1 GNU Emacs NEWS -- history of user-visible changes. 26-Mar-1986
3 Copyright (C) 1985-1986, 2006-2011 Free Software Foundation, Inc.
4 See the end of the file for license conditions.
7 This file is about changes in emacs versions 1 through 17.
25 * Sun3, Tahoe, Apollo, HP9000s300, Celerity, NCR Tower 32,
26 Sequent, Stride, Encore, Plexus and AT&T 7300 machines supported.
28 The Tahoe, Sun3, Sequent and Celerity use 4.2. In regard to the
29 Apollo, see the file APOLLO in this directory. NCR Tower32,
30 HP9000s300, Stride and Nu run forms of System V. System V rel 2 also
31 works on Vaxes now. See etc/MACHINES.
33 * System V Unix supported, including subprocesses.
35 It should be possible now to bring up Emacs on a machine running
36 mere unameliorated system V Unix with no major work; just possible bug
37 fixes. But you can expect to find a handful of those on any machine
38 that Emacs has not been run on before.
40 * Berkeley 4.1 Unix supported.
44 * Portable `alloca' provided.
46 Emacs can now run on machines that do not and cannot support the library
47 subroutine `alloca' in the canonical fashion, using an `alloca' emulation
52 Info now contains an Emacs manual, with essentially the same text
53 as in the printed manual.
55 The manual can now be printed with a standard TeX.
57 Nicely typeset and printed copies of the manual are available
58 from the Free Software Foundation.
60 * Backup file version numbers.
62 Emacs now supports version numbers in backup files.
64 The first time you save a particular file in one editing session,
65 the old file is copied or renamed to serve as a backup file.
66 In the past, the name for the backup file was made by appending `~'
67 to the end of the original file name.
69 Now the backup file name can instead be made by appending ".~NN~" to
70 the original file name, where NN stands for a numeric version. Each
71 time this is done, the new version number is one higher than the
72 highest previously used.
74 Thus, the active, current file does not have a version number.
75 Only the backups have them.
77 This feature is controlled by the variable `version-control'. If it
78 is `nil', as normally, then numbered backups are made only for files
79 that already have numbered backups. Backup names with just `~' are
80 used for files that have no numbered backups.
82 If `version-control' is `never', then the backup file's name is
83 made with just `~' in any case.
85 If `version-control' is not `nil' or `never', numbered backups are
88 To prevent unlimited consumption of disk space, Emacs can delete
89 old backup versions automatically. Generally Emacs keeps the first
90 few backups and the latest few backups, deleting any in between.
91 This happens every time a new backup is made. The two variables that
92 control the deletion are `kept-old-versions' and `kept-new-versions'.
93 Their values are, respectively, the number of oldest backups to keep
94 and the number of newest ones to keep, each time a new backup is made.
95 The value of `kept-new-versions' includes the backup just created.
96 By default, both values are 2.
98 If `trim-versions-without-asking' is non-`nil', the excess middle versions
99 are deleted without a murmur. If it is `nil', the default, then you
100 are asked whether the excess middle versions should really be deleted.
102 Dired has a new command `.' which marks for deletion all but the latest
103 and oldest few of every numeric series of backups. `kept-old-versions'
104 controls the number of oldest versions to keep, and `dired-kept-versions'
105 controls the number of latest versions to keep. A numeric argument to
106 the `.' command, if positive, specifies the number of latest versions
107 to keep, overriding `dired-kept-versions'. A negative argument specifies
108 the number of oldest versions to keep, using minus the argument to override
111 * Immediate conflict detection.
113 Emacs now locks the files it is modifying, so that if
114 you start to modify within Emacs a file that is being
115 modified in another Emacs, you get an immediate warning.
117 The warning gives you three choices:
118 1. Give up, and do not make any changes.
119 2. Make changes anyway at your own risk.
120 3. Make changes anyway, and record yourself as
121 the person locking the file (instead of whoever
122 was previously recorded.)
124 Just visiting a file does not lock it. It is locked
125 when you try to change the buffer that is visiting the file.
126 Saving the file unlocks it until you make another change.
128 Locking is done by writing a lock file in a special designated
129 directory. If such a directory is not provided and told to
130 Emacs as part of configuring it for your machine, the lock feature
135 This command is used to get a file back from an auto-save
136 (after a system crash, for example). It takes a file name
137 as argument and visits that file, but gets the data from the
138 file's last auto save rather than from the file itself.
142 This command resets the current buffer's major mode and local
143 variables to be as specified by the visit filename, the -*- line
144 and/or the Local Variables: block at the end of the buffer.
145 It is the same thing normally done when a file is first visited.
147 * Echo area messages disappear shortly if minibuffer is in use.
149 Any message in the echo area disappears after 2 seconds
150 if the minibuffer is active. This allows the minibuffer
151 to become visible again.
153 * C-z on System V runs a subshell.
155 On systems which do not allow programs to be suspended, the C-z command
156 forks a subshell that talks directly to the terminal, and then waits
157 for the subshell to exit. This gets almost the effect of suspending
158 in that you can run other programs and then return to Emacs. However,
159 you cannot log out from the subshell.
161 * C-c is always a prefix character.
163 Also, subcommands of C-c which are letters are always
164 reserved for the user. No standard Emacs major mode
167 * Picture mode C-c commands changed.
169 The old C-c k command is now C-c C-w.
170 The old C-c y command is now C-c C-x.
172 * Shell mode commands changed.
174 All the special commands of Shell mode are now moved onto
175 the C-c prefix. Most are not changed aside from that.
176 Thus, the old Shell mode C-c command (kill current job)
177 is now C-c C-c; the old C-z (suspend current job) is now C-c C-z,
180 The old C-x commands are now C-c commands. C-x C-k (kill output)
181 is now C-c C-o, and C-x C-v (show output) is now C-c C-r.
183 The old M-= (copy previous input) command is now C-c C-y.
185 * Shell mode recognizes aliases for `pushd', `popd' and `cd'.
187 Shell mode now uses the variable `shell-pushd-regexp' as a
188 regular expression to recognize any command name that is
189 equivalent to a `pushd' command. By default it is set up
190 to recognize just `pushd' itself. If you use aliases for
191 `pushd', change the regexp to recognize them as well.
193 There are also `shell-popd-regexp' to recognize commands
194 with the effect of a `popd', and `shell-cd-regexp' to recognize
195 commands with the effect of a `cd'.
197 * "Exit" command in certain modes now C-c C-c.
199 These include electric buffer menu mode, electric command history
200 mode, Info node edit mode, and Rmail edit mode. In all these
201 modes, the command to exit used to be just C-c.
203 * Outline mode changes.
205 Lines that are not heading lines are now called "body" lines.
206 The command `hide-text' is renamed to `hide-body'.
207 The key M-H is renamed to C-c C-h.
208 The key M-S is renamed to C-c C-s.
209 The key M-s is renamed to C-c C-i.
211 Changes of line visibility are no longer undoable. As a result,
212 they no longer use up undo memory and no longer interfere with
213 undoing earlier commands.
217 The s and q commands now both expunge deleted messages before saving;
218 use C-x C-s to save without expunging.
220 The u command now undeletes the current message if it is deleted;
221 otherwise, it backs up as far as necessary to reach a deleted message,
222 and undeletes that one. The u command in the summary behaves likewise,
223 but considers only messages listed in the summary. The M-u command
226 The o and C-o keys' meanings are interchanged.
227 o now outputs to an Rmail file, and C-o to a Unix mail file.
229 The F command (rmail-find) is renamed to M-s (rmail-search).
230 Various new commands and features exist; see the Emacs manual.
232 * Local bindings described first in describe-bindings.
234 * [...], {...} now balance in Fundamental mode.
236 * Nroff mode and TeX mode.
238 There are two new major modes for editing nroff input and TeX input.
239 See the Emacs manual for full information.
241 * New C indentation style variable `c-brace-imaginary-offset'.
243 The value of `c-brace-imaginary-offset', normally zero, controls the
244 indentation of a statement inside a brace-group where the open-brace
245 is not the first thing on a line. The value says where the open-brace
246 is imagined to be, relative to the first nonblank character on the line.
248 * Dired improvements.
250 Dired now normally keeps the cursor at the beginning of the file name,
251 not at the beginning of the line. The most used motion commands are
252 redefined in Dired to position the cursor this way.
254 `n' and `p' are now equivalent in dired to `C-n' and `C-p'.
256 If any files to be deleted cannot be deleted, their names are
257 printed in an error message.
259 If the `v' command is invoked on a file which is a directory,
260 dired is run on that directory.
262 * `visit-tag-table' renamed `visit-tags-table'.
264 This is so apropos of `tags' finds everything you need to
265 know about in connection with Tags.
267 * `mh-e' library uses C-c as prefix.
269 All the special commands of `mh-rmail' now are placed on a
270 C-c prefix rather than on the C-x prefix. This is for
271 consistency with other special modes with their own commands.
273 * M-$ or `spell-word' checks word before point.
275 It used to check the word after point.
277 * Quitting during autoloading no longer causes trouble.
279 Now, when a file is autoloaded, all function redefinitions
280 and `provide' calls are recorded and are undone if you quit
281 before the file is finished loading.
283 As a result, it no longer happens that some of the entry points
284 which are normally autoloading have been defined already, but the
285 entire file is not really present to support them.
287 * `else' can now be indented correctly in C mode.
289 TAB in C mode now knows which `if' statement an `else' matches
290 up with, and can indent the `else' correctly under the `if',
291 even if the `if' contained such things as another `if' statement,
292 or a `while' or `for' statement, with no braces around it.
294 * `batch-byte-compile'
296 Runs byte-compile-file on the files specified on the command line.
297 All the rest of the command line arguments are taken as files to
298 compile (or, if directories, to do byte-recompile-directory on).
299 Must be used only with -batch, and kills emacs on completion.
300 Each file will be processed even if an error occurred previously.
301 For example, invoke `emacs -batch -f batch-byte-compile *.el'.
305 `-batch' now implies `-q': no init file is loaded by Emacs when
306 `-batch' is used. Also, no `term/TERMTYPE.el' file is loaded. Auto
307 saving is not done except in buffers in which it is explicitly
308 requested. Also, many echo-area printouts describing what is going on
309 are inhibited in batch mode, so that the only output you get is the
310 output you program specifically.
312 One echo-area message that is not suppressed is the one that says
313 that a file is being loaded. That is because you can prevent this
314 message by passing `t' as the third argument to `load'.
316 * Display of search string in incremental search.
318 Now, when you type C-s or C-r to reuse the previous search
319 string, that search string is displayed immediately in the echo area.
321 Three dots are displayed after the search string while search
322 is actually going on.
326 The commands C-x ], C-x [, C-x /, C-x j and C-x o are now
327 available inside `view-buffer' and `view-file', with their
330 * Full-width windows preferred.
332 The ``other-window'' commands prefer other full width windows,
333 and will split only full width windows.
335 * M-x rename-file can copy if necessary.
337 When used between different file systems, since actual renaming does
338 not work, the old file will be copied and deleted.
340 * Within C-x ESC, you can pick the command to repeat.
342 While editing a previous command to be repeated, inside C-x ESC,
343 you can now use the commands M-p and M-n to pick an earlier or
344 later command to repeat. M-n picks the next earlier command
345 and M-p picks the next later one. The new command appears in
346 the minibuffer, and you can go ahead and edit it, and repeat it
347 when you exit the minibuffer.
