Backup Names, Up: Backup
-Immediate File Operations in Dired
-----------------------------------
+Automatic Deletion of Backups
+.............................
- Some file operations in Dired take place immediately when they are
-requested.
+ To prevent unlimited consumption of disk space, Emacs can delete
+numbered backup versions automatically. Generally Emacs keeps the
+first few backups and the latest few backups, deleting any in between.
+This happens every time a new backup is made. The two variables that
+control the deletion are `kept-old-versions' and `kept-new-versions'.
+Their values are, respectively the number of oldest (lowest-numbered)
+backups to keep and the number of newest (highest-numbered) ones to
+keep, each time a new backup is made. The values are used just after a
+new backup version is made; that newly made backup is included in the
+count in `kept-new-versions'. By default, both variables are 2.
-`C'
- Copies the file described on the current line. You must supply a
- file name to copy to, using the minibuffer.
+ If `delete-old-versions' is non-`nil', excess middle versions are
+deleted without notification. If it is `nil', the default, you are
+asked whether the excess middle versions should really be deleted.
-`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::.
+ You can also use Dired's `.' (Period) command to delete old versions.
+*Note Dired::.
-`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::.
+\1f
+File: xemacs.info, Node: Backup Copying, Prev: Backup Deletion, Up: Backup
+
+Copying vs. Renaming
+....................
+
+ You can make backup files by copying the old file or by renaming it.
+This makes a difference when the old file has multiple names. If you
+rename the old file into the backup file, the alternate names become
+names for the backup file. If you copy the old file instead, the
+alternate names remain names for the file that you are editing, and the
+contents accessed by those names will be the new contents.
+
+ How you make a backup file may also affect the file's owner and
+group. If you use copying, they do not change. If renaming is used,
+you become the file's owner, and the file's group becomes the default
+(different operating systems have different defaults for the group).
+
+ Having the owner change is usually a good idea, because then the
+owner is always the person who last edited the file. Occasionally
+there is a file whose owner should not change. Since most files should
+change owners, it is a good idea to use local variable lists to set
+`backup-by-copying-when-mismatch' for the special cases where the owner
+should not change (*note File Variables::).
+
+ Three variables control the choice of renaming or copying.
+Normally, renaming is done. If the variable `backup-by-copying' is
+non-`nil', copying is used. Otherwise, if the variable
+`backup-by-copying-when-linked' is non-`nil', copying is done for files
+that have multiple names, but renaming may still be done when the file
+being edited has only one name. If the variable
+`backup-by-copying-when-mismatch' is non-`nil', copying is done if
+renaming would cause the file's owner or group to change.
+
+\1f
+File: xemacs.info, Node: Interlocking, Prev: Backup, Up: Saving
+
+Protection Against Simultaneous Editing
+---------------------------------------
+
+ Simultaneous editing occurs when two users visit the same file, both
+make changes, and both save their changes. If no one was informed that
+this was happening, and you saved first, you would later find that your
+changes were lost. On some systems, Emacs notices immediately when the
+second user starts to change a file already being edited, and issues a
+warning. When this is not possible, or if the second user has started
+to change the file despite the warning, Emacs checks when the file is
+saved, and issues a second warning when a user is about to overwrite a
+file containing another user's changes. If you are the user editing the
+file, you can take corrective action at this point and prevent actual
+loss of work.
+
+ When you make the first modification in an Emacs buffer that is
+visiting a file, Emacs records that you have locked the file. (It does
+this by writing another file in a directory reserved for this purpose.)
+The lock is removed when you save the changes. The idea is that the
+file is locked whenever the buffer is modified. If you begin to modify
+the buffer while the visited file is locked by someone else, this
+constitutes a collision, and Emacs asks you what to do. It does this
+by calling the Lisp function `ask-user-about-lock', which you can
+redefine to customize what it does. The standard definition of this
+function asks you a question and accepts three possible answers:
-`R'
- Renames the file described on the current line. You must supply a
- file name to rename to, using the minibuffer.
+`s'
+ Steal the lock. Whoever was already changing the file loses the
+ lock, and you get the lock.
+
+`p'
+ Proceed. Go ahead and edit the file despite its being locked by
+ someone else.
-`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.
+`q'
+ Quit. This causes an error (`file-locked') and the modification
+ you were trying to make in the buffer does not actually take place.
+
+ Note that locking works on the basis of a file name; if a file has
+multiple names, Emacs does not realize that the two names are the same
+file and cannot prevent two users from editing it simultaneously under
+different names. However, basing locking on names means that Emacs can
+interlock the editing of new files that do not really exist until they
+are saved.
+
+ Some systems are not configured to allow Emacs to make locks. On
+these systems, Emacs cannot detect trouble in advance, but it can still
+detect it in time to prevent you from overwriting someone else's
+changes.
+
+ Every time Emacs saves a buffer, it first checks the
+last-modification date of the existing file on disk to see that it has
+not changed since the file was last visited or saved. If the date does
+not match, it implies that changes were made in the file in some other
+way, and these changes are about to be lost if Emacs actually does
+save. To prevent this, Emacs prints a warning message and asks for
+confirmation before saving. Occasionally you will know why the file
+was changed and know that it does not matter; then you can answer `yes'
+and proceed. Otherwise, you should cancel the save with `C-g' and
+investigate the situation.
+
+ The first thing you should do when notified that simultaneous editing
+has already taken place is to list the directory with `C-u C-x C-d'
+(*note Directory Listing: ListDir.). This will show the file's current
+author. You should attempt to contact that person and ask him not to
+continue editing. Often the next step is to save the contents of your
+Emacs buffer under a different name, and use `diff' to compare the two
+files.
+
+ Simultaneous editing checks are also made when you visit a file that
+is already visited with `C-x C-f' and when you start to modify a file.
+This is not strictly necessary, but it is useful to find out about such
+a problem as early as possible, when corrective action takes less work.
+
+ Another way to protect your file is to set the read, write, and
+executable permissions for the file. Use the function
+`set-default-file-modes' to set the UNIX `umask' value to the NMASK
+argument. The `umask' value is the default protection mode for new
+files.
