NEWS.~14~ 34 KB

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  1. GNU Emacs NEWS -- history of user-visible changes. 13-Sep-1986
  2. Copyright (C) 1986 Richard M. Stallman.
  3. See the end for copying conditions.
  4. Changes in Emacs 18
  5. * Additional systems and machines are supported.
  6. GNU Emacs now runs on Vax VMS (Vomit Making System). However,
  7. many facilities that are normally implemented by running subprocesses
  8. do not work yet. This includes listing a directory and sending mail.
  9. There are features for running subprocesses but they are incompatible
  10. with those on Unix.
  11. VMS wizards are asked to work on making the subprocess facilities
  12. more upward compatible with those on Unix, and also to rewrite their
  13. internals to use the same Lisp objects that are used on Unix to
  14. represent processes.
  15. In addition, the TI Nu machine running Unix system V, the AT&T 3b20,
  16. and the Wicat, Masscomp and Gould Unix systems are now supported. The
  17. IBM PC-RT is supported under 4.2, but not yet under system V. The GEC
  18. 93 is close to working. The port for the Elxsi is partly merged. See
  19. the file MACHINES for full status information and machine-specific
  20. installation advice.
  21. * Display changes.
  22. When you delete or kill or alter text that reaches to the top of the
  23. screen or above it, so that display would start in the middle of a
  24. line, Emacs will usually attempt to scroll the text so that display
  25. starts at the beginning of a line again.
  26. * File loading changes.
  27. `load' now considers all possible suffixes (`.elc', `.el' and none)
  28. for each directory in `load-path' before going on to the next directory.
  29. It now accepts an optional fourth argument which, if non-nil, says to
  30. use no suffixes; then the file name must be given in full. The search
  31. of the directories in `load-path' goes on as usual in this case, but
  32. it too can be prevented by passing an absolute file name.
  33. The value of `load-path' no longer by default includes nil (meaning to
  34. look in the current default directory). The idea is that `load' should
  35. be used to search the path only for libraries to be found in the standard
  36. places. If you want to override system libraries with your own, place
  37. your own libraries in one special directory and add that directory to the
  38. front of `load-path'.
  39. The function `load' is no longer a command; that is to say, `M-x load'
  40. is no longer allowed. Instead, there are two commands for loading files.
  41. `M-x load-library' is equivalent to the old meaning of `M-x load'.
  42. `M-x load-file' reads a file name with completion and defaulting
  43. and then loads exactly that file, with no searching and no suffixes.
  44. * `edt-emulation-on' starts emulating DEC's EDT editor.
  45. Do `edt-emulation-off' to return Emacs to normal.
  46. * New support for keypads and function keys.
  47. There is now a first attempt at terminal-independent support for
  48. keypad and function keys.
  49. Emacs now defines a standard set of key-names for function and keypad
  50. keys, and provides standard hooks for defining them. Most of the
  51. standard key-names have default definitions built into Emacs; you can
  52. override these in a terminal-independent manner. The default definitions
  53. and the conventions for redefining them are in the file `lisp/keypad.el'.
  54. These keys on the terminal normally work by sending sequences of
  55. characters starting with ESC. The exact sequences used vary from
  56. terminal to terminal. Emacs interprets them in two stages:
  57. in the first stage, terminal-dependent sequences are mapped into
  58. the standard key-names; then second stage maps the standard key-names
  59. into their definitions in a terminal-independent fashion.
  60. The terminal-specific file `term/$TERM.el' now is responsible only for
  61. establishing the mapping from the terminal's escape sequences into
  62. standard key-names. It no longer knows what Emacs commands are
  63. assigned to the standard key-names.
  64. One other change in terminal-specific files: if the value of the TERM
  65. variable contains a hyphen, only the part before the first hyphen is
  66. used in forming the name of the terminal-specific file. Thus, for
  67. terminal type `aaa-48', the file loaded is now `term/aaa.el' rather
  68. than `term/aaa-48.el'.
  69. * New startup command line options.