349 Using M-n or M-p within C-x ESC is like having used a different
350 numeric argument when you ran C-x ESC in the first place.
352 The command you finally execute using C-x ESC is added to the
353 front of the command history, unless it is identical with the
354 first thing in the command history.
356 * Use C-c C-c to exit from editing within Info.
358 It used to be C-z for this. Somehow this use of C-z was
359 left out when all the others were moved. The intention is that
360 C-z should always suspend Emacs.
362 * Default arg to C-x < and C-x > now window width minus 2.
364 These commands, which scroll the current window horizontally
365 by a specified number of columns, now scroll a considerable
366 distance rather than a single column if used with no argument.
368 * Auto Save Files Deleted.
370 The default value of `delete-auto-save-files' is now `t', so that
371 when you save a file for real, its auto save file is deleted.
375 The N, P and J keys in Rnews are renamed to M-n, M-p and M-j.
376 These keys move among newsgroups.
378 The n and p keys for moving sequentially between news articles now
379 accept repeat count arguments, and the + and - keys, made redundant by
380 this change, are eliminated.
382 The s command for outputting the current article to a file
383 is renamed as o, to be compatible with Rmail.
387 If you have a ~/.mailrc file, Emacs searches it for mailing address
388 aliases, and these aliases are expanded when you send mail in Emacs.
390 Fcc fields can now be used in the headers in the *mail* buffer
391 to specify files in which copies of the message should be put.
392 The message is written into those files in Unix mail file format.
393 The message as sent does not contain any Fcc fields in its header.
394 You can use any number of Fcc fields, but only one file name in each one.
395 The variable `mail-archive-file-name', if non-`nil', can be a string
396 which is a file name; an Fcc to that file will be inserted in every
397 message when you begin to compose it.
399 A new command C-c q now exists in Mail mode. It fills the
400 paragraphs of an old message that had been inserted with C-c y.
402 When the *mail* buffer is put in Mail mode, text-mode-hook
403 is now run in addition to mail-mode-hook. text-mode-hook
406 The new variable `mail-header-separator' now specifies the string
407 to use on the line that goes between the headers and the message text.
408 By default it is still "--text follows this line--".
410 * Command history truncated automatically.
412 Just before each garbage collection, all but the last 30 elements
413 of the command history are discarded.
416 Incompatible Lisp Programming Changes in Emacs 17
418 * `"e' no longer supported.
420 This feature, which allowed Lisp functions to take arguments
421 that were not evaluated, has been eliminated, because it is
422 inescapably hard to make the compiler work properly with such
425 You should use macros instead. A simple way to change any
426 code that uses `"e' is to replace
428 (defun foo ("e x y z) ...
432 (defmacro foo (x y z)
433 (list 'foo-1 (list 'quote x) (list 'quote y) (list 'quote z)))
435 (defun foo-1 (x y z) ...
437 * Functions `region-to-string' and `region-around-match' removed.
439 These functions were made for compatibility with Gosling Emacs, but it
440 turns out to be undesirable to use them in GNU Emacs because they use
441 the mark. They have been eliminated from Emacs proper, but are
442 present in mlsupport.el for the sake of converted mocklisp programs.
444 If you were using `region-to-string', you should instead use
445 `buffer-substring'; then you can pass the bounds as arguments and
446 can avoid setting the mark.
448 If you were using `region-around-match', you can use instead
449 the two functions `match-beginning' and `match-end'. These give
450 you one bound at a time, as a numeric value, without changing
453 * Function `function-type' removed.
455 This just appeared not to be very useful. It can easily be written in
456 Lisp if you happen to want it. Just use `symbol-function' to get the
457 function definition of a symbol, and look at its data type or its car
460 * Variable `buffer-number' removed.
462 You can still use the function `buffer-number' to find out
463 a buffer's unique number (assigned in order of creation).
465 * Variable `executing-macro' renamed `executing-kbd-macro'.
467 This variable is the currently executing keyboard macro, as
468 a string, or `nil' when no keyboard macro is being executed.
470 * Loading term/$TERM.
472 The library term/$TERM (where $TERM get replaced by your terminal
473 type), which is done by Emacs automatically when it starts up, now
474 happens after the user's .emacs file is loaded.
476 In previous versions of Emacs, these files had names of the form
477 term-$TERM; thus, for example, term-vt100.el, but now they live
478 in a special subdirectory named term, and have names like
481 * `command-history' format changed.
483 The elements of this list are now Lisp expressions which can
484 be evaluated directly to repeat a command.
486 * Unused editing commands removed.
488 The functions `forward-to-word', `backward-to-word',
489 `upcase-char', `mark-beginning-of-buffer' and `mark-end-of-buffer'
490 have been removed. Their definitions can be found in file
491 lisp/unused.el if you need them.
494 Upward Compatible Lisp Programming Changes in Emacs 17
496 * You can now continue after errors and quits.
498 When the debugger is entered because of a C-g, due to
499 a non-`nil' value of `debug-on-quit', the `c' command in the debugger
500 resumes execution of the code that was running when the quit happened.
501 Use the `q' command to go ahead and quit.
503 The same applies to some kinds of errors, but not all. Errors
504 signaled with the Lisp function `signal' can be continued; the `c'
505 command causes `signal' to return. The `r' command causes `signal' to
506 return the value you specify. The `c' command is equivalent to `r'
507 with the value `nil'.
509 For a `wrong-type-argument' error, the value returned with the `r'
510 command is used in place of the invalid argument. If this new value
511 is not valid, another error occurs.
513 Errors signaled with the function `error' cannot be continued.
514 If you try to continue, the error just happens again.
516 * `dot' renamed `point'.
518 The word `dot' has been replaced with `point' in all
519 function and variable names, including:
521 point, point-min, point-max,
522 point-marker, point-min-marker, point-max-marker,
523 window-point, set-window-point,
524 point-to-register, register-to-point,
525 exchange-point-and-mark.
527 The old names are still supported, for now.
529 * `string-match' records position of end of match.
531 After a successful call to `string-match', `(match-end 0)' will
532 return the index in the string of the first character after the match.
533 Also, `match-begin' and `match-end' with nonzero arguments can be
534 used to find the indices of beginnings and ends of substrings matched
535 by subpatterns surrounded by parentheses.
537 * New function `insert-before-markers'.
539 This function is just like `insert' except in the handling of any
540 relocatable markers that are located at the point of insertion.
541 With `insert', such markers end up pointing before the inserted text.
542 With `insert-before-markers', they end up pointing after the inserted
545 * New function `copy-alist'.
547 This function takes one argument, a list, and makes a disjoint copy
548 of the alist structure. The list itself is copied, and each element
549 that is a cons cell is copied, but the cars and cdrs of elements
550 remain shared with the original argument.
552 This is what it takes to get two alists disjoint enough that changes
553 in one do not change the result of `assq' on the other.
555 * New function `copy-keymap'.
557 This function takes a keymap as argument and returns a new keymap
558 containing initially the same bindings. Rebindings in either one of
559 them will not alter the bindings in the other.
561 * New function `copy-syntax-table'.
563 This function takes a syntax table as argument and returns a new
564 syntax table containing initially the same syntax settings. Changes
565 in either one of them will not alter the other.
567 * Randomizing the random numbers.
569 `(random t)' causes the random number generator's seed to be set
570 based on the current time and Emacs's process id.
572 * Third argument to `modify-syntax-entry'.
574 The optional third argument to `modify-syntax-entry', if specified
575 should be a syntax table. The modification is made in that syntax table
576 rather than in the current syntax table.
578 * New function `run-hooks'.
580 This function takes any number of symbols as arguments.
581 It processes the symbols in order. For each symbol which
582 has a value (as a variable) that is non-nil, the value is
583 called as a function, with no arguments.
585 This is useful in major mode commands.
587 * Second arg to `switch-to-buffer'.
589 If this function is given a non-`nil' second argument, then the
590 selection being done is not recorded on the selection history.
591 The buffer's position in the history remains unchanged. This
592 feature is used by the view commands, so that the selection history
593 after exiting from viewing is the same as it was before.
595 * Second arg to `display-buffer' and `pop-to-buffer'.
597 These two functions both accept an optional second argument which
598 defaults to `nil'. If the argument is not `nil', it means that
599 another window (not the selected one) must be found or created to
600 display the specified buffer in, even if it is already shown in
603 This feature is used by `switch-to-buffer-other-window'.
605 * New variable `completion-ignore-case'.
607 If this variable is non-`nil', completion allows strings
608 in different cases to be considered matching. The global value
611 This variable exists for the sake of commands that are completing
612 an argument in which case is not significant. It is possible
613 to change the value globally, but you might not like the consequences
614 in the many situations (buffer names, command names, file names)
615 where case makes a difference.
617 * Major modes related to Text mode call text-mode-hook, then their own hooks.
619 For example, turning on Outline mode first calls the value of
620 `text-mode-hook' as a function, if it exists and is non-`nil',
621 and then does likewise for the variable `outline-mode-hook'.
623 * Defining new command line switches.
625 You can define a new command line switch in your .emacs file
626 by putting elements on the value of `command-switch-alist'.
627 Each element of this list should look like
628 (SWITCHSTRING . FUNCTION)
629 where SWITCHSTRING is a string containing the switch to be
630 defined, such as "-foo", and FUNCTION is a function to be called
631 if such an argument is found in the command line. FUNCTION
632 receives the command line argument, a string, as its argument.
634 To implement a switch that uses up one or more following arguments,
635 use the fact that the remaining command line arguments are kept
636 as a list in the variable `command-line-args'. FUNCTION can
637 examine this variable, and do
638 (setq command-line-args (cdr command-line-args)
639 to "use up" an argument.
641 * New variable `load-in-progress'.
643 This variable is non-`nil' when a file of Lisp code is being read
644 and executed by `load'.
646 * New variable `print-length'.
648 The value of this variable is normally `nil'. It may instead be
649 a number; in that case, when a list is printed by `prin1' or
650 `princ' only that many initial elements are printed; the rest are
653 * New variable `find-file-not-found-hook'.
655 If `find-file' or any of its variants is used on a nonexistent file,
656 the value of `find-file-not-found-hook' is called (if it is not `nil')
657 with no arguments, after creating an empty buffer. The file's name
658 can be found as the value of `buffer-file-name'.
660 * Processes without buffers.
662 In the function `start-process', you can now specify `nil' as
663 the process's buffer. You can also set a process's buffer to `nil'
664 using `set-process-buffer'.
666 The reason you might want to do this is to prevent the process
667 from being killed because any particular buffer is killed.
668 When a process has a buffer, killing that buffer kills the
671 When a process has no buffer, its output is lost unless it has a
672 filter, and no indication of its being stopped or killed is given
673 unless it has a sentinel.
675 * New function `user-variable-p'. `v' arg prompting changed.
677 This function takes a symbol as argument and returns `t' if
678 the symbol is defined as a user option variable. This means
679 that it has a `variable-documentation' property whose value is
680 a string starting with `*'.
682 Code `v' in an interactive arg reading string now accepts
683 user variables only, and completion is limited to the space of
686 The function `read-variable' also now accepts and completes
687 over user variables only.