\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'.
+File: xemacs.info, Node: Reverting, Next: Auto Save, Prev: Saving, Up: Files
+
+Reverting a Buffer
+==================
+
+ If you have made extensive changes to a file and then change your
+mind about them, you can get rid of all changes by reading in the
+previous version of the file. To do this, use `M-x revert-buffer',
+which operates on the current buffer. Since reverting a buffer can
+result in very extensive changes, you must confirm it with `yes'.
+
+ If the current buffer has been auto-saved more recently than it has
+been saved explicitly, `revert-buffer' offers to read the auto save file
+instead of the visited file (*note Auto Save::). Emacs asks you about
+the auto-save file before the request for confirmation of the
+`revert-buffer' operation, and demands `y' or `n' as an answer. If you
+have started to type `yes' for confirmation without realizing that the
+auto-save question was going to be asked, the `y' will answer that
+question, but the `es' will not be valid confirmation. This gives you
+a chance to cancel the operation with `C-g' and try again with the
+answers you really intend.
+
+ `revert-buffer' keeps point at the same distance (measured in
+characters) from the beginning of the file. If the file was edited only
+slightly, you will be at approximately the same piece of text after
+reverting as before. If you have made more extensive changes, the
+value of point in the old file may bring you to a totally different
+piece of text than your last editing point.
+
+ A buffer reverted from its visited file is marked "not modified"
+until you make a change.
+
+ Some kinds of buffers whose contents reflect data bases other than
+files, such as Dired buffers, can also be reverted. For them,
+reverting means recalculating their contents from the appropriate data.
+Buffers created randomly with `C-x b' cannot be reverted;
+`revert-buffer' reports an error when asked to do so.
\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::.
+File: xemacs.info, Node: Auto Save, Next: Version Control, Prev: Reverting, Up: Files
-* Menu:
+Auto-Saving: Protection Against Disasters
+=========================================
-* 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.
+ Emacs saves all the visited files from time to time (based on
+counting your keystrokes) without being asked. This is called
+"auto-saving". It prevents you from losing more than a limited amount
+of work if the system crashes.
-\1f
-File: xemacs.info, Node: Select Buffer, Next: List Buffers, Prev: Buffers, Up: Buffers
+ When Emacs determines it is time for auto-saving, each buffer is
+considered and is auto-saved if auto-saving is turned on for it and it
+has changed since the last time it was auto-saved. If any auto-saving
+is done, the message `Auto-saving...' is displayed in the echo area
+until auto-saving is finished. Errors occurring during auto-saving are
+caught so that they do not interfere with the execution of commands you
+have been typing.
+
+* Menu:
-Creating and Selecting Buffers
-==============================
+* Files: Auto Save Files.
+* Control: Auto Save Control.
+* Recover:: Recovering text from auto-save files.
-`C-x b BUFFER <RET>'
- Select or create a buffer named BUFFER (`switch-to-buffer').
+\1f
+File: xemacs.info, Node: Auto Save Files, Next: Auto Save Control, Prev: Auto Save, Up: Auto Save
+
+Auto-Save Files
+---------------
+
+ Auto-saving does not normally write to the files you visited, because
+it can be undesirable to save a program that is in an inconsistent
+state when you have made only half of a planned change. Instead,
+auto-saving is done in a different file called the "auto-save file",
+and the visited file is changed only when you save explicitly, for
+example, with `C-x C-s'.
+
+ Normally, the name of the auto-save file is generated by appending
+`#' to the front and back of the visited file name. Thus, a buffer
+visiting file `foo.c' would be auto-saved in a file `#foo.c#'. Most
+buffers that are not visiting files are auto-saved only if you request
+it explicitly; when they are auto-saved, the auto-save file name is
+generated by appending `#%' to the front and `#' to the back of buffer
+name. For example, the `*mail*' buffer in which you compose messages
+to be sent is auto-saved in a file named `#%*mail*#'. Names of
+auto-save files are generated this way unless you customize the
+functions `make-auto-save-file-name' and `auto-save-file-name-p' to do
+something different. The file name to be used for auto-saving a buffer
+is calculated at the time auto-saving is turned on in that buffer.
+
+ If you want auto-saving to be done in the visited file, set the
+variable `auto-save-visited-file-name' to be non-`nil'. In this mode,
+there is really no difference between auto-saving and explicit saving.
+
+ Emacs deletes a buffer's auto-save file when you explicitly save the
+buffer. To inhibit the deletion, set the variable
+`delete-auto-save-files' to `nil'. Changing the visited file name with
+`C-x C-w' or `set-visited-file-name' renames any auto-save file to
+correspond to the new visited name.
-`C-x 4 b BUFFER <RET>'
- Similar, but select a buffer named BUFFER in another window
- (`switch-to-buffer-other-window').
+\1f
+File: xemacs.info, Node: Auto Save Control, Next: Recover, Prev: Auto Save Files, Up: Auto Save
+
+Controlling Auto-Saving
+-----------------------
+
+ Each time you visit a file, auto-saving is turned on for that file's
+buffer if the variable `auto-save-default' is non-`nil' (but not in
+batch mode; *note Entering Emacs::). The default for this variable is
+`t', so Emacs auto-saves buffers that visit files by default. You can
+use the command `M-x auto-save-mode' to turn auto-saving for a buffer
+on or off. Like other minor mode commands, `M-x auto-save-mode' turns
+auto-saving on with a positive argument, off with a zero or negative
+argument; with no argument, it toggles.
+
+ Emacs performs auto-saving periodically based on counting how many
+characters you have typed since the last time auto-saving happened. The
+variable `auto-save-interval' specifies the number of characters
+between auto-saves. By default, it is 300. Emacs also auto-saves
+whenever you call the function `do-auto-save'.
+
+ Emacs also does auto-saving whenever it gets a fatal error. This
+includes killing the Emacs job with a shell command such as `kill
+-emacs', or disconnecting a phone line or network connection.