  70. `-i FILE' or `-insert FILE' in the command line to Emacs tells Emacs to
  71. insert the contents of FILE into the current buffer at that point in
  72. command line processing. This is like using the command M-x insert-file.
  73. `-funcall', `-load', `-user' and `-no-init-file' are new synonyms for
  74. `-f', `-l', `-u' and `-q'.
  75. * Buffer-sorting commands.
  76. Various M-x commands whose names start with `sort-' sort parts of
  77. the region:
  78. sort-lines divides the region into lines and sorts them alphabetically.
  79. sort-pages divides into pages and sorts them alphabetically.
  80. sort-paragraphs divides into paragraphs and sorts them alphabetically.
  81. sort-fields divides into lines and sorts them alphabetically
  82. according to one field in the line.
  83. The numeric argument specifies which field (counting
  84. from field 1 at the beginning of the line). Fields in a line
  85. are separated by whitespace.
  86. sort-numeric-fields
  87. is similar but converts the specified fields to numbers
  88. and sorts them numerically.
  89. sort-columns divides into lines and sorts them according to the contents
  90. of a specified range of columns.
  91. Refer to the self-documentation of these commands for full usage information.
  92. * Changes in various commands.
  93. ** `tags-query-replace' and `tags-search' change.
  94. These functions now display the name of the file being searched at the moment.
  95. ** `occur' output now serves as a menu. `occur-menu' command deleted.
  96. `M-x occur' now allows you to move quickly to any of the occurrences
  97. listed. Select the `*Occur*' buffer that contains the output of `occur',
  98. move point to the occurrence you want, and type C-c C-c.
  99. This will move point to the same occurrence in the buffer that the
  100. occurrences were found in.
  101. The command `occur-menu' is thus obsolete, and has been deleted.
  102. ** Incremental search changes.
  103. Ordinary and regexp incremental searches now have distint default
  104. search strings. Thus, regexp searches recall only previous regexp
  105. searches.
  106. If an incremental search is failing and you ask to repeat it,
  107. it will start again from the beginning of the buffer (or the end,
  108. if it is a backward search).
  109. The search-controlling parameters `isearch-slow-speed' and
  110. `isearch-slow-window-lines' have now been renamed to start with
  111. `search' instead of `isearch'. Now all the parameters' names start
  112. with `search'.
  113. ** Undo changes
  114. The undo command now will mark the buffer as unmodified only when it is
  115. identical to the contents of the visited file.
  116. ** C-M-v in minibuffer.
  117. If while in the minibuffer you request help in a way that uses a
  118. window to display something, then until you exit the minibuffer C-M-v
  119. in the minibuffer window scrolls the window of help.
  120. For example, if you request a list of possible completions, C-M-v can
  121. be used reliably to scroll the completion list.
  122. * Dealing with files.
  123. ** C-x C-v generalized
  124. This command is now allowed even if the current buffer is not visiting
  125. a file. As usual, it kills the current buffer and replaces it with a
  126. newly found file.
  127. ** M-x recover-file improved; auto save file names changed.
  128. M-x recover-file now checks whether the last auto-save file is more
  129. recent than the real visited file before offering to read in the
  130. auto-save file. If the auto-save file is newer, a directory listing
  131. containing the two files is displayed while you are asked whether you
  132. want the auto save file.
  133. Auto save file names now by default have a `#' at the end as well
  134. as at the beginning. This is so that `*.c' in a shell command
  135. will never match auto save files.
  136. On VMS, auto save file names are made by appending `_$' at the front
  137. and `$' at the end.
  138. When you change the visited file name of a buffer, the auto save file
  139. is now renamed to belong to the new visited file name.
  140. You can customize the way auto save file names are made by redefining
  141. the two functions `make-auto-save-file-name' and `auto-save-file-name-p',
  142. both of which are defined in `files.el'.
  143. ** Modifying a buffer whose file is changed on disk is detected instantly.
  144. On systems where clash detection (locking of files being edited) is
  145. implemented, Emacs also checks the first time you modify a buffer
  146. whether the file has changed on disk since it was last visited or saved.
  147. If it has, you are asked to confirm that you want to change the buffer.
  148. ** Backup file changes.