689 * CBREAK mode input is the default in Unix 4.3 bsd.
691 In Berkeley 4.3 Unix, there are sufficient features for Emacs to
692 work fully correctly using CBREAK mode and not using SIGIO.
693 Therefore, this mode is the default when running under 4.3.
694 This mode corresponds to `nil' as the first argument to
695 `set-input-mode'. You can still select either mode by calling
698 * Information on memory usage.
700 The new variable `data-bytes-used' contains the number
701 of bytes of impure space allocated in Emacs.
702 `data-bytes-free' contains the number of additional bytes
703 Emacs could allocate. Note that space formerly allocated
704 and freed again still counts as `used', since it is still
705 in Emacs's address space.
707 * No limit on size of output from `format'.
709 The string output from `format' used to be truncated to
710 100 characters in length. Now it can have any length.
712 * New errors `void-variable' and `void-function' replace `void-symbol'.
714 This change makes it possible to have error messages that
715 clearly distinguish undefined variables from undefined functions.
716 It also allows `condition-case' to handle one case without the other.
718 * `replace-match' handling of `\'.
720 In `replace-match', when the replacement is not literal,
721 `\' in the replacement string is always treated as an
722 escape marker. The only two special `\' constructs
723 are `\&' and `\DIGIT', so `\' followed by anything other than
724 `&' or a digit has no effect. `\\' is necessary to include
725 a `\' in the replacement text.
727 This level of escaping is comparable with what goes on in
728 a regular expression. It is over and above the level of `\'
729 escaping that goes on when strings are read in Lisp syntax.
731 * New error `invalid-regexp'.
733 A regexp search signals this type of error if the argument does
734 not meet the rules for regexp syntax.
736 * `kill-emacs' with argument.
738 If the argument is a number, it is returned as the exit status code
739 of the Emacs process. If the argument is a string, its contents
740 are stuffed as pending terminal input, to be read by another program
743 * New fifth argument to `subst-char-in-region'.
745 This argument is optional and defaults to `nil'. If it is not `nil',
746 then the substitutions made by this function are not recorded
747 in the Undo mechanism.
749 This feature should be used with great care. It is now used
750 by Outline mode to make lines visible or invisible.
752 * ` *Backtrace*' buffer renamed to `*Backtrace*'.
754 As a result, you can now reselect this buffer easily if you switch to
755 another while in the debugger.
757 Exiting from the debugger kills the `*Backtrace*' buffer, so you will
758 not try to give commands in it when no longer really in the debugger.
760 * New function `switch-to-buffer-other-window'.
762 This is the new primitive to select a specified buffer (the
763 argument) in another window. It is not quite the same as
764 `pop-to-buffer', because it is guaranteed to create another
765 window (assuming there is room on the screen) so that it can
766 leave the current window's old buffer displayed as well.
768 All functions to select a buffer in another window should
769 do so by calling this new function.
771 * New variable `minibuffer-help-form'.
773 At entry to the minibuffer, the variable `help-form' is bound
774 to the value of `minibuffer-help-form'.
776 `help-form' is expected at all times to contain either `nil'
777 or an expression to be executed when C-h is typed (overriding
778 the definition of C-h as a command). `minibuffer-help-form'
779 can be used to provide a different default way of handling
780 C-h while in the minibuffer.
782 * New \{...} documentation construct.
784 It is now possible to set up the documentation string for
785 a major mode in such a way that it always describes the contents
786 of the major mode's keymap, as it has been customized.
787 To do this, include in the documentation string the characters `\{'
788 followed by the name of the variable containing the keymap,
789 terminated with `}'. (The `\' at the beginning probably needs to
790 be quoted with a second `\', to include it in the doc string.)
791 This construct is normally used on a line by itself, with no blank
792 lines before or after.
794 For example, the documentation string for the function `c-mode' contains
796 Paragraphs are separated by blank lines only.
797 Delete converts tabs to spaces as it moves back.
799 Variables controlling indentation style:
802 * New character syntax class "punctuation".
804 Punctuation characters behave like whitespace in word and
805 list parsing, but can be distinguished in regexps and in the
806 function `char-syntax'. Punctuation syntax is represented by
807 a period in `modify-syntax-entry'.
809 * `auto-mode-alist' no longer needs entries for backup-file names,
811 Backup suffixes of all kinds are now stripped from a file's name
812 before searching `auto-mode-alist'.
818 * No special code for Ambassadors, VT-100's and Concept-100's.
820 Emacs now controls these terminals based on the termcap entry, like
821 all other terminals. Formerly it did not refer to the termcap entries
822 for those terminal types, and often the termcap entries for those
823 terminals are wrong or inadequate. If you experience worse behavior
824 on these terminals than in version 15, you can probably correct it by
825 fixing up the termcap entry. See ./TERMS for more info.
827 See ./TERMS in any case if you find that some terminal does not work
828 right with Emacs now.
830 * Minibuffer default completion character is TAB (and not ESC).
832 So that ESC can be used in minibuffer for more useful prefix commands.
834 * C-z suspends Emacs in all modes.
836 Formerly, C-z was redefined for other purposes by certain modes,
837 such as Buffer Menu mode. Now other keys are used for those purposes,
838 to keep the meaning of C-z uniform.
840 * C-x ESC (repeat-complex-command) allows editing the command it repeats.
842 Instead of asking for confirmation to re-execute a command from the
843 command history, the command is placed, in its Lisp form, into the
844 minibuffer for editing. You can confirm by typing RETURN, change some
845 arguments and then confirm, or abort with C-g.
847 * Incremental search does less redisplay on slow terminals.
849 If the terminal baud rate is <= the value of `isearch-slow-speed',
850 incremental searching outside the text on the screen creates
851 a single-line window and uses that to display the line on which
852 a match has been found. Exiting or quitting the search restores
853 the previous window configuration and redisplays the window you
856 The initial value of `isearch-slow-speed' is 1200.
858 This feature is courtesy of crl@purdue.
860 * Recursive minibuffers not allowed.
862 If the minibuffer window is selected, most commands that would
863 use the minibuffer gets an error instead. (Specific commands
864 may override this feature and therefore still be allowed.)
866 Strictly speaking, recursive entry to the minibuffer is still
867 possible, because you can switch to another window after
868 entering the minibuffer, and then minibuffer-using commands
869 are allowed. This is still allowed by a deliberate decision:
870 if you know enough to switch windows while in the minibuffer,
871 you can probably understand recursive minibuffers.
873 This may be overridden by binding the variable
874 `enable-recursive-minibuffers' to t.
876 * New major mode Emacs-Lisp mode, for editing Lisp code to run in Emacs.
878 The mode in which emacs lisp files is edited is now called emacs-lisp-mode
879 and is distinct from lisp-mode. The latter is intended for use with
880 lisps external to emacs.
882 The hook which is funcalled (if non-nil) on entry to elisp-mode is now
883 called emacs-lisp-mode-hook. A consequence of this changes is that
884 .emacs init files which set the value of lisp-mode-hook may need to be
885 changed to use the new names.
887 * Correct matching of parentheses is checked on insertion.
889 When you insert a close-paren, the matching open-paren
890 is checked for validity. The close paren must be the kind
891 of close-paren that the open-paren says it should match.
892 Otherwise, a warning message is printed. close-paren immediately
893 preceded by quoting backslash syntax character is not matched.
895 This feature was originally written by shane@mit-ajax.
897 * M-x list-command-history
898 * M-x command-history-mode
899 * M-x electric-command-history
901 `list-command-history' displays forms from the command history subject
902 to user controlled filtering and limit on number of forms. It leaves
903 the buffer in `command-history-mode'. M-x command-history-mode
904 recomputes the command history each time it is invoked via
905 `list-command-history'. It is like Emacs-Lisp mode except that characters
906 don't insert themselves and provision is made for re-evaluating an
907 expression from the list. `electric-command-history' pops up a type
908 out window with the command history displayed. If the very next
909 character is Space, the window goes away and the previous window
910 configuration is restored. Otherwise you can move around in the
911 history and select an expression for evaluation *inside* the buffer
912 which invoked `electric-command-history'. The original window
913 configuration is restored on exit unless the command selected changes
918 Enters a temporary major mode (the previous major mode is remembered
919 and can is restored on exit) designed for editing pictures and tables.
920 Printing characters replace rather than insert themselves with motion
921 afterwards that is user controlled (you can specify any of the 8
922 compass directions). Special commands for movement are provided.
923 Special commands for hacking tabs and tab stops are provided. Special
924 commands for killing rectangles and overlaying them are provided. See
925 the documentation of function edit-picture for more details.
927 Calls value of `edit-picture-hook' on entry if non-nil.
929 * Stupid C-s/C-q `flow control' supported.
931 Do (set-input-mode nil t) to tell Emacs to use CBREAK mode and interpret
932 C-s and C-q as flow control commands. (set-input-mode t nil) switches
933 back to interrupt-driven input. (set-input-mode nil nil) uses CBREAK
934 mode but no `flow control'; this may make it easier to run Emacs under
935 certain debuggers that have trouble dealing with inferiors that use SIGIO.
937 CBREAK mode has certain inherent disadvantages, which are why it is
940 Meta-keys are ignored; CBREAK mode discards the 8th bit of
943 Control-G as keyboard input discards buffered output,
944 and therefore can cause incorrect screen updating.
946 The use of `flow control' has its own additional disadvantage: the
947 characters C-s and C-q are not available as editing commands. You can
948 partially compensate for this by setting up a keyboard-translate-table
949 (see file ONEWS) that maps two other characters (such as C-^ and C-\) into
950 C-s and C-q. Of course, C-^ and C-\ are commonly used as escape
951 characters in remote-terminal programs. You really can't win except
952 by getting rid of this sort of `flow control.'
954 The configuration switch CBREAK_INPUT is now eliminated.
955 INTERRUPT_INPUT exists only to specify the default mode of operation;
956 #define it to make interrupt-driven input the default.
958 * Completion of directory names provides a slash.
960 If file name completion yields the name of a directory,
961 a slash is appended to it.
963 * Undo can clear modified-flag.
965 If you undo changes in a buffer back to a state in which the
966 buffer was not considered "modified", then it is labeled as
967 once again "unmodified".
971 This command creates an inferior Lisp process whose input and output
972 appear in the Emacs buffer named `*lisp*'. That buffer uses a major mode
973 called inferior-lisp-mode, which has many of the commands of lisp-mode
974 and those of shell-mode. Calls the value of shell-mode-hook and
975 lisp-mode-hook, in that order, if non-nil.
977 Meanwhile, in lisp-mode, the command C-M-x is defined to
978 send the current defun as input to the `*lisp*' subprocess.
980 * Mode line says `Narrow' when buffer is clipped.
982 If a buffer has a clipping restriction (made by `narrow-to-region')
983 then its mode line contains the word `Narrow' after the major and
986 * Mode line says `Abbrev' when abbrev mode is on.
988 * add-change-log-entry takes prefix argument
990 Giving a prefix argument makes it prompt for login name, full name,
991 and site name, with defaults. Otherwise the defaults are used
992 with no confirmation.
994 * M-x view-buffer and M-x view-file
996 view-buffer selects the named buffer, view-file finds the named file; the
997 resulting buffer is placed into view-mode (a recursive edit). The normal
998 emacs commands are not available. Instead a set of special commands is
999 provided which facilitate moving around in the buffer, searching and
1000 scrolling by screenfuls. Exiting view-mode returns to the buffer in which
1001 the view-file or view-buffer command was given.