+
+ You can set the number of seconds of idle time before an auto-save is
+done. Setting the value of the variable `auto-save-timeout' to zero or
+`nil' will disable auto-saving due to idleness.
+
+ The actual amount of idle time between auto-saves is logarithmically
+related to the size of the current buffer. This variable is the number
+of seconds after which an auto-save will happen when the current buffer
+is 50k or less; the timeout will be 2 1/4 times this in a 200k buffer, 3
+3/4 times this in a 1000k buffer, and 4 1/2 times this in a 2000k
+buffer.
+
+ For this variable to have any effect, you must do `(require 'timer)'.
-`M-x switch-to-other-buffer N'
- Switch to the previous buffer.
+\1f
+File: xemacs.info, Node: Recover, Prev: Auto Save Control, Up: Auto Save
- 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.
+Recovering Data from Auto-Saves
+-------------------------------
- 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.
+ If you want to use the contents of an auto-save file to recover from
+a loss of data, use the command `M-x recover-file <RET> FILE <RET>'.
+Emacs visits FILE and then (after your confirmation) restores the
+contents from the auto-save file `#FILE#'. You can then save the file
+with `C-x C-s' to put the recovered text into FILE itself. For
+example, to recover file `foo.c' from its auto-save file `#foo.c#', do:
- 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.
+ M-x recover-file <RET> foo.c <RET>
+ C-x C-s
- 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.
+ Before asking for confirmation, `M-x recover-file' displays a
+directory listing describing the specified file and the auto-save file,
+so you can compare their sizes and dates. If the auto-save file is
+older, `M-x recover-file' does not offer to read it.
- Note that you can also use `C-x C-f' and any other command for
-visiting a file to switch buffers. *Note Visiting::.
+ Auto-saving is disabled by `M-x recover-file' because using this
+command implies that the auto-save file contains valuable data from a
+past session. If you save the data in the visited file and then go on
+to make new changes, turn auto-saving back on with `M-x auto-save-mode'.
\1f
-File: xemacs.info, Node: List Buffers, Next: Misc Buffer, Prev: Select Buffer, Up: Buffers
+File: xemacs.info, Node: Version Control, Next: ListDir, Prev: Auto Save, Up: Files
-Listing Existing Buffers
-========================
+Version Control
+===============
-`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.
+ "Version control systems" are packages that can record multiple
+versions of a source file, usually storing the unchanged parts of the
+file just once. Version control systems also record history information
+such as the creation time of each version, who created it, and a
+description of what was changed in that version.
-\1f
-File: xemacs.info, Node: Misc Buffer, Next: Kill Buffer, Prev: List Buffers, Up: Buffers
+ The GNU project recommends the version control system known as RCS,
+which is free software and available from the Free Software Foundation.
+Emacs supports use of either RCS or SCCS (a proprietary, but widely
+used, version control system that is not quite as powerful as RCS)
+through a facility called VC. The same Emacs commands work with either
+RCS or SCCS, so you hardly have to know which one of them you are using.
-Miscellaneous Buffer Operations
-===============================
+* Menu:
-`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::.
+* Concepts of VC:: Basic version control information;
+ checking files in and out.
+* Editing with VC:: Commands for editing a file maintained
+ with version control.
+* Variables for Check-in/out:: Variables that affect the commands used
+ to check files in or out.
+* Log Entries:: Logging your changes.
+* Change Logs and VC:: Generating a change log file from log
+ entries.
+* Old Versions:: Examining and comparing old versions.
+* VC Status:: Commands to view the VC status of files and
+ look at log entries.
+* Renaming and VC:: A command to rename both the source and
+ master file correctly.
+* Snapshots:: How to make and use snapshots, a set of
+ file versions that can be treated as a unit.
+* Version Headers:: Inserting version control headers into
+ working files.
\1f
-File: xemacs.info, Node: Kill Buffer, Next: Several Buffers, Prev: Misc Buffer, Up: Buffers
+File: xemacs.info, Node: Concepts of VC, Next: Editing with VC, Prev: Version Control, Up: Version Control
-Killing Buffers
-===============
+Concepts of Version Control
+---------------------------
+
+ When a file is under version control, we also say that it is
+"registered" in the version control system. Each registered file has a
+corresponding "master file" which represents the file's present state
+plus its change history, so that you can reconstruct from it either the
+current version or any specified earlier version. Usually the master
+file also records a "log entry" for each version describing what was
+changed in that version.
- 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.
+ The file that is maintained under version control is sometimes called
+the "work file" corresponding to its master file.
-`C-x k'
- Kill a buffer, specified by name (`kill-buffer').
+ To examine a file, you "check it out". This extracts a version of
+the source file (typically, the most recent) from the master file. If
+you want to edit the file, you must check it out "locked". Only one
+user can do this at a time for any given source file. (This kind of
+locking is completely unrelated to the locking that Emacs uses to
+detect simultaneous editing of a file.)
-`M-x kill-some-buffers'
- Offer to kill each buffer, one by one.
+ When you are done with your editing, you must "check in" the new
+version. This records the new version in the master file, and unlocks
+the source file so that other people can lock it and thus modify it.
- `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.
+ Checkin and checkout are the basic operations of version control.
+You can do both of them with a single Emacs command: `C-x C-q'
+(`vc-toggle-read-only').
- 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'.
+ A "snapshot" is a coherent collection of versions of the various
+files that make up a program. *Note Snapshots::.
\1f
-File: xemacs.info, Node: Several Buffers, Prev: Kill Buffer, Up: Buffers
+File: xemacs.info, Node: Editing with VC, Next: Variables for Check-in/out, Prev: Concepts of VC, Up: Version Control
-Operating on Several Buffers
-============================
+Editing with Version Control
+----------------------------
- 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.
+ When you visit a file that is maintained using version control, the
+mode line displays `RCS' or `SCCS' to inform you that version control
+is in use, and also (in case you care) which low-level system the file
+is actually stored in. Normally, such a source file is read-only, and
+the mode line indicates this with `%%'. With RCS, the mode line also
+indicates the number of the head version, which is normally also the
+version you are looking at.