  149. If a backup file cannot be written in the directory of the visited file
  150. due to fascist file protection, a backup file is now written in your home
  151. directory as `~/%backup%~'. Only one such file is made, ever, so only
  152. the most recently made such backup is available.
  153. When backup files are made by copying, the last-modification time of the
  154. original file is now preserved in the backup copy.
  155. ** Dired `g' command.
  156. `g' in Dired mode is equivalent to M-x revert-buffer; it causes the
  157. current contents of the same directory to be read in.
  158. * Changes in major modes.
  159. ** C mode indentation change.
  160. The binding of Linefeed is no longer changed by C mode. It once again
  161. has its normal meaning, which is to insert a newline and then indent
  162. afterward.
  163. The old definition did one additional thing: it reindented the line
  164. before the new newline. This has been removed because it made the
  165. command twice as slow. The only time it was really useful was after the
  166. insertion of an `else', since the fact of starting with `else' may change
  167. the way that line is indented. Now you will have to type TAB again
  168. yourself to reindent the `else' properly.
  169. If the variable `c-tab-always-indent' is set to `nil', the TAB command
  170. in C mode, with no argument, will just insert a tab character if there
  171. is non-whitespace preceding point on the current line. Giving it a
  172. prefix argument will force reindentation of the line (as well as
  173. of the compound statement that begins after point, if any).
  174. ** Telnet mode changes.
  175. The telnet mode special commands have now been assigned to C-c keys.
  176. Most of them are the same as in Shell mode.
  177. ** Picture mode changes.
  178. The special picture-mode commands to specify the direction of cursor
  179. motion after insertion have been moved to C-c keys. The commands to
  180. specify diagonal motion were already C-c keys; they are unchanged.
  181. The keys to specify horizontal or vertical motion are now
  182. C-c < (left), C-c > (right), C-c ^ (up) and C-c . (down).
  183. ** Nroff mode comments.
  184. Comments are now supported in Nroff mode. The standard comment commands
  185. such as M-; and C-x ; know how to insert, align and delete comments
  186. that start with backslash-doublequote.
  187. ** LaTeX mode.
  188. LaTeX mode now exists. Use M-x latex-mode to select this mode, and
  189. M-x plain-text-mode to select the previously existing mode for Plain
  190. TeX. M-x tex-mode attempts to examine the contents of the buffer and
  191. choose between latex-mode and plain-tex-mode accordingly; if the
  192. buffer is empty or it cannot tell, the variable `TeX-default-mode'
  193. controls the choice. Its value should be the symbol for the mode to
  194. be used.
  195. The facilities for running TeX on all or part of the buffer
  196. work with LaTeX as well.
  197. Some new commands available in both modes:
  198. C-c C-l recenter the window showing the TeX output buffer
  199. so most recent line of output can be seen.
  200. C-c C-k kill the TeX subprocess.
  201. C-c C-q show the printer queue.
  202. C-c C-f close a block (appropriate for LaTeX only).
  203. If the current line contains a \begin{...},
  204. this inserts an \end{...} on the following line
  205. and puts point on a blank line between them.
  206. ** Outline mode changes.
  207. Invisible lines in outline mode are now indicated by `...' at the
  208. end of the previous visible line.
  209. The special outline heading motion commands are now all on C-c keys.
  210. A few new ones have been added. Here is a full list:
  211. C-c C-n Move to next visible heading (formerly M-})
  212. C-c C-p Move to previous visible heading (formerly M-{)
  213. C-c C-f Move to next visible heading at the same level.
  214. Thus, if point is on a level-2 heading line,
  215. this command moves to the next visible level-2 heading.
  216. C-c C-b Move to previous visible heading at the same level.
  217. C-c C-u Move up to previous visible heading at a higher level.
  218. The variable `outline-regexp' now controls recognition of heading lines.
  219. Any line whose beginning matches this regexp is a heading line.
  220. The depth in outline structure is determined by the length of
  221. the string that matches.
  222. * Mail reading and sending.
  223. ** mh-e changes.