1002 Type ? or h when viewing for a complete list of view commands.
1003 Each calls value of `view-hook' if non-nil on entry.
1005 written by shane@mit-ajax.
1007 * New key commands in dired.
1009 `v' views (like more) the file on the current line.
1010 `#' marks auto-save files for deletion.
1011 `~' marks backup files for deletion.
1012 `r' renames a file and updates the directory listing if the
1013 file is renamed to same directory.
1014 `c' copies a file and updates the directory listing if the file is
1015 copied to the same directory.
1017 * New function `electric-buffer-list'.
1019 This pops up a buffer describing the set of emacs buffers.
1020 Immediately typing space makes the buffer list go away and returns
1021 to the buffer and window which were previously selected.
1023 Otherwise one may use the c-p and c-n commands to move around in the
1024 buffer-list buffer and type Space or C-z to select the buffer on the
1025 cursor's line. There are a number of other commands which are the same
1026 as those of buffer-menu-mode.
1028 This is a useful thing to bind to c-x c-b in your `.emacs' file if the
1029 rather non-standard `electric' behavior of the buffer list suits your taste.
1030 Type C-h after invoking electric-buffer-list for more information.
1032 Calls value of `electric-buffer-menu-mode-hook' if non-nil on entry.
1033 Calls value of `after-electric-buffer-menu' on exit (select) if non-nil.
1035 Changes in version 16 for mail reading and sending
1037 * sendmail prefix character is C-c (and not C-z). New command C-c w.
1039 For instance C-c C-c (or C-c C-s) sends mail now rather than C-z C-z.
1040 C-c w inserts your `signature' (contents of ~/.signature) at the end
1043 * New feature in C-c y command in sending mail.
1045 C-c y is the command to insert the message being replied to.
1046 Normally it deletes most header fields and indents everything
1049 Now, C-c y does not delete header fields or indent.
1050 C-c y with any other numeric argument does delete most header
1051 fields, but indents by the amount specified in the argument.
1053 * C-r command in Rmail edits current message.
1055 It does this by switching to a different major mode
1056 which is nearly the same as Text mode. The only difference
1057 between it and text mode are the two command C-c and C-].
1058 C-c is defined to switch back to Rmail mode, and C-]
1059 is defined to restore the original contents of the message
1060 and then switch back to Rmail mode.
1062 C-c and C-] are the only ways "back into Rmail", but you
1063 can switch to other buffers and edit them as usual.
1064 C-r in Rmail changes only the handling of the Rmail buffer.
1066 * Rmail command `t' toggles header display.
1068 Normally Rmail reformats messages to hide most header fields.
1069 `t' switches to display of all the header fields of the
1070 current message, as long as it remains current.
1071 Another `t' switches back to the usual display.
1073 * Rmail command '>' goes to the last message.
1075 * Rmail commands `a' and `k' set message attributes.
1076 `a' adds an attribute and `k' removes one. You specify
1077 the attribute by name. You can specify either a built-in
1078 flag such as "deleted" or "filed", or a user-defined keyword
1079 (anything not recognized as built-in).
1081 * Rmail commands `l' and `L' summarize by attributes.
1083 These commands create a summary with one line per message,
1084 like `h', but they list only some of the messages. You
1085 specify which attribute (for `l') or attributes (for `L')
1086 the messages should have.
1088 * Rmail can parse mmdf mail files.
1090 * Interface to MH mail system.
1092 mh-e is a front end for GNU emacs and the MH mail system. It
1093 provides a friendly and convenient interface to the MH commands.
1095 To read mail, invoke mh-rmail. This will inc new mail and display the
1096 scan listing on the screen. To see a summary of the mh-e commands,
1097 type ?. Help is available through the usual facilities.
1099 To send mail, invoke mh-smail.
1101 mh-e requires a copy of MH.5 that has been compiled with the MHE
1104 From larus@berkeley.
1106 New hooks and parameters in version 16
1108 * New variable `blink-matching-paren-distance'.
1110 This is the maximum number of characters to search for
1111 an open-paren to match an inserted close-paren.
1112 The matching open-paren is shown and checked if it is found
1113 within this distance.
1115 `nil' means search all the way to the beginning of the buffer.
1116 In this case, a warning message is printed if no matching
1117 open-paren is found.
1119 This feature was originally written by shane@mit-ajax.
1121 * New variable `find-file-run-dired'
1123 If nil, find-file will report an error if an attempt to visit a
1124 directory is detected; otherwise, it runs dired on that directory.
1127 * Variable `dired-listing-switches' holds switches given to `ls' by dired.
1129 The value should be a string containing `-' followed by letters.
1130 The letter `l' had better be included and letter 'F' had better be excluded!
1131 The default is "-al".
1133 This feature was originally written by shane@mit-ajax.
1135 * New variable `display-time-day-and-date'.
1137 If this variable is set non-`nil', the function M-x display-time
1138 displays the day and date, as well as the time.
1140 * New parameter `c-continued-statement-indent'.
1142 This controls the extra indentation given to a line
1143 that continues a C statement started on the previous line.
1144 By default it is 2, which is why you would see
1150 * Changed meaning of `c-indent-level'.
1152 The value of `c-brace-offset' used to be
1153 subtracted from the value of `c-indent-level' whenever
1154 that value was used. Now it is not.
1156 As a result, `c-indent-level' is now the offset of
1157 statements within a block, relative to the line containing
1158 the open-brace that starts the block.
1160 * turn-on-auto-fill is useful value for text-mode-hook.
1162 (setq text-mode-hook 'turn-on-auto-fill)
1163 is all you have to do to make sure Auto Fill mode is turned
1164 on whenever you enter Text mode.
1166 * Parameter explicit-shell-file-name for M-x shell.
1168 This variable, if non-nil, specifies the file name to use
1169 for the shell to run if you do M-x shell.
1171 Changes in version 16 affecting Lisp programming:
1173 * Documentation strings adapt to customization.
1175 Often the documentation string for a command wants to mention
1176 another command. Simply stating the other command as a
1177 character sequence has a disadvantage: if the user customizes
1178 Emacs by moving that function to a different command, the
1179 cross reference in the documentation becomes wrong.
1181 A new feature allows you to write the documentation string
1182 using a function name, and the command to run that function
1183 is looked up when the documentation is printed.
1185 If a documentation string contains `\[' (two characters) then
1186 the following text, up to the next `]', is taken as a function name.
1187 Instead of printing that function name, the command that runs it is printed.
1188 (M-x is used to construct a command if no shorter one exists.)
1190 For example, instead of putting `C-n' in a documentation string
1191 to refer to the C-n command, put in `\[next-line]'. (In practice
1192 you will need to quote the backslash with another backslash,
1193 due to the syntax for strings in Lisp and C.)
1195 To include the literal characters `\[' in a documentation string,
1196 precede them with `\='. To include the characters `\=', precede
1197 them with `\='. For example, "\\=\\= is the way to quote \\=\\["
1198 will come out as `\= is the way to quote \['.
1200 The new function `substitute-command-keys' takes a string possibly
1201 contaning \[...] constructs and replaces those constructs with
1202 the key sequences they currently stand for.
1204 * Primitives `find-line-comment' and `find-line-comment-body' flushed.
1206 Search for the value of `comment-start-skip' if you want to find
1207 whether and where a line has a comment.
1209 * New function `auto-save-file-name-p'
1211 Should return non-`nil' if given a string which is the name of an
1212 auto-save file (sans directory name). If you redefine
1213 `make-auto-save-file-name', you should redefine this accordingly. By
1214 default, this function returns `t' for filenames beginning with
1217 * The value of `exec-directory' now ends in a slash.
1219 This is to be compatible with most directory names in GNU Emacs.
1221 * Dribble files and termscript files.
1223 (open-dribble-file FILE) opens a dribble file named FILE. When a
1224 dribble file is open, every character Emacs reads from the terminal is
1225 written to the dribble file.
1227 (open-termscript FILE) opens a termscript file named FILE. When a
1228 termscript file is open, all characters sent to the terminal by Emacs
1229 are also written in the termscript file.
1231 The two of these together are very useful for debugging Emacs problems
1234 * Upper case command characters by default are same as lower case.
1236 If a character in a command is an upper case letter, and is not defined,
1237 Emacs uses the definition of the corresponding lower case letter.
1238 For example, if C-x U is not directly undefined, it is treated as
1239 a synonym for C-x u (undo).
1241 * Undefined function errors versus undefined variable errors.
1243 Void-symbol errors now say "boundp" if the symbol's value was void
1244 or "fboundp" if the function definition was void.
1246 * New function `bury-buffer'.
1248 The new function `bury-buffer' takes one argument, a buffer object,
1249 and puts that buffer at the end of the internal list of buffers.
1250 So it is the least preferred candidate for use as the default value
1251 of C-x b, or for other-buffer to return.
1253 * Already-displayed buffers have low priority for display.
1255 When a buffer is chosen automatically for display, or to be the
1256 default in C-x b, buffers already displayed in windows have lower
1257 priority than buffers not currently visible.
1259 * `set-window-start' accepts a third argument NOFORCE.
1261 This argument, if non-nil, prevents the window's force_start flag
1262 from being set. Setting the force_start flag causes the next
1263 redisplay to insist on starting display at the specified starting
1264 point, even if dot must be moved to get it onto the screen.
1266 * New function `send-string-to-terminal'.
1268 This function takes one argument, a string, and outputs its contents
1269 to the terminal exactly as specified: control characters, escape
1272 * Keypad put in command mode.
1274 The terminal's keypad is now put into command mode, as opposed to
1275 numeric mode, while Emacs is running. This is done by means of the
1276 termcap `ks' and `ke' strings.
1278 * New function `generate-new-buffer'
1280 This function takes a string as an argument NAME and looks for a
1281 creates and returns a buffer called NAME if one did not already exist.
1282 Otherwise, it successively tries appending suffixes of the form "<1>",
1283 "<2>" etc to NAME until it creates a string which does not name an
1284 existing buffer. A new buffer with that name is the created and returned.
1286 * New function `prin1-to-string'
1287 This function takes one argument, a lisp object, and returns a string
1288 containing that object's printed representation, such as `prin1'
1291 * New function `read-from-minibuffer'
1292 Lets you supply a prompt, initial-contents, a keymap, and specify
1293 whether the result should be interpreted as a string or a lisp object.
1295 Old functions `read-minibuffer', `eval-minibuffer', `read-string' all
1296 take second optional string argument which is initial contents of
1299 * minibuffer variable names changed (names of keymaps)
1301 minibuf-local-map -> minibuffer-local-map
1302 minibuf-local-ns-map -> minibuffer-local-ns-map
1303 minibuf-local-completion-map -> minibuffer-local-completion-map
1304 minibuf-local-must-match-map -> minibuffer-local-must-match-map
1306 Changes in version 16 affecting configuring and building Emacs
1308 * Configuration switch VT100_INVERSE eliminated.
1310 You can control the use of inverse video on any terminal by setting
1311 the variable `inverse-video', or by changing the termcap entry. If
1312 you like, set `inverse-video' in your `.emacs' file based on
1313 examination of (getenv "TERM").