-`M-x buffer-menu'
- Begin editing a buffer listing all Emacs buffers.
+ These are the commands for editing a file maintained with version
+control:
- 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:
+`C-x C-q'
+ Check the visited file in or out.
+
+`C-x v u'
+ Revert the buffer and the file to the last checked in version.
+
+`C-x v c'
+ Remove the last-entered change from the master for the visited
+ file. This undoes your last check-in.
+
+`C-x v i'
+ Register the visited file in version control.
+
+(`C-x v' is the prefix key for version control commands; all of these
+commands except for `C-x C-q' start with `C-x v'.)
+
+ When you want to modify a file maintained with version control, type
+`C-x C-q' (`vc-toggle-read-only'). This "checks out" the file, and
+tells RCS or SCCS to lock the file. This means making the file
+writable for you (but not for anyone else).
+
+ When you are finished editing the file, type `C-x C-q' again. When
+used on a file that is checked out, this command checks the file in.
+But check-in does not start immediately; first, you must enter the "log
+entry"--a description of the changes in the new version. `C-x C-q'
+pops up a buffer for you to enter this in. When you are finished
+typing in the log entry, type `C-c C-c' to terminate it; this is when
+actual check-in takes place.
+
+ Once you have checked in your changes, the file is unlocked, so that
+other users can lock it and modify it.
+
+ Emacs does not save backup files for source files that are maintained
+with version control. If you want to make backup files despite version
+control, set the variable `vc-make-backup-files' to a non-`nil' value.
+
+ Normally the work file exists all the time, whether it is locked or
+not. If you set `vc-keep-workfiles' to `nil', then checking in a new
+version with `C-x C-q' deletes the work file; but any attempt to visit
+the file with Emacs creates it again.
+
+ It is not impossible to lock a file that someone else has locked. If
+you try to check out a file that is locked, `C-x C-q' asks you whether
+you want to "steal the lock." If you say yes, the file becomes locked
+by you, but a message is sent to the person who had formerly locked the
+file, to inform him of what has happened. The mode line indicates that
+a file is locked by someone else by displaying the login name of that
+person, before the version number.
+
+ If you want to discard your current set of changes and revert to the
+last version checked in, use `C-x v u' (`vc-revert-buffer'). This
+cancels your last check-out, leaving the file unlocked. If you want to
+make a different set of changes, you must first check the file out
+again. `C-x v u' requires confirmation, unless it sees that you
+haven't made any changes since the last checked-in version.
+
+ `C-x v u' is also the command to use if you lock a file and then
+don't actually change it.
+
+ You can cancel a change after checking it in, with `C-x v c'
+(`vc-cancel-version'). This command discards all record of the most
+recent checked in version, so be careful about using it. It requires
+confirmation with `yes'. By default, `C-x v c' reverts your workfile
+and buffer to the previous version (the one that precedes the version
+that is deleted), but you can prevent the reversion by giving the
+command a prefix argument. Then the buffer does not change.
+
+ This command with a prefix argument is useful when you have checked
+in a change and then discover a trivial error in it; you can cancel the
+erroneous check-in, fix the error, and repeat the check-in.
+
+ Be careful when invoking `C-x v c', as it is easy to throw away a
+lot of work with it. To help you be careful, this command always
+requires confirmation with `yes'.
+
+ You can register the visited file for version control using
+`C-x v i' (`vc-register'). If the variable `vc-default-back-end' is
+non-`nil', it specifies which version control system to use; otherwise,
+this uses RCS if it is installed on your system and SCCS if not. After
+`C-x v i', the file is unlocked and read-only. Type `C-x C-q' if you
+wish to edit it.
+
+ By default, the initial version number is 1.1. If you want to use a
+different number, give `C-x v i' a prefix argument; then it reads the
+initial version number using the minibuffer.
+
+ If `vc-initial-comment' is non-`nil', `C-x v i' reads an initial
+comment (much like a log entry) to describe the purpose of this source
+file.
+
+ To specify the version number for a subsequent checkin, use the
+command `C-u C-x v v'. `C-x v v' (`vc-next-action') is the command
+that `C-x C-q' uses to do the "real work" when the visited file uses
+version control. When used for checkin, and given a prefix argument,
+it reads the version number with the minibuffer.
-`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.
+\1f
+File: xemacs.info, Node: Variables for Check-in/out, Next: Log Entries, Prev: Editing with VC, Up: Version Control
+
+Variables Affecting Check-in and Check-out
+------------------------------------------
+
+ If `vc-suppress-confirm' is non-`nil', then `C-x C-q' and `C-x v i'
+can save the current buffer without asking, and `C-x v u' also operates
+without asking for confirmation. (This variable does not affect `C-x v
+c'; that is so drastic that it should always ask for confirmation.)
+
+ VC mode does much of its work by running the shell commands for RCS
+and SCCS. If `vc-command-messages' is non-`nil', VC displays messages
+to indicate which shell commands it runs, and additional messages when
+the commands finish.
+
+ Normally, VC assumes that it can deduce the locked/unlocked state of
+files by looking at the file permissions of the work file; this is
+fast. However, if the `RCS' or `SCCS' subdirectory is actually a
+symbolic link, then VC does not trust the file permissions to reflect
+this status.
+
+ You can specify the criterion for whether to trust the file
+permissions by setting the variable `vc-mistrust-permissions'. Its
+value may be `t' (always mistrust the file permissions and check the
+master file), `nil' (always trust the file permissions), or a function
+of one argument which makes the decision. The argument is the directory
+name of the `RCS' or `SCCS' subdirectory. A non-`nil' value from the
+function says to mistrust the file permissions.
+
+ If you find that the file permissions of work files are changed
+erroneously, set `vc-mistrust-permissions' to `t'. Then VC always
+checks the master file to determine the file's status.
+
+ You can specify additional directories to search for version control
+programs by setting the variable `vc-path'. These directories are
+searched before the usual search path. The proper result usually
+happens automatically.
-`k'
- Synonym for `d'.