  224. A new version of mh-e is installed. I do not know how it differs
  225. from the old one; but then, I don't know how to use the old one.
  226. ** Mail mode changes.
  227. The C-c commands of this mode have been rearranged:
  228. C-c s, C-c c, C-c t and C-c b (move point to various header fields)
  229. have been reassigned as C-c C-f C-s, C-c C-f C-c, C-c C-f C-t and C-c
  230. C-f C-b. C-c C-f is for "field".
  231. C-c y, C-c w and C-c q have been changed to C-c C-y, C-c C-w and C-c C-q.
  232. Thus, C-c LETTER is always unassigned.
  233. * Init file changes.
  234. ** Suffixes no longer accepted on `.emacs'.
  235. Emacs will no longer load a file named `.emacs.el' or `emacs.elc'
  236. in place of `.emacs'. This is so that it will take less time to
  237. find `.emacs'. If you want to compile your init file, give it another
  238. name and make `.emacs' a link to the `.elc' file, or make it contain
  239. a call to `load' to load the `.elc' file.
  240. ** `default-profile' renamed to `default', and loaded after `.emacs'.
  241. It used to be the case that the file `default-profile' was loaded if
  242. and only if `.emacs' was not found.
  243. Now the name `default-profile' is not used at all. Instead, a library
  244. named `default' is loaded after the `.emacs' file. `default' is loaded
  245. whether the `.emacs' file exists or not. However, loading of `default'
  246. can be prevented if the `.emacs' file sets `inhibit-default-init' to non-nil.
  247. In fact, you would call the default file `default.el' and probably would
  248. byte-compile it to speed execution.
  249. Note that for most purposes you are better off using a `site-init' library
  250. since that will be loaded before the runnable Emacs is dumped. By using
  251. a `site-init' library, you avoid taking up time each time Emacs is started.
  252. ** inhibit-command-line has been eliminated.
  253. This variable used to exist for .emacs files to set. It has been
  254. eliminated because you can get the same effect by setting
  255. command-line-args to nil and setting inhibit-startup-message to t.
  256. * `apply' is more general.
  257. `apply' now accepts any number of arguments. The first one is a function;
  258. the rest are individual arguments to pass to that function, except for the
  259. last, which is a list of arguments to pass.
  260. Previously, `apply' required exactly two arguments. Its old behavior
  261. follows as a special case of the new definition.
  262. * New code-letter for `interactive'.
  263. (interactive "NFoo: ") is like (interactive "nFoo: ") in reading
  264. a number using the minibuffer to serve as the argument; however,
  265. if a prefix argument was specified, it uses the prefix argument
  266. value as the argument, and does not use the minibuffer at all.
  267. This is used by the `goto-line' and `goto-char' commands.
  268. * Semantics of variables.
  269. ** Built-in per-buffer variables improved.
  270. Several built-in variables which in the past had a different value in
  271. each buffer now behave exactly as if `make-variable-buffer-local' had
  272. been done to them.
  273. These variables are `tab-width', `ctl-arrow', `truncate-lines',
  274. `fill-column', `left-margin', `mode-line-format', `abbrev-mode',
  275. `overwrite-mode', `case-fold-search', `auto-fill-hook',
  276. `selective-display', `selective-display-ellipses'.
  277. To be precise, each variable has a default value which shows through
  278. in most buffers and can be accessed with `default-value' and set with
  279. `set-default'. Setting the variable with `setq' makes the variable
  280. local to the current buffer. Changing the default value has retroactive
  281. effect on all buffers in which the variable is not local.
  282. The variables `default-case-fold-search', etc., are now obsolete.
  283. They now refer to the default value of the variable, which is not
  284. quite the same behavior as before, but it should enable old init files
  285. to continue to work.
  286. ** New per-buffer variables.
  287. The variables `fill-prefix', `comment-column' and `indent-tabs-mode'
  288. are now per-buffer. They work just like `fill-column', etc.
  289. ** New function `setq-default'.
  290. `setq-default' sets the default value of a variable, and uses the
  291. same syntax that `setq' accepts: the variable name is not evaluated
  292. and need not be quoted.