1315 * New switch `-batch' makes Emacs run noninteractively.
1317 If the switch `-batch' is used, Emacs treats its standard output
1318 and input like ordinary files (even if they are a terminal).
1319 It does not display buffers or windows; the only output to standard output
1320 is what would appear as messages in the echo area, and each
1321 message is followed by a newline.
1323 The terminal modes are not changed, so that C-z and C-c retain
1324 their normal Unix meanings. Emacs does still read commands from
1325 the terminal, but the idea of `-batch' is that you use it with
1326 other command line arguments that tell Emacs a complete task to perform,
1327 including killing itself. `-kill' used as the last argument is a good
1328 way to accomplish this.
1330 The Lisp variable `noninteractive' is now defined, to be `nil'
1331 except when `-batch' has been specified.
1333 * Emacs can be built with output redirected to a file.
1335 This is because -batch (see above) is now used in building Emacs.
1341 * Emacs now runs on Sun and Megatest 68000 systems;
1342 also on at least one 16000 system running 4.2.
1344 * Emacs now alters the output-start and output-stop characters
1345 to prevent C-s and C-q from being considered as flow control
1346 by cretinous rlogin software in 4.2.
1348 * It is now possible convert Mocklisp code (for Gosling Emacs) to Lisp code
1349 that can run in GNU Emacs. M-x convert-mocklisp-buffer
1350 converts the contents of the current buffer from Mocklisp to
1351 GNU Emacs Lisp. You should then save the converted buffer with C-x C-w
1352 under a name ending in ".el"
1354 There are probably some Mocklisp constructs that are not handled.
1355 If you encounter one, feel free to report the failure as a bug.
1356 The construct will be handled in a future Emacs release, if that is not
1359 Note that lisp code converted from Mocklisp code will not necessarily
1360 run as fast as code specifically written for GNU Emacs, nor will it use
1361 the many features of GNU Emacs which are not present in Gosling's emacs.
1362 (In particular, the byte-compiler (m-x byte-compile-file) knows little
1363 about compilation of code directly converted from mocklisp.)
1364 It is envisaged that old mocklisp code will be incrementally converted
1365 to GNU lisp code, with M-x convert-mocklisp-buffer being the first
1366 step in this process.
1368 * Control-x n (narrow-to-region) is now by default a disabled command.
1370 This means that, if you issue this command, it will ask whether
1371 you really mean it. You have the opportunity to enable the
1372 command permanently at that time, so you will not be asked again.
1373 This will place the form "(put 'narrow-to-region 'disabled nil)" in your
1376 * Tags now prompts for the tag table file name to use.
1378 All the tags commands ask for the tag table file name
1379 if you have not yet specified one.
1381 Also, the command M-x visit-tag-table can now be used to
1382 specify the tag table file name initially, or to switch
1385 * If truncate-partial-width-windows is non-nil (as it initially is),
1386 all windows less than the full screen width (that is,
1387 made by side-by-side splitting) truncate lines rather than continuing
1390 * Emacs now checks for Lisp stack overflow to avoid fatal errors.
1391 The depth in eval, apply and funcall may not exceed max-lisp-eval-depth.
1392 The depth in variable bindings and unwind-protects may not exceed
1393 max-specpdl-size. If either limit is exceeded, an error occurs.
1394 You can set the limits to larger values if you wish, but if you make them
1395 too large, you are vulnerable to a fatal error if you invoke
1396 Lisp code that does infinite recursion.
1398 * New hooks find-file-hook and write-file-hook.
1399 Both of these variables if non-nil should be functions of no arguments.
1400 At the time they are called (current-buffer) will be the buffer being
1401 read or written respectively.
1403 find-file-hook is called whenever a file is read into its own buffer,
1404 such as by calling find-file, revert-buffer, etc. It is not called by
1405 functions such as insert-file which do not read the file into a buffer of
1407 find-file-hook is called after the file has been read in and its
1408 local variables (if any) have been processed.
1410 write-file-hook is called just before writing out a file from a buffer.
1412 * The initial value of shell-prompt-pattern is now "^[^#$%>]*[#$%>] *"
1414 * If the .emacs file sets inhibit-startup-message to non-nil,
1415 the messages normally printed by Emacs at startup time
1418 * Facility for run-time conditionalization on the basis of emacs features.
1420 The new variable features is a list of symbols which represent "features"
1421 of the executing emacs, for use in run-time conditionalization.
1423 The function featurep of one argument may be used to test for the
1424 presence of a feature. It is just the same as
1425 (not (null (memq FEATURE features))) where FEATURE is its argument.
1426 For example, (if (featurep 'magic-window-hack)
1427 (transmogrify-window 'vertical)
1428 (split-window-vertically))
1430 The function provide of one argument "announces" that FEATURE is present.
1431 It is much the same as (if (not (featurep FEATURE))
1432 (setq features (cons FEATURE features)))
1434 The function require with arguments FEATURE and FILE-NAME loads FILE-NAME
1435 (which should contain the form (provide FEATURE)) unless FEATURE is present.
1436 It is much the same as (if (not (featurep FEATURE))
1437 (progn (load FILE-NAME)
1438 (if (not featurep FEATURE) (error ...))))
1439 FILE-NAME is optional and defaults to FEATURE.
1441 * New function load-average.
1443 This returns a list of three integers, which are
1444 the current 1 minute, 5 minute and 15 minute load averages,
1445 each multiplied by a hundred (since normally they are floating
1448 * Per-terminal libraries loaded automatically.
1450 Emacs when starting up on terminal type T automatically loads
1451 a library named term-T. T is the value of the TERM environment variable.
1452 Thus, on terminal type vt100, Emacs would do (load "term-vt100" t t).
1453 Such libraries are good places to set the character translation table.
1455 It is a bad idea to redefine lots of commands in a per-terminal library,
1456 since this affects all users. Instead, define a command to do the
1457 redefinitions and let the user's init file, which is loaded later,
1458 call that command or not, as the user prefers.
1460 * Programmer's note: detecting killed buffers.
1462 Buffers are eliminated by explicitly killing them, using
1463 the function kill-buffer. This does not eliminate or affect
1464 the pointers to the buffer which may exist in list structure.
1465 If you have a pointer to a buffer and wish to tell whether
1466 the buffer has been killed, use the function buffer-name.
1467 It returns nil on a killed buffer, and a string on a live buffer.
1469 * New ways to access the last command input character.
1471 The function last-key-struck, which used to return the last
1472 input character that was read by command input, is eliminated.
1473 Instead, you can find this information as the value of the
1474 variable last-command-char. (This variable used to be called
1477 Another new variable, last-input-char, holds the last character
1478 read from the command input stream regardless of what it was
1479 read for. last-input-char and last-command-char are different
1480 only inside a command that has called read-char to read input.
1482 * The new switch -kill causes Emacs to exit after processing the
1483 preceding command line arguments. Thus,
1484 emacs -l lib data -e do-it -kill
1485 means to load lib, find file data, call do-it on no arguments,
1488 * The config.h file has been modularized.
1490 Options that depend on the machine you are running on are defined
1491 in a file whose name starts with "m-", such as m-vax.h.
1492 Options that depend on the operating system software version you are
1493 running on are defined in a file whose name starts with "s-",
1496 config.h includes one m- file and one s- file. It also defines a
1497 few other options whose values do not follow from the machine type
1498 and system type being used. Installers normally will have to
1499 select the correct m- and s- files but will never have to change their
1502 * Termcap AL and DL strings are understood.
1504 If the termcap entry defines AL and DL strings, for insertion
1505 and deletion of multiple lines in one blow, Emacs now uses them.
1506 This matters most on certain bit map display terminals for which
1507 scrolling is comparatively slow.
1509 * Bias against scrolling screen far on fast terminals.
1511 Emacs now prefers to redraw a few lines rather than
1512 shift them a long distance on the screen, when the terminal is fast.
1514 * New major mode, mim-mode.
1516 This major mode is for editing MDL code. Perhaps a MDL
1517 user can explain why it is not called mdl-mode.
1518 You must load the library mim-mode explicitly to use this.
1520 * GNU documentation formatter `texinfo'.
1522 The `texinfo' library defines a format for documentation
1523 files which can be passed through Tex to make a printed manual
1524 or passed through texinfo to make an Info file. Texinfo is
1525 documented fully by its own Info file; compare this file
1526 with its source, texinfo.texinfo, for additional guidance.
1528 All documentation files for GNU utilities should be written
1529 in texinfo input format.
1531 Tex processing of texinfo files requires the Botex macro package.
1532 This is not ready for distribution yet, but will appear at
1535 * New function read-from-string (emacs 15.29)
1537 read-from-string takes three arguments: a string to read from,
1538 and optionally start and end indices which delimit a substring
1539 from which to read. (They default to 0 and the length of the string,
1542 This function returns a cons cell whose car is the object produced
1543 by reading from the string and whose cdr is a number giving the
1544 index in the string of the first character not read. That index may
1545 be passed as the second argument to a later call to read-from-string
1546 to read the next form represented by the string.
1548 In addition, the function read now accepts a string as its argument.
1549 In this case, it calls read-from-string on the whole string, and
1550 returns the car of the result (ie the actual object read.)
1556 * Completion now prints various messages such as [Sole Completion]
1557 or [Next Character Not Unique] to describe the results obtained.
1558 These messages appear after the text in the minibuffer, and remain
1559 on the screen until a few seconds go by or you type a key.
1561 * The buffer-read-only flag is implemented.
1562 Setting or binding this per-buffer variable to a non-nil value
1563 makes illegal any operation which would modify the textual content of
1564 the buffer. (Such operations signal a buffer-read-only error)
1565 The read-only state of a buffer may be altered using toggle-read-only
1567 The buffers used by Rmail, Dired, Rnews, and Info are now read-only
1568 by default to prevent accidental damage to the information in those
1571 * Functions car-safe and cdr-safe.
1572 These functions are like car and cdr when the argument is a cons.
1573 Given an argument not a cons, car-safe always returns nil, with
1574 no error; the same for cdr-safe.
1576 * The new function user-real-login-name returns the name corresponding
1577 to the real uid of the Emacs process. This is usually the same
1578 as what user-login-name returns; however, when Emacs is invoked
1579 from su, user-real-login-name returns "root" but user-login-name
1580 returns the name of the user who invoked su.
1586 * There is a new version numbering scheme.
1588 What used to be the first version number, which was 1,
1589 has been discarded since it does not seem that I need three
1590 levels of version number.
1592 However, a new third version number has been added to represent
1593 changes by user sites. This number will always be zero in
1594 Emacs when I distribute it; it will be incremented each time
1595 Emacs is built at another site.
1597 * There is now a reader syntax for Meta characters:
1598 \M-CHAR means CHAR or'ed with the Meta bit. For example:
1601 ?\M-\n is (+ ?\n 128)
1602 ?\M-\^f is (+ ?\^f 128)
1604 This syntax can be used in strings too. Note, however, that
1605 Meta characters are not meaningful in key sequences being passed
1606 to define-key or lookup-key; you must use ESC characters (\e)
1609 ?\C- can be used likewise for control characters. (13.9)
1611 * Installation change
1612 The string "../lisp" now adds to the front of the load-path
1613 used for searching for Lisp files during Emacs initialization.