+\1f
+File: xemacs.info, Node: Log Entries, Next: Change Logs and VC, Prev: Variables for Check-in/out, Up: Version Control
-`C-d'
- Like `d' but move up afterwards instead of down.
+Log Entries
+-----------
-`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.
+ When you're editing an initial comment or log entry for inclusion in
+a master file, finish your entry by typing `C-c C-c'.
-`~'
- Mark buffer "unmodified". The command `~' does this immediately
- when typed.
+`C-c C-c'
+ Finish the comment edit normally (`vc-finish-logentry'). This
+ finishes check-in.
-`x'
- Perform previously requested deletions and saves.
+ To abort check-in, just don't type `C-c C-c' in that buffer. You
+can switch buffers and do other editing. As long as you don't try to
+check in another file, the entry you were editing remains in its
+buffer, and you can go back to that buffer at any time to complete the
+check-in.
-`u'
- Remove any request made for the current line, and move down.
+ If you change several source files for the same reason, it is often
+convenient to specify the same log entry for many of the files. To do
+this, use the history of previous log entries. The commands `M-n',
+`M-p', `M-s' and `M-r' for doing this work just like the minibuffer
+history commands (except that these versions are used outside the
+minibuffer).
-`<DEL>'
- Move to previous line and remove any request made for that line.
+ Each time you check in a file, the log entry buffer is put into VC
+Log mode, which involves running two hooks: `text-mode-hook' and
+`vc-log-mode-hook'.
- 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.
+\1f
+File: xemacs.info, Node: Change Logs and VC, Next: Old Versions, Prev: Log Entries, Up: Version Control
+
+Change Logs and VC
+------------------
+
+ If you use RCS for a program and also maintain a change log file for
+it (*note Change Log::), you can generate change log entries
+automatically from the version control log entries:
+
+`C-x v a'
+ Visit the current directory's change log file and create new
+ entries for versions checked in since the most recent entry in the
+ change log file (`vc-update-change-log').
+
+ This command works with RCS only; it does not work with SCCS.
+
+ For example, suppose the first line of `ChangeLog' is dated 10 April
+1992, and that the only check-in since then was by Nathaniel Bowditch
+to `rcs2log' on 8 May 1992 with log text `Ignore log messages that
+start with `#'.'. Then `C-x v a' visits `ChangeLog' and inserts text
+like this:
+
+ Fri May 8 21:45:00 1992 Nathaniel Bowditch (nat@apn.org)
+
+ * rcs2log: Ignore log messages that start with `#'.
+
+You can then edit the new change log entry further as you wish.
+
+ Normally, the log entry for file `foo' is displayed as `* foo: TEXT
+OF LOG ENTRY'. The `:' after `foo' is omitted if the text of the log
+entry starts with `(FUNCTIONNAME): '. For example, if the log entry
+for `vc.el' is `(vc-do-command): Check call-process status.', then the
+text in `ChangeLog' looks like this:
+
+ Wed May 6 10:53:00 1992 Nathaniel Bowditch (nat@apn.org)
+
+ * vc.el (vc-do-command): Check call-process status.
+
+ When `C-x v a' adds several change log entries at once, it groups
+related log entries together if they all are checked in by the same
+author at nearly the same time. If the log entries for several such
+files all have the same text, it coalesces them into a single entry.
+For example, suppose the most recent checkins have the following log
+entries:
+
+For `vc.texinfo':
+ Fix expansion typos.
+For `vc.el':
+ Don't call expand-file-name.
+For `vc-hooks.el':
+ Don't call expand-file-name.
+
+ They appear like this in `ChangeLog':
+
+ Wed Apr 1 08:57:59 1992 Nathaniel Bowditch (nat@apn.org)
+
+ * vc.texinfo: Fix expansion typos.
+
+ * vc.el, vc-hooks.el: Don't call expand-file-name.
+
+ Normally, `C-x v a' separates log entries by a blank line, but you
+can mark several related log entries to be clumped together (without an
+intervening blank line) by starting the text of each related log entry
+with a label of the form `{CLUMPNAME} '. The label itself is not
+copied to `ChangeLog'. For example, suppose the log entries are:
+
+For `vc.texinfo':
+ {expand} Fix expansion typos.
+For `vc.el':
+ {expand} Don't call expand-file-name.
+For `vc-hooks.el':
+ {expand} Don't call expand-file-name.
+
+Then the text in `ChangeLog' looks like this:
+
+ Wed Apr 1 08:57:59 1992 Nathaniel Bowditch (nat@apn.org)
+
+ * vc.texinfo: Fix expansion typos.
+ * vc.el, vc-hooks.el: Don't call expand-file-name.
+
+ A log entry whose text begins with `#' is not copied to `ChangeLog'.
+For example, if you merely fix some misspellings in comments, you can
+log the change with an entry beginning with `#' to avoid putting such
+trivia into `ChangeLog'.
- 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.
+\1f
+File: xemacs.info, Node: Old Versions, Next: VC Status, Prev: Change Logs and VC, Up: Version Control
-`1'
- Select the buffer in a full-frame window. This command takes
- effect immediately.
+Examining And Comparing Old Versions
+------------------------------------
-`2'
- Immediately set up two windows, with this buffer in one and the
- buffer selected before `*Buffer List*' in the other.
+`C-x v ~ VERSION <RET>'
+ Examine version VERSION of the visited file, in a buffer of its
+ own (`vc-version-other-window').
-`f'
- Immediately select the buffer in place of the `*Buffer List*'
- buffer.
+`C-x v ='
+ Compare the current buffer contents with the latest checked-in
+ version of the file.
-`o'
- Immediately select the buffer in another window as if by `C-x 4 b',
- leaving `*Buffer List*' visible.
+`C-u C-x v = FILE <RET> OLDVERS <RET> NEWVERS <RET>'
+ Compare the specified two versions of FILE.
-`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.
+ You can examine any version of a file by first visiting it, and then
+using `C-x v ~ VERSION <RET>' (`vc-version-other-window'). This puts
+the text of version VERSION in a file named `FILENAME.~VERSION~', then
+visits it in a separate window.