  293. `(setq-default case-fold-search nil)' would make searches case-sensitive
  294. in all buffers that do not have local values for `case-fold-search'.
  295. ** Functions `global-set' and `global-value' deleted.
  296. These functions were never used except by mistake by users expecting
  297. the functionality of `set-default' and `default-value'.
  298. * M-x disassemble.
  299. This command prints the disassembly of a byte-compiled Emacs Lisp function.
  300. Would anyone like to interface this to the debugger?
  301. * New hook `shell-set-directory-error-hook'.
  302. The value of this variable is called, with no arguments, whenever
  303. Shell mode gets an error trying to keep track of directory-setting
  304. commands (such as `cd' and `pushd') used in the shell buffer.
  305. * `insert-buffer-substring' can insert part of the current buffer.
  306. The old restriction that the text being inserted had to come from
  307. a different buffer is now lifted.
  308. When inserting text from the current buffer, the text to be inserted
  309. is determined from the specified bounds before any copying takes place.
  310. * New function `substitute-key-definition'.
  311. This is a new way to replace one command with another command as the
  312. binding of whatever keys may happen to refer to it.
  313. (substitute-key-definition OLDDEF NEWDEF KEYMAP) looks through KEYMAP
  314. for keys defined to run OLDDEF, and rebinds those keys to run NEWDEF
  315. instead.
  316. * New function `documentation-property'.
  317. (documentation-property SYMBOL PROPNAME) is like (get SYMBOL PROPNAME),
  318. except that if the property value is a number `documentation-property'
  319. will take that number (or its absolute value) as a character position
  320. in the DOC file and return the string found there.
  321. (documentation-property VAR 'variable-documentation) is the proper
  322. way for a Lisp program to get the documentation of variable VAR.
  323. * Multiple hooks allowed in certain contexts.
  324. The old hook variables `find-file-hook', `find-file-not-found-hook' and
  325. `write-file-hook' have been replaced.
  326. The replacements are `find-file-hooks', `find-file-not-found-hooks'
  327. and `write-file-hooks'. Each holds a list of functions to be called;
  328. by default, `nil', for no functions. The functions are called in
  329. order of appearance in the list.
  330. In the case if `find-file-hooks', all the functions are executed.
  331. In the case of `find-file-not-found-hooks', if any of the functions
  332. returns non-`nil', the rest of the functions are not called.
  333. In the case of `write-file-hooks', if any of the functions returns
  334. non-`nil', the rest of the functions are not called, and the file is
  335. considered to have been written already; so actual writing in the
  336. usual way is not done.
  337. `find-file-not-found-hooks' and `write-file-hooks' can be used
  338. together to implement editing of files that are not stored as Unix
  339. files: stored in archives, or inside version control systems, or on
  340. other machines running other operating systems and accessible via ftp.
  341. * Disabling commands can print a special message.
  342. A command is disabled by giving it a non-`nil' `disabled' property.
  343. Now, if this property is a string, it is included in the message
  344. printed when the user tries to run the command.
  345. * Display-related changes.
  346. ** `window-point' valid for selected window.
  347. The value returned by `window-point' used to be incorrect when its
  348. argument was the selected window. Now the value is correct.
  349. ** New mode-line control features.
  350. The display of the mode line used to be controlled by a format-string
  351. that was the value of the variable `mode-line-format'.
  352. This variable still exists, but it now allows more general values,
  353. not just strings. Lists, cons cells and symbols are also meaningful.
  354. The mode line contents are created by outputting various mode elements
  355. one after the other. Here are the kinds of objects that can be
  356. used as mode elements, and what they do in the display:
  357. string the contents of the string are output to the mode line,
  358. and %-constructs are replaced by other text.
  359. t or nil ignored; no output results.
  360. symbol the symbol's value is used. If the value is a string,
  361. the string is output verbatim to the mode line
  362. (so %-constructs are not interpreted). Otherwise,
  363. the symbol's value is processed as a mode element.