1614 It used to replace the path specified in paths.h entirely.
1615 Now the directory ../lisp is searched first and the directories
1616 specified in paths.h are searched afterward.
1620 Changes in Emacs 1.12
1622 * There is a new installation procedure.
1623 See the file INSTALL that comes in the top level
1624 directory in the tar file or tape.
1626 * The Meta key is now supported on terminals that have it.
1627 This is a shift key which causes the high bit to be turned on
1628 in all input characters typed while it is held down.
1630 read-char now returns a value in the range 128-255 if
1631 a Meta character is typed. When interpreted as command
1632 input, a Meta character is equivalent to a two character
1633 sequence, the meta prefix character followed by the un-metized
1634 character (Meta-G unmetized is G).
1636 The meta prefix character
1637 is specified by the value of the variable meta-prefix-char.
1638 If this character (normally Escape) has been redefined locally
1639 with a non-prefix definition (such as happens in completing
1640 minibuffers) then the local redefinition is suppressed when
1641 the character is not the last one in a key sequence.
1642 So the local redefinition is effective if you type the character
1643 explicitly, but not effective if the character comes from
1644 the use of the Meta key.
1646 * `-' is no longer a completion command in the minibuffer.
1647 It is an ordinary self-inserting character.
1649 * The list load-path of directories load to search for Lisp files
1650 is now controlled by the EMACSLOADPATH environment variable
1651 [[ Note this was originally EMACS-LOAD-PATH and has been changed
1652 again; sh does not deal properly with hyphens in env variable names]]
1653 rather than the EPATH environment variable. This is to avoid
1654 conflicts with other Emacses.
1656 While Emacs is being built initially, the load-path
1657 is now just ("../lisp"), ignoring paths.h. It does not
1658 ignore EMACSLOADPATH, however; you should avoid having
1659 this variable set while building Emacs.
1661 * You can now specify a translation table for keyboard
1662 input characters, as a way of exchanging or substituting
1663 keys on the keyboard.
1665 If the value of keyboard-translate-table is a string,
1666 every character received from the keyboard is used as an
1667 index in that string, and the character at that index in
1668 the string is used as input instead of what was actually
1669 typed. If the actual input character is >= the length of
1670 the string, it is used unchanged.
1672 One way this feature can be used is to fix bad keyboard
1673 designs. For example, on some terminals, Delete is
1674 Shift-Underscore. Since Delete is a more useful character
1675 than Underscore, it is an improvement to make the unshifted
1676 character Delete and the shifted one Underscore. This can
1679 ;; First make a translate table that does the identity translation.
1680 (setq keyboard-translate-table (make-string 128 0))
1683 (aset keyboard-translate-table i i)
1686 ;; Now alter translations of some characters.
1687 (aset keyboard-translate-table ?\_ ?\^?)
1688 (aset keyboard-translate-table ?\^? ?\_)
1690 If your terminal has a Meta key and can therefore send
1691 codes up to 255, Meta characters are translated through
1692 elements 128 through 255 of the translate table, and therefore
1693 are translated independently of the corresponding non-Meta
1694 characters. You must therefore establish translations
1695 independently for the Meta characters if you want them too:
1697 ;; First make a translate table that does the identity translation.
1698 (setq keyboard-translate-table (make-string 256 0))
1701 (aset keyboard-translate-table i i)
1704 ;; Now alter translations of some characters.
1705 (aset keyboard-translate-table ?\_ ?\^?)
1706 (aset keyboard-translate-table ?\^? ?\_)
1708 ;; Now alter translations of some Meta characters.
1709 (aset keyboard-translate-table (+ 128 ?\_) (+ 128 ?\^?))
1710 (aset keyboard-translate-table (+ 128 ?\^?) (+ 128 ?\_))
1712 * (process-kill-without-query PROCESS)
1714 This marks the process so that, when you kill Emacs,
1715 you will not on its account be queried about active subprocesses.
1719 Changes in Emacs 1.11
1721 * The commands C-c and C-z have been interchanged,
1722 for greater compatibility with normal Unix usage.
1723 C-z now runs suspend-emacs and C-c runs exit-recursive-edit.
1725 * The value returned by file-name-directory now ends
1726 with a slash. (file-name-directory "foo/bar") => "foo/".
1727 This avoids confusing results when dealing with files
1728 in the root directory.
1730 The value of the per-buffer variable default-directory
1731 is also supposed to have a final slash now.
1733 * There are now variables to control the switches passed to
1734 `ls' by the C-x C-d command (list-directory).
1735 list-directory-brief-switches is a string, initially "-CF",
1736 used for brief listings, and list-directory-verbose-switches
1737 is a string, initially "-l", used for verbose ones.
1739 * For Ann Arbor Ambassador terminals, the termcap "ti" string
1740 is now used to initialize the screen geometry on entry to Emacs,
1741 and the "te" string is used to set it back on exit.
1742 If the termcap entry does not define the "ti" or "te" string,
1743 Emacs does what it used to do.
1747 Changes in Emacs 1.10
1749 * GNU Emacs has been made almost 1/3 smaller.
1750 It now dumps out as only 530kbytes on Vax 4.2bsd.
1752 * The term "checkpoint" has been replaced by "auto save"
1753 throughout the function names, variable names and documentation
1756 * The function load now tries appending ".elc" and ".el"
1757 to the specified filename BEFORE it tries the filename
1760 * rmail now makes the mode line display the total number
1761 of messages and the current message number.
1762 The "f" command now means forward a message to another user.
1763 The command to search through all messages for a string is now "F".
1764 The "u" command now means to move back to the previous
1765 message and undelete it. To undelete the selected message, use Meta-u.
1767 * The hyphen character is now equivalent to a Space while
1768 in completing minibuffers. Both mean to complete an additional word.
1770 * The Lisp function error now takes args like format
1771 which are used to construct the error message.
1773 * Redisplay will refuse to start its display at the end of the buffer.
1774 It will pick a new place to display from, rather than use that.
1776 * The value returned by garbage-collect has been changed.
1777 Its first element is no longer a number but a cons,
1778 whose car is the number of cons cells now in use,
1779 and whose cdr is the number of cons cells that have been
1780 made but are now free.
1781 The second element is similar but describes symbols rather than cons cells.
1782 The third element is similar but describes markers.
1784 * The variable buffer-name has been eliminated.
1785 The function buffer-name still exists. This is to prevent
1786 user programs from changing buffer names without going
1787 through the rename-buffer function.
1791 Changes in Emacs 1.9
1793 * When a fill prefix is in effect, paragraphs are started
1794 or separated by lines that do not start with the fill prefix.
1795 Also, a line which consists of the fill prefix followed by
1796 white space separates paragraphs.
1798 * C-x C-v runs the new function find-alternate-file.
1799 It finds the specified file, switches to that buffer,
1800 and kills the previous current buffer. (It requires
1801 confirmation if that buffer had changes.) This is
1802 most useful after you find the wrong file due to a typo.
1804 * Exiting the minibuffer moves the cursor to column 0,
1805 to show you that it has really been exited.
1807 * Meta-g (fill-region) now fills each paragraph in the
1808 region individually. To fill the region as if it were
1809 a single paragraph (for when the paragraph-delimiting mechanism
1810 does the wrong thing), use fill-region-as-paragraph.
1812 * Tab in text mode now runs the function tab-to-tab-stop.
1813 A new mode called indented-text-mode is like text-mode
1814 except that in it Tab runs the function indent-relative,
1815 which indents the line under the previous line.
1816 If auto fill is enabled while in indented-text-mode,
1817 the new lines that it makes are indented.
1819 * Functions kill-rectangle and yank-rectangle.
1820 kill-rectangle deletes the rectangle specified by dot and mark
1821 (or by two arguments) and saves it in the variable killed-rectangle.
1822 yank-rectangle inserts the rectangle in that variable.
1824 Tab characters in a rectangle being saved are replaced
1825 by spaces in such a way that their appearance will
1826 not be changed if the rectangle is later reinserted
1827 at a different column position.
1829 * `+' in a regular expression now means
1830 to repeat the previous expression one or more times.
1831 `?' means to repeat it zero or one time.
1832 They are in all regards like `*' except for the
1833 number of repetitions they match.
1835 \< in a regular expression now matches the null string
1836 when it is at the beginning of a word; \> matches
1837 the null string at the end of a word.
1839 * C-x p narrows the buffer so that only the current page
1842 * C-x ) with argument repeats the kbd macro just
1843 defined that many times, counting the definition
1846 * C-x ( with argument begins defining a kbd macro
1847 starting with the last one defined. It executes that
1848 previous kbd macro initially, just as if you began
1849 by typing it over again.
1851 * C-x q command queries the user during kbd macro execution.
1852 With prefix argument, enters recursive edit,
1853 reading keyboard commands even within a kbd macro.
1854 You can give different commands each time the macro executes.
1855 Without prefix argument, reads a character. Your options are:
1856 Space -- execute the rest of the macro.
1857 Delete -- skip the rest of the macro; start next repetition.
1858 C-d -- skip rest of the macro and don't repeat it any more.
1859 C-r -- enter a recursive edit, then on exit ask again for a character
1860 C-l -- redisplay screen and ask again."
1862 * write-kbd-macro and append-kbd-macro are used to save
1863 a kbd macro definition in a file (as Lisp code to
1864 redefine the macro when the file is loaded).
1865 These commands differ in that write-kbd-macro
1866 discards the previous contents of the file.
1867 If given a prefix argument, both commands
1868 record the keys which invoke the macro as well as the
1871 * The variable global-minor-modes is used to display
1872 strings in the mode line of all buffers. It should be
1873 a list of elements that are conses whose cdrs are strings
1874 to be displayed. This complements the variable
1875 minor-modes, which has the same effect but has a separate
1876 value in each buffer.
1878 * C-x = describes horizontal scrolling in effect, if any.
1880 * Return now auto-fills the line it is ending, in auto fill mode.
1881 Space with zero as argument auto-fills the line before it
1882 just like Space without an argument.
1886 Changes in Emacs 1.8
1888 This release mostly fixes bugs. There are a few new features:
1890 * apropos now sorts the symbols before displaying them.
1891 Also, it returns a list of the symbols found.
1893 apropos now accepts a second arg PRED which should be a function
1894 of one argument; if PRED is non-nil, each symbol is tested
1895 with PRED and only symbols for which PRED returns non-nil
1896 appear in the output or the returned list.
1898 If the third argument to apropos is non-nil, apropos does not
1899 display anything; it merely returns the list of symbols found.
1901 C-h a now runs the new function command-apropos rather than
1902 apropos, and shows only symbols with definitions as commands.
1904 * M-x shell sends the command
1905 if (-f ~/.emacs_NAME)source ~/.emacs_NAME
1906 invisibly to the shell when it starts. Here NAME
1907 is replaced by the name of shell used,
1908 as it came from your ESHELL or SHELL environment variable
1909 but with directory name, if any, removed.
1911 * M-, now runs the command tags-loop-continue, which is used
1912 to resume a terminated tags-search or tags-query-replace.
1916 Changes in Emacs 1.7
1920 * The initial buffer is now called "*scratch*" instead of "scratch",
1921 so that all buffer names used automatically by Emacs now have *'s.
1923 * Undo information is now stored separately for each buffer.