-\1f
-File: xemacs.info, Node: Windows, Next: Mule, Prev: Buffers, Up: Top
+ To compare two versions of a file, use the command `C-x v ='
+(`vc-diff').
-Multiple Windows
-****************
+ Plain `C-x v =' compares the current buffer contents (saving them in
+the file if necessary) with the last checked-in version of the file.
+With a prefix argument, `C-x v =' reads a file name and two version
+numbers, then compares those versions of the specified file.
- 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.
+ If you supply a directory name instead of the name of a work file,
+this command compares the two specified versions of all registered files
+in that directory and its subdirectories. You can also specify a
+snapshot name (*note Snapshots::) instead of one or both version
+numbers.
-* Menu:
+ You can specify a checked-in version by its number; you can specify
+the most recent checked-in version with an empty version number.
-* 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.
+ This command works by running the `vcdiff' utility, getting the
+options from the variable `diff-switches'. It displays the output in a
+special buffer in another window. Unlike the `M-x diff' command, `C-x
+v =' does not try to find the changes in the old and new versions.
+This is because one or both versions normally do not exist as files.
+They exist only in the records of the master file. *Note Comparing
+Files::, for more information about `M-x diff'.
\1f
-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.
+File: xemacs.info, Node: VC Status, Next: Renaming and VC, Prev: Old Versions, Up: Version Control
+
+VC Status Commands
+------------------
+
+ To view the detailed version control status and history of a file,
+type `C-x v l' (`vc-print-log'). It displays the history of changes to
+the current file, including the text of the log entries. The output
+appears in a separate window.
+
+ When you are working on a large program, it's often useful to find
+all the files that are currently locked, or all the files maintained in
+version control at all. You can use `C-x v d' (`vc-directory') to show
+all the locked files in or beneath the current directory. This
+includes all files that are locked by any user. `C-u C-x v d' lists
+all files in or beneath the current directory that are maintained with
+version control.
+
+ The list of files is displayed as a buffer that uses an augmented
+Dired mode. The names of the users locking various files are shown (in
+parentheses) in place of the owner and group. All the normal Dired
+commands work in this buffer. Most interactive VC commands work also,
+and apply to the file name on the current line.
+
+ The `C-x v v' command (`vc-next-action'), when used in the augmented
+Dired buffer, operates on all the marked files (or the file on the
+current line). If it operates on more than one file, it handles each
+file according to its current state; thus, it may check out one file
+and check in another (because it is already checked out). If it has to
+check in any files, it reads a single log entry, then uses that text
+for all the files being checked in. This can be convenient for
+registering or checking in several files at once, as part of the same
+change.
\1f
-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').
+File: xemacs.info, Node: Renaming and VC, Next: Snapshots, Prev: VC Status, Up: Version Control
+
+Renaming VC Work Files and Master Files
+---------------------------------------
+
+ When you rename a registered file, you must also rename its master
+file correspondingly to get proper results. Use `vc-rename-file' to
+rename the source file as you specify, and rename its master file
+accordingly. It also updates any snapshots (*note Snapshots::) that
+mention the file, so that they use the new name; despite this, the
+snapshot thus modified may not completely work (*note Snapshot
+Caveats::).
+
+ You cannot use `vc-rename-file' on a file that is locked by someone
+else.
\1f
-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.
+File: xemacs.info, Node: Snapshots, Next: Version Headers, Prev: Renaming and VC, Up: Version Control
- 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.
+Snapshots
+---------
- A prefix argument IGNORE-WHITESPACE means ignore changes in
-whitespace. The variable `compare-windows-whitespace' controls how
-whitespace is skipped.
+ A "snapshot" is a named set of file versions (one for each
+registered file) that you can treat as a unit. One important kind of
+snapshot is a "release", a (theoretically) stable version of the system
+that is ready for distribution to users.
- If `compare-ignore-case' is non-`nil', changes in case are also
-ignored.
+* Menu:
+
+* Making Snapshots:: The snapshot facilities.
+* Snapshot Caveats:: Things to be careful of when using snapshots.
\1f
-File: xemacs.info, Node: Pop Up Window, Next: Change Window, Prev: Other Window, Up: Windows
+File: xemacs.info, Node: Making Snapshots, Next: Snapshot Caveats, Prev: Snapshots, Up: Snapshots
-Displaying in Another Window
-============================
+Making and Using Snapshots
+..........................
- `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.
+ There are two basic commands for snapshots; one makes a snapshot
+with a given name, the other retrieves a named snapshot.
-`C-x 4 b BUFNAME <RET>'
- Select buffer BUFNAME in another window. This runs
- `switch-to-buffer-other-window'.
+`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 4 f FILENAME <RET>'
- Visit file FILENAME and select its buffer in another window. This
- runs `find-file-other-window'. *Note Visiting::.
+`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').
-`C-x 4 d DIRECTORY <RET>'
- Select a Dired buffer for directory DIRECTORY in another window.
- This runs `dired-other-window'. *Note Dired::.
+ 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.
-`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::.).
+ 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.
-`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::.).
+ 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.
- 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: 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: 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.
+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: Mule, Next: Major Modes, Prev: Windows, Up: Top
+File: xemacs.info, Node: ListDir, Next: Comparing Files, Prev: Version Control, Up: Files
-World Scripts Support
-*********************
+Listing a File Directory
+========================
- 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").
+ 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).
-* Menu:
+`C-x C-d DIR-OR-PATTERN'
+ Print a brief directory listing (`list-directory').
-* 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.
+`C-u C-x C-d DIR-OR-PATTERN'
+ Print a verbose directory listing.
-\1f
-File: xemacs.info, Node: Mule Intro, Next: Language Environments, Prev: Mule, Up: Mule
+ 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,
-Introduction to world scripts
-=============================
+ C-x C-d /u2/emacs/etc <RET>
- 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).
+lists all the files in directory `/u2/emacs/etc'. An example of
+specifying a file name pattern is:
- 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.
+ C-x C-d /u2/emacs/src/*.c <RET>
- 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.
+ 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').
- The prefix key `C-x <RET>' is used for commands that pertain to
-world scripts, coding systems, and input methods.
+ 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).
-\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.
+ 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 ``^''.
-\1f
-File: xemacs.info, Node: Input Methods, Next: Select Input Method, Prev: Language Environments, Up: Mule
-
-Input Methods
-=============
-
- An "input method" is a kind of character conversion designed
-specifically for interactive input. In XEmacs, typically each language
-has its own input method; sometimes several languages which use the same
-characters can share one input method. A few languages support several
-input methods.
-
- The simplest kind of input method works by mapping ASCII letters into
-another alphabet. This is how the Greek and Russian input methods work.
-
- A more powerful technique is composition: converting sequences of
-characters into one letter. Many European input methods use composition
-to produce a single non-ASCII letter from a sequence that consists of a
-letter followed by accent characters. For example, some methods convert
-the sequence `'a' into a single accented letter.
-
- The input methods for syllabic scripts typically use mapping followed
-by composition. The input methods for Thai and Korean work this way.
-First, letters are mapped into symbols for particular sounds or tone
-marks; then, sequences of these which make up a whole syllable are
-mapped into one syllable sign.
-
- Chinese and Japanese require more complex methods. In Chinese input
-methods, first you enter the phonetic spelling of a Chinese word (in
-input method `chinese-py', among others), or a sequence of portions of
-the character (input methods `chinese-4corner' and `chinese-sw', and
-others). Since one phonetic spelling typically corresponds to many
-different Chinese characters, you must select one of the alternatives
-using special XEmacs commands. Keys such as `C-f', `C-b', `C-n',
-`C-p', and digits have special definitions in this situation, used for
-selecting among the alternatives. <TAB> displays a buffer showing all
-the possibilities.
-
- In Japanese input methods, first you input a whole word using
-phonetic spelling; then, after the word is in the buffer, XEmacs
-converts it into one or more characters using a large dictionary. One
-phonetic spelling corresponds to many differently written Japanese
-words, so you must select one of them; use `C-n' and `C-p' to cycle
-through the alternatives.
-
- Sometimes it is useful to cut off input method processing so that the
-characters you have just entered will not combine with subsequent
-characters. For example, in input method `latin-1-postfix', the
-sequence `e '' combines to form an `e' with an accent. What if you
-want to enter them as separate characters?
-
- One way is to type the accent twice; that is a special feature for
-entering the separate letter and accent. For example, `e ' '' gives
-you the two characters `e''. Another way is to type another letter
-after the `e'--something that won't combine with that--and immediately
-delete it. For example, you could type `e e <DEL> '' to get separate
-`e' and `''.
-
- Another method, more general but not quite as easy to type, is to use
-`C-\ C-\' between two characters to stop them from combining. This is
-the command `C-\' (`toggle-input-method') used twice. *Note Select
-Input Method::.
-
- `C-\ C-\' is especially useful inside an incremental search, because
-stops waiting for more characters to combine, and starts searching for
-what you have already entered.
-
- The variables `input-method-highlight-flag' and
-`input-method-verbose-flag' control how input methods explain what is
-happening. If `input-method-highlight-flag' is non-`nil', the partial
-sequence is highlighted in the buffer. If `input-method-verbose-flag'
-is non-`nil', the list of possible characters to type next is displayed
-in the echo area (but not when you are in the minibuffer).
+ 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.
\1f
-File: xemacs.info, Node: Select Input Method, Next: Coding Systems, Prev: Input Methods, Up: Mule
+File: xemacs.info, Node: Comparing Files, Next: Dired, Prev: ListDir, Up: Files
-Selecting an Input Method
-=========================
+Comparing Files
+===============
-`C-\'
- Enable or disable use of the selected input method.
+ 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.
-`C-x <RET> C-\ METHOD <RET>'
- Select a new input method for the current buffer.
+ 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::.
-`C-h I METHOD <RET>'
-`C-h C-\ METHOD <RET>'
- Describe the input method METHOD (`describe-input-method'). By
- default, it describes the current input method (if any).
+ 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.
-`M-x list-input-methods'
- Display a list of all the supported input methods.
+ 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::.
- To choose an input method for the current buffer, use `C-x <RET>
-C-\' (`select-input-method'). This command reads the input method name
-with the minibuffer; the name normally starts with the language
-environment that it is meant to be used with. The variable
-`current-input-method' records which input method is selected.
+ 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.
- Input methods use various sequences of ASCII characters to stand for
-non-ASCII characters. Sometimes it is useful to turn off the input
-method temporarily. To do this, type `C-\' (`toggle-input-method').
-To reenable the input method, type `C-\' again.
+\1f
+File: xemacs.info, Node: Dired, Next: Misc File Ops, Prev: Comparing Files, Up: Files
- If you type `C-\' and you have not yet selected an input method, it
-prompts for you to specify one. This has the same effect as using `C-x
-<RET> C-\' to specify an input method.
+Dired, the Directory Editor
+===========================
- Selecting a language environment specifies a default input method for
-use in various buffers. When you have a default input method, you can
-select it in the current buffer by typing `C-\'. The variable
-`default-input-method' specifies the default input method (`nil' means
-there is none).
+ 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.
- Some input methods for alphabetic scripts work by (in effect)
-remapping the keyboard to emulate various keyboard layouts commonly used
-for those scripts. How to do this remapping properly depends on your
-actual keyboard layout. To specify which layout your keyboard has, use
-the command `M-x quail-set-keyboard-layout'.
+* Menu:
- To display a list of all the supported input methods, type `M-x
-list-input-methods'. The list gives information about each input
-method, including the string that stands for it in the mode line.
+* 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.
\1f
-File: xemacs.info, Node: Coding Systems, Next: Recognize Coding, Prev: Select Input Method, Up: Mule
-
-Coding Systems
-==============
-
- Users of various languages have established many more-or-less
-standard coding systems for representing them. XEmacs does not use
-these coding systems internally; instead, it converts from various
-coding systems to its own system when reading data, and converts the
-internal coding system to other coding systems when writing data.