1924 The Undo command (C-x u) always applies to the current
1927 C-_ is now a synonym for C-x u.
1929 (buffer-flush-undo BUFFER) causes undo information not to
1930 be kept for BUFFER, and frees the space that would have
1931 been used to hold it. In any case, no undo information is
1932 kept for buffers whose names start with spaces. (These
1933 buffers also do not appear in the C-x C-b display.)
1935 * Rectangle operations are now implemented.
1936 C-x r stores the rectangle described by dot and mark
1937 into a register; it reads the register name from the keyboard.
1938 C-x g, the command to insert the contents of a register,
1939 can be used to reinsert the rectangle elsewhere.
1941 Other rectangle commands include
1943 insert a blank rectangle in the position and size
1944 described by dot and mark, at its corners;
1945 the existing text is pushed to the right.
1947 replace the rectangle described by dot ane mark
1948 with blanks. The previous text is deleted.
1950 delete the text of the specified rectangle,
1951 moving the text beyond it on each line leftward.
1953 * Side-by-side windows are allowed. Use C-x 5 to split the
1954 current window into two windows side by side.
1955 C-x } makes the selected window ARG columns wider at the
1956 expense of the windows at its sides. C-x { makes the selected
1957 window ARG columns narrower. An argument to C-x 5 specifies
1958 how many columns to give to the leftmost of the two windows made.
1960 C-x 2 now accepts a numeric argument to specify the number of
1961 lines to give to the uppermost of the two windows it makes.
1963 * Horizontal scrolling of the lines in a window is now implemented.
1964 C-x < (scroll-left) scrolls all displayed lines left,
1965 with the numeric argument (default 1) saying how far to scroll.
1966 When the window is scrolled left, some amount of the beginning
1967 of each nonempty line is replaced by an "$".
1968 C-x > scrolls right. If a window has no text hidden at the left
1969 margin, it cannot be scrolled any farther right than that.
1970 When nonzero leftwards scrolling is in effect in a window.
1971 lines are automatically truncated at the window's right margin
1972 regardless of the value of the variable truncate-lines in the
1973 buffer being displayed.
1975 * C-x C-d now uses the default output format of `ls',
1976 which gives just file names in multiple columns.
1977 C-u C-x C-d passes the -l switch to `ls'.
1979 * C-t at the end of a line now exchanges the two preceding characters.
1981 All the transpose commands now interpret zero as an argument
1982 to mean to transpose the textual unit after or around dot
1983 with the one after or around the mark.
1985 * M-! executes a shell command in an inferior shell
1986 and displays the output from it. With a prefix argument,
1987 it inserts the output in the current buffer after dot
1988 and sets the mark after the output. The shell command
1989 gets /dev/null as its standard input.
1991 M-| is like M-! but passes the contents of the region
1992 as input to the shell command. A prefix argument makes
1993 the output from the command replace the contents of the region.
1995 * The mode line will now say "Def" after the major mode
1996 while a keyboard macro is being defined.
1998 * The variable fill-prefix is now used by Meta-q.
1999 Meta-q removes the fill prefix from lines that start with it
2000 before filling, and inserts the fill prefix on each line
2003 The command C-x . sets the fill prefix equal to the text
2004 on the current line before dot.
2006 * The new command Meta-j (indent-new-comment-line),
2007 is like Linefeed (indent-new-line) except when dot is inside a comment;
2008 in that case, Meta-j inserts a comment starter on the new line,
2009 indented under the comment starter above. It also inserts
2010 a comment terminator at the end of the line above,
2011 if the language being edited calls for one.
2013 * Rmail should work correctly now, and has some C-h m documentation.
2017 Changes in Emacs 1.6
2019 * save-buffers-kill-emacs is now on C-x C-c
2020 while C-x C-z does suspend-emacs. This is to make
2021 C-x C-c like the normal Unix meaning of C-c
2022 and C-x C-z like the normal Unix meaning of C-z.
2024 * M-ESC (eval-expression) is now a disabled command by default.
2025 This prevents users who type ESC ESC accidentally from
2026 getting confusing results. Put
2027 (put 'eval-expression 'disabled nil)
2028 in your ~/.emacs file to enable the command.
2030 * Self-inserting text is grouped into bunches for undoing.
2031 Each C-x u command undoes up to 20 consecutive self-inserting
2034 * Help f now uses as a default the function being called
2035 in the innermost Lisp expression that dot is in.
2036 This makes it more convenient to use while writing
2037 Lisp code to run in Emacs.
2038 (If the text around dot does not appear to be a call
2039 to a Lisp function, there is no default.)
2041 Likewise, Help v uses the symbol around or before dot
2042 as a default, if that is a variable name.
2044 * Commands that read filenames now insert the default
2045 directory in the minibuffer, to become part of your input.
2046 This allows you to see what the default is.
2047 You may type a filename which goes at the end of the
2048 default directory, or you may edit the default directory
2049 as you like to create the input you want to give.
2050 You may also type an absolute pathname (starting with /)
2051 or refer to a home directory (input starting with ~)
2052 after the default; the presence of // or /~ causes
2053 everything up through the slash that precedes your
2054 type-in to be ignored.
2056 Returning the default directory without change,
2057 including the terminating slash, requests the use
2058 of the default file name (usually the visited file's name).
2060 Set the variable insert-default-directory to nil
2061 to turn off this feature.
2063 * M-x shell now uses the environment variable ESHELL,
2064 if it exists, as the file name of the shell to run.
2065 If there is no ESHELL variable, the SHELL variable is used.
2066 This is because some shells do not work properly as inferiors
2067 of Emacs (or anything like Emacs).
2069 * A new variable minor-modes now exists, with a separate value
2070 in each buffer. Its value should be an alist of elements
2071 (MODE-FUNCTION-SYMBOL . PRETTY-NAME-STRING), one for each
2072 minor mode that is turned on in the buffer. The pretty
2073 name strings are displayed in the mode line after the name of the
2074 major mode (with spaces between them). The mode function
2075 symbols should be symbols whose function definitions will
2076 turn on the minor mode if given 1 as an argument; they are present
2077 so that Help m can find their documentation strings.
2079 * The format of tag table files has been changed.
2080 The new format enables Emacs to find tags much faster.
2082 A new program, etags, exists to make the kind of
2083 tag table that Emacs wants. etags is invoked just
2084 like ctags; in fact, if you give it any switches,
2085 it does exactly what ctags would do. Give it the
2086 empty switch ("-") to make it act like ctags with no switches.
2088 etags names the tag table file "TAGS" rather than "tags",
2089 so that these tag tables and the standard Unix ones
2092 The tags library can no longer use standard ctags-style
2095 * The file of Lisp code Emacs reads on startup is now
2096 called ~/.emacs rather than ~/.emacs_pro.
2098 * copy-file now gives the copied file the same mode bits
2099 as the original file.
2101 * Output from a process inserted into the process's buffer
2102 no longer sets the buffer's mark. Instead it sets a
2103 marker associated with the process to point to the end
2104 of the inserted text. You can access this marker with
2105 (process-mark PROCESS)
2106 and then either examine its position with marker-position
2107 or set its position with set-marker.
2109 * completing-read takes a new optional fifth argument which,
2110 if non-nil, should be a string of text to insert into
2111 the minibuffer before reading user commands.
2113 * The Lisp function elt now exists:
2114 (elt ARRAY N) is like (aref ARRAY N),
2115 (elt LIST N) is like (nth N LIST).
2117 * rplaca is now a synonym for setcar, and rplacd for setcdr.
2118 eql is now a synonym for eq; it turns out that the Common Lisp
2119 distinction between eq and eql is insignificant in Emacs.
2120 numberp is a new synonym for integerp.
2122 * auto-save has been renamed to auto-save-mode.
2124 * Auto save file names for buffers are now created by the
2125 function make-auto-save-file-name. This is so you can
2126 redefine that function to change the way auto save file names
2129 * expand-file-name no longer discards a final slash.
2130 (expand-file-name "foo" "/lose") => "/lose/foo"
2131 (expand-file-name "foo/" "/lose") => "/lose/foo/"
2133 Also, expand-file-name no longer substitutes $ constructs.
2134 A new function substitute-in-file-name does this. Reading
2135 a file name with read-file-name or the `f' or`F' option
2136 of interactive calling uses substitute-in-file-name
2137 on the file name that was read and returns the result.
2139 All I/O primitives including insert-file-contents and
2140 delete-file call expand-file-name on the file name supplied.
2141 This change makes them considerably faster in the usual case.
2143 * Interactive calling spec strings allow the new code letter 'D'
2144 which means to read a directory name. It is like 'f' except
2145 that the default if the user makes no change in the minibuffer
2146 is to return the current default directory rather than the
2147 current visited file name.
2151 Changes in Emacs 1.5
2153 * suspend-emacs now accepts an optional argument
2154 which is a string to be stuffed as terminal input
2155 to be read by Emacs's superior shell after Emacs exits.
2157 A library called ledit exists which uses this feature
2158 to transmit text to a Lisp job running as a sibling of
2161 * If find-file is given the name of a directory,
2162 it automatically invokes dired on that directory
2163 rather than reading in the binary data that make up
2164 the actual contents of the directory according to Unix.
2166 * Saving an Emacs buffer now preserves the file modes
2167 of any previously existing file with the same name.
2168 This works using new Lisp functions file-modes and
2169 set-file-modes, which can be used to read or set the mode
2172 * The Lisp function cond now exists, with its traditional meaning.
2174 * defvar and defconst now permit the documentation string
2175 to be omitted. defvar also permits the initial value
2176 to be omitted; then it acts only as a comment.
2180 Changes in Emacs 1.4
2182 * Auto-filling now normally indents the new line it creates
2183 by calling indent-according-to-mode. This function, meanwhile,
2184 has in Fundamental and Text modes the effect of making the line
2185 have an indentation of the value of left-margin, a per-buffer variable.
2187 Tab no longer precisely does indent-according-to-mode;
2188 it does that in all modes that supply their own indentation routine,
2189 but in Fundamental, Text and allied modes it inserts a tab character.
2191 * The command M-x grep now invokes grep (on arguments
2192 supplied by the user) and reads the output from grep
2193 asynchronously into a buffer. The command C-x ` can
2194 be used to move to the lines that grep has found.
2195 This is an adaptation of the mechanism used for
2196 running compilations and finding the loci of error messages.
2198 You can now use C-x ` even while grep or compilation
2199 is proceeding; as more matches or error messages arrive,
2200 C-x ` will parse them and be able to find them.
2202 * M-x mail now provides a command to send the message
2203 and "exit"--that is, return to the previously selected
2204 buffer. It is C-z C-z.
2206 * Tab in C mode now tries harder to adapt to all indentation styles.
2207 If the line being indented is a statement that is not the first
2208 one in the containing compound-statement, it is aligned under
2209 the beginning of the first statement.
2211 * The functions screen-width and screen-height return the
2212 total width and height of the screen as it is now being used.
2213 set-screen-width and set-screen-height tell Emacs how big
2214 to assume the screen is; they each take one argument,
2217 * The Lisp function 'function' now exists. function is the
2218 same as quote, except that it serves as a signal to the
2219 Lisp compiler that the argument should be compiled as
2220 a function. Example:
2221 (mapcar (function (lambda (x) (+ x 5))) list)
2223 * The function set-key has been renamed to global-set-key.