-Conversion is possible in reading or writing files, in sending or
-receiving from the terminal, and in exchanging data with subprocesses.
-
- XEmacs assigns a name to each coding system. Most coding systems are
-used for one language, and the name of the coding system starts with the
-language name. Some coding systems are used for several languages;
-their names usually start with `iso'. There are also special coding
-systems `binary' and `no-conversion' which do not convert printing
-characters at all.
-
- In addition to converting various representations of non-ASCII
-characters, a coding system can perform end-of-line conversion. XEmacs
-handles three different conventions for how to separate lines in a file:
-newline, carriage-return linefeed, and just carriage-return.
-
-`C-h C CODING <RET>'
- Describe coding system CODING.
-
-`C-h C <RET>'
- Describe the coding systems currently in use.
-
-`M-x list-coding-systems'
- Display a list of all the supported coding systems.
-
- The command `C-h C' (`describe-coding-system') displays information
-about particular coding systems. You can specify a coding system name
-as argument; alternatively, with an empty argument, it describes the
-coding systems currently selected for various purposes, both in the
-current buffer and as the defaults, and the priority list for
-recognizing coding systems (*note Recognize Coding::.).
-
- To display a list of all the supported coding systems, type `M-x
-list-coding-systems'. The list gives information about each coding
-system, including the letter that stands for it in the mode line (*note
-Mode Line::.).
-
- Each of the coding systems that appear in this list--except for
-`binary', which means no conversion of any kind--specifies how and
-whether to convert printing characters, but leaves the choice of
-end-of-line conversion to be decided based on the contents of each file.
-For example, if the file appears to use carriage-return linefeed between
-lines, that end-of-line conversion will be used.
-
- Each of the listed coding systems has three variants which specify
-exactly what to do for end-of-line conversion:
-
-`...-unix'
- Don't do any end-of-line conversion; assume the file uses newline
- to separate lines. (This is the convention normally used on Unix
- and GNU systems.)
-
-`...-dos'
- Assume the file uses carriage-return linefeed to separate lines,
- and do the appropriate conversion. (This is the convention
- normally used on Microsoft systems.)
-
-`...-mac'
- Assume the file uses carriage-return to separate lines, and do the
- appropriate conversion. (This is the convention normally used on
- the Macintosh system.)
-
- These variant coding systems are omitted from the
-`list-coding-systems' display for brevity, since they are entirely
-predictable. For example, the coding system `iso-8859-1' has variants
-`iso-8859-1-unix', `iso-8859-1-dos' and `iso-8859-1-mac'.
-
- In contrast, the coding system `binary' specifies no character code
-conversion at all--none for non-Latin-1 byte values and none for end of
-line. This is useful for reading or writing binary files, tar files,
-and other files that must be examined verbatim.
-
- The easiest way to edit a file with no conversion of any kind is with
-the `M-x find-file-literally' command. This uses `binary', and also
-suppresses other XEmacs features that might convert the file contents
-before you see them. *Note Visiting::.
-
- The coding system `no-conversion' means that the file contains
-non-Latin-1 characters stored with the internal XEmacs encoding. It
-handles end-of-line conversion based on the data encountered, and has
-the usual three variants to specify the kind of end-of-line conversion.
+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: Recognize Coding, Next: Specify Coding, Prev: Coding Systems, Up: Mule
-
-Recognizing Coding Systems
-==========================
-
- Most of the time, XEmacs can recognize which coding system to use for
-any given file-once you have specified your preferences.
-
- Some coding systems can be recognized or distinguished by which byte
-sequences appear in the data. However, there are coding systems that
-cannot be distinguished, not even potentially. For example, there is no
-way to distinguish between Latin-1 and Latin-2; they use the same byte
-values with different meanings.
-
- XEmacs handles this situation by means of a priority list of coding
-systems. Whenever XEmacs reads a file, if you do not specify the coding
-system to use, XEmacs checks the data against each coding system,
-starting with the first in priority and working down the list, until it
-finds a coding system that fits the data. Then it converts the file
-contents assuming that they are represented in this coding system.
-
- The priority list of coding systems depends on the selected language
-environment (*note Language Environments::.). For example, if you use
-French, you probably want XEmacs to prefer Latin-1 to Latin-2; if you
-use Czech, you probably want Latin-2 to be preferred. This is one of
-the reasons to specify a language environment.
-
- However, you can alter the priority list in detail with the command
-`M-x prefer-coding-system'. This command reads the name of a coding
-system from the minibuffer, and adds it to the front of the priority
-list, so that it is preferred to all others. If you use this command
-several times, each use adds one element to the front of the priority
-list.
-
- Sometimes a file name indicates which coding system to use for the
-file. The variable `file-coding-system-alist' specifies this
-correspondence. There is a special function
-`modify-coding-system-alist' for adding elements to this list. For
-example, to read and write all `.txt' using the coding system
-`china-iso-8bit', you can execute this Lisp expression:
-
- (modify-coding-system-alist 'file "\\.txt\\'" 'china-iso-8bit)
-
-The first argument should be `file', the second argument should be a
-regular expression that determines which files this applies to, and the
-third argument says which coding system to use for these files.
-
- You can specify the coding system for a particular file using the
-`-*-...-*-' construct at the beginning of a file, or a local variables
-list at the end (*note File Variables::.). You do this by defining a
-value for the "variable" named `coding'. XEmacs does not really have a
-variable `coding'; instead of setting a variable, it uses the specified
-coding system for the file. For example, `-*-mode: C; coding:
-iso-8859-1;-*-' specifies use of the iso-8859-1 coding system, as well
-as C mode.
-
- Once XEmacs has chosen a coding system for a buffer, it stores that
-coding system in `buffer-file-coding-system' and uses that coding
-system, by default, for operations that write from this buffer into a
-file. This includes the commands `save-buffer' and `write-region'. If
-you want to write files from this buffer using a different coding
-system, you can specify a different coding system for the buffer using
-`set-buffer-file-coding-system' (*note Specify Coding::.).
+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.
projects / chise / xemacs-chise.git / blobdiff