2224 undefine-key and local-undefine-key has been renamed to
2225 global-unset-key and local-unset-key.
2227 * Emacs now collects input from asynchronous subprocesses
2228 while waiting in the functions sleep-for and sit-for.
2230 * Shell mode's Newline command attempts to distinguish subshell
2231 prompts from user input when issued in the middle of the buffer.
2232 It no longer reexecutes from dot to the end of the line;
2233 it reeexecutes the entire line minus any prompt.
2234 The prompt is recognized by searching for the value of
2235 shell-prompt-pattern, starting from the beginning of the line.
2236 Anything thus skipped is not reexecuted.
2240 Changes in Emacs 1.3
2242 * An undo facility exists now. Type C-x u to undo a batch of
2243 changes (usually one command's changes, but some commands
2244 such as query-replace divide their changes into multiple
2245 batches. You can repeat C-x u to undo further. As long
2246 as no commands other than C-x u intervene, each one undoes
2247 another batch. A numeric argument to C-x u acts as a repeat
2250 If you keep on undoing, eventually you may be told that
2251 you have used up all the recorded undo information.
2252 Some actions, such as reading in files, discard all
2255 The undo information is not currently stored separately
2256 for each buffer, so it is mainly good if you do something
2257 totally spastic. [This has since been fixed.]
2259 * A learn-by-doing tutorial introduction to Emacs now exists.
2260 Type C-h t to enter it.
2262 * An Info documentation browser exists. Do M-x info to enter it.
2263 It contains a tutorial introduction so that no more documentation
2264 is needed here. As of now, the only documentation in it
2265 is that of Info itself.
2267 * Help k and Help c are now different. Help c prints just the
2268 name of the function which the specified key invokes. Help k
2269 prints the documentation of the function as well.
2271 * A document of the differences between GNU Emacs and Twenex Emacs
2272 now exists. It is called DIFF, in the same directory as this file.
2274 * C mode can now indent comments better, including multi-line ones.
2275 Meta-Control-q now reindents comment lines within the expression
2278 * Insertion of a close-parenthesis now shows the matching open-parenthesis
2279 even if it is off screen, by printing the text following it on its line
2282 * A file can now contain a list of local variable values
2283 to be in effect when the file is edited. See the file DIFF
2284 in the same directory as this file for full details.
2286 * A function nth is defined. It means the same thing as in Common Lisp.
2288 * The function install-command has been renamed to set-key.
2289 It now takes the key sequence as the first argument
2290 and the definition for it as the second argument.
2291 Likewise, local-install-command has been renamed to local-set-key.
2295 Changes in Emacs 1.2
2297 * A Lisp single-stepping and debugging facility exists.
2298 To cause the debugger to be entered when an error
2299 occurs, set the variable debug-on-error non-nil.
2301 To cause the debugger to be entered whenever function foo
2302 is called, do (debug-on-entry 'foo). To cancel this,
2303 do (cancel-debug-on-entry 'foo). debug-on-entry does
2304 not work for primitives (written in C), only functions
2305 written in Lisp. Most standard Emacs commands are in Lisp.
2307 When the debugger is entered, the selected window shows
2308 a buffer called " *Backtrace" which displays a series
2309 of stack frames, most recently entered first. For each
2310 frame, the function name called is shown, usually followed
2311 by the argument values unless arguments are still being
2312 calculated. At the beginning of the buffer is a description
2313 of why the debugger was entered: function entry, function exit,
2314 error, or simply that the user called the function `debug'.
2316 To exit the debugger and return to top level, type `q'.
2318 In the debugger, you can evaluate Lisp expressions by
2319 typing `e'. This is equivalent to `M-ESC'.
2321 When the debugger is entered due to an error, that is
2322 all you can do. When it is entered due to function entry
2323 (such as, requested by debug-on-entry), you have two
2325 Continue execution and reenter debugger after the
2326 completion of the function being entered. Type `c'.
2327 Continue execution but enter the debugger before
2328 the next subexpression. Type `d'.
2330 You will see that some stack frames are marked with *.
2331 This means the debugger will be entered when those
2332 frames exit. You will see the value being returned
2333 in the first line of the backtrace buffer. Your options:
2334 Continue execution, and return that value. Type `c'.
2335 Continue execution, and return a specified value. Type `r'.
2337 You can mark a frame to enter the debugger on exit
2338 with the `b' command, or clear such a mark with `u'.
2340 * Lisp macros now exist.
2341 For example, you can write
2342 (defmacro cadr (arg) (list 'car (list 'cdr arg)))
2343 and then the expression
2350 Changes in Emacs 1.1
2352 * The initial buffer is now called "scratch" and is in a
2353 new major mode, Lisp Interaction mode. This mode is
2354 intended for typing Lisp expressions, evaluating them,
2355 and having the values printed into the buffer.
2357 Type Linefeed after a Lisp expression, to evaluate the
2358 expression and have its value printed into the buffer,
2361 The other commands of Lisp mode are available.
2363 * The C-x C-e command for evaluating the Lisp expression
2364 before dot has been changed to print the value in the
2365 minibuffer line rather than insert it in the buffer.
2366 A numeric argument causes the printed value to appear
2367 in the buffer instead.
2369 * In Lisp mode, the command M-C-x evaluates the defun
2370 containing or following dot. The value is printed in
2373 * The value of a Lisp expression evaluated using M-ESC
2374 is now printed in the minibuffer.
2376 * M-q now runs fill-paragraph, independent of major mode.
2378 * C-h m now prints documentation on the current buffer's
2379 major mode. What it prints is the documentation of the
2380 major mode name as a function. All major modes have been
2381 equipped with documentation that describes all commands
2382 peculiar to the major mode, for this purpose.
2384 * You can display a Unix manual entry with
2385 the M-x manual-entry command.
2387 * You can run a shell, displaying its output in a buffer,
2388 with the M-x shell command. The Return key sends input
2389 to the subshell. Output is printed inserted automatically
2390 in the buffer. Commands C-c, C-d, C-u, C-w and C-z are redefined
2391 for controlling the subshell and its subjobs.
2392 "cd", "pushd" and "popd" commands are recognized as you
2393 enter them, so that the default directory of the Emacs buffer
2394 always remains the same as that of the subshell.
2396 * C-x $ (that's a real dollar sign) controls line-hiding based
2397 on indentation. With a numeric arg N > 0, it causes all lines
2398 indented by N or more columns to become invisible.
2399 They are, effectively, tacked onto the preceding line, where
2400 they are represented by " ..." on the screen.
2401 (The end of the preceding visible line corresponds to a
2402 screen cursor position before the "...". Anywhere in the
2403 invisible lines that follow appears on the screen as a cursor
2404 position after the "...".)
2405 Currently, all editing commands treat invisible lines just
2406 like visible ones, except for C-n and C-p, which have special
2407 code to count visible lines only.
2408 C-x $ with no argument turns off this mode, which in any case
2409 is remembered separately for each buffer.
2411 * Outline mode is another form of selective display.
2412 It is a major mode invoked with M-x outline-mode.
2413 It is intended for editing files that are structured as
2414 outlines, with heading lines (lines that begin with one
2415 or more asterisks) and text lines (all other lines).
2416 The number of asterisks in a heading line are its level;
2417 the subheadings of a heading line are all following heading
2418 lines at higher levels, until but not including the next
2419 heading line at the same or a lower level, regardless
2420 of intervening text lines.
2422 In outline mode, you have commands to hide (remove from display)
2423 or show the text or subheadings under each heading line
2424 independently. Hidden text or subheadings are invisibly
2425 attached to the end of the preceding heading line, so that
2426 if you kill the heading line and yank it back elsewhere
2427 all the invisible lines accompany it.
2429 All editing commands treat hidden outline-mode lines
2430 as part of the preceding visible line.
2432 * C-x C-z runs save-buffers-kill-emacs
2433 offers to save each file buffer, then exits.
2435 * C-c's function is now called suspend-emacs.
2437 * The command C-x m runs mail, which switches to a buffer *mail*
2438 and lets you compose a message to send. C-x 4 m runs mail in
2439 another window. Type C-z C-s in the mail buffer to send the
2440 message according to what you have entered in the buffer.
2442 You must separate the headers from the message text with
2445 * You can now dired partial directories (specified with names
2446 containing *'s, etc, all processed by the shell). Also, you
2447 can dired more than one directory; dired names the buffer
2448 according to the filespec or directory name. Reinvoking
2449 dired on a directory already diredded just switches back to
2450 the same directory used last time; do M-x revert if you want
2451 to read in the current contents of the directory.
2453 C-x d runs dired, and C-x 4 d runs dired in another window.
2455 C-x C-d (list-directory) also allows partial directories now.
2458 Lisp programming changes
2460 * t as an output stream now means "print to the minibuffer".
2461 If there is already text in the minibuffer printed via t
2462 as an output stream, the new text is appended to the old
2463 (or is truncated and lost at the margin). If the minibuffer
2464 contains text put there for some other reason, it is cleared
2467 t is now the top-level value of standard-output.
2469 t as an input stream now means "read via the minibuffer".
2470 The minibuffer is used to read a line of input, with editing,
2471 and this line is then parsed. Any excess not used by `read'
2472 is ignored; each `read' from t reads fresh input.
2473 t is now the top-level value of standard-input.
2475 * A marker may be used as an input stream or an output stream.
2476 The effect is to grab input from where the marker points,
2477 advancing it over the characters read, or to insert output
2478 at the marker and advance it.
2480 * Output from an asynchronous subprocess is now inserted at
2481 the end of the associated buffer, not at the buffer's dot,
2482 and the buffer's mark is set to the end of the inserted output
2483 each time output is inserted.
2485 * (pos-visible-in-window-p POS WINDOW)
2486 returns t if position POS in WINDOW's buffer is in the range
2487 that is being displayed in WINDOW; nil if it is scrolled
2488 vertically out of visibility.
2490 If display in WINDOW is not currently up to date, this function
2491 calculates carefully whether POS would appear if display were
2492 done immediately based on the current (window-start WINDOW).
2494 POS defaults to (dot), and WINDOW to (selected-window).
2496 * Variable buffer-alist replaced by function (buffer-list).
2497 The actual alist of buffers used internally by Emacs is now
2498 no longer accessible, to prevent the user from crashing Emacs
2499 by modifying it. The function buffer-list returns a list
2500 of all existing buffers. Modifying this list cannot hurt anything
2501 as a new list is constructed by each call to buffer-list.
2503 * load now takes an optional third argument NOMSG which, if non-nil,
2504 prevents load from printing a message when it starts and when
2507 * byte-recompile-directory is a new function which finds all
2508 the .elc files in a directory, and regenerates each one which
2509 is older than the corresponding .el (Lisp source) file.
2513 ----------------------------------------------------------------------
2514 This file is part of GNU Emacs.
2516 GNU Emacs is free software: you can redistribute it and/or modify
2517 it under the terms of the GNU General Public License as published by
2518 the Free Software Foundation, either version 3 of the License, or
2519 (at your option) any later version.
2521 GNU Emacs is distributed in the hope that it will be useful,
2522 but WITHOUT ANY WARRANTY; without even the implied warranty of
2523 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
2524 GNU General Public License for more details.
2526 You should have received a copy of the GNU General Public License
2527 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.