  364. list (whose first element is a string or list or cons cell)
  365. the elements of the list are treated as as mode elements,
  366. so that the output they generate is concatenated,
  367. list (whose car is a symbol)
  368. if the symbol's value is non-nil, the second element of the
  369. list is treated as a mode element. Otherwise, the third
  370. element (if any) of the list is treated as a mode element.
  371. There is always one mode element to start with, that being the value of
  372. `mode-line-format', but if this value is a list then it leads to several
  373. more mode elements, which can lead to more, and so on.
  374. There is one new %-construct for mode elements that are strings:
  375. `%n' displays ` Narrow' for a buffer that is narrowed, and/or ` Def'
  376. when a keyboard macro is being defined.
  377. The default value of `mode-line-format' refers to several other variables.
  378. These variables are `mode-name', `mode-line-buffer-identification',
  379. `mode-line-process', `global-mode-string' and `minor-mode-alist'.
  380. The first three are local in every buffer in which they are changed from
  381. the default.
  382. mode-name Name of buffer's major mode. Local in every buffer.
  383. mode-line-buffer-identification
  384. Normally the list ("Emacs: %17b"), it is responsible
  385. for displaying text to indicate what buffer is being shown
  386. and what kind of editing it is doing. `Emacs' means
  387. that a file of characters is being edited. Major modes
  388. such as Info and Dired which edit or view other kinds
  389. of data often change this value. This variables becomes
  390. local to the current buffer if it is setq'd.
  391. mode-line-process
  392. Normally nil, this variable is responsible for displaying
  393. information about the process running in the current buffer.
  394. M-x shell-mode and M-x compile alter this variable.
  395. minor-mode-alist
  396. This variable is responsible for displaying text for those
  397. minor modes that are currently enabled. Its value
  398. is a list of elements of the form (VARIABLE STRING),
  399. where STRING is to be displayed if VARIABLE's value
  400. (in the buffer whose mode line is being displayed)
  401. is non-nil. This variable is not made local to particular
  402. buffers, but loading some libraries may add elements to it.
  403. global-mode-string
  404. This variable is used to display the time, if you ask
  405. for that.
  406. The idea of these variables is to eliminate the need for major modes
  407. to alter mode-line-format itself.
  408. ** Deleted function `set-minor-mode'; minor modes must be changed.
  409. The function `set-minor-mode' has been eliminated. The display
  410. of minor mode names in the mode line is now controlled by the
  411. variable `minor-mode-alist'. To specify display of a new minor
  412. mode, it is sufficient to add an element to this list. Once that
  413. is done, you can turn the mode on and off just by setting a variable,
  414. and the display will show its status automatically.
  415. ** New per-buffer variable `selective-display-ellipses'.
  416. If this variable is non-nil, an ellipsis (`...') appears on the screen
  417. at the end of each text line that is followed by invisible text.
  418. If this variable is nil, no ellipses appear. Then there is no sign
  419. on the screen that invisible text is present.
  420. Text is made invisible under the control of the variable
  421. `selective-display'; this is how Outline mode and C-x $ work.
  422. ** New variable `no-redraw-on-reenter'.
  423. If you set this variable non-nil, Emacs will not clear the screen when
  424. you resume it after suspending it. This is for the sake of terminals
  425. with multiple screens of memory, where the termcap entry has been set
  426. up to switch between screens when Emacs is suspended and resumed.
  427. ** New argument to `set-screen-height' or `set-screen-width'.
  428. These functions now take an optional second argument which says
  429. what significance the newly specified height or width has.
  430. If the argument is nil, or absent, it means that Emacs should
  431. believe that the terminal height or width really is as just specified.
  432. If the argument is t, it means Emacs should not believe that the
  433. terminal really is this high or wide, but it should use the
  434. specific height or width as the number of lines or columns to display.
  435. Thus, you could display only 24 lines on a screen known to have 48 lines.
  436. What practical difference is there between using only 24 lines for display
  437. and really believing that the terminal has 24 lines?
  438. 1. The ``real'' height of the terminal says what the terminal command
  439. to move the cursor to the last line will do.
  440. 2. The ``real'' height of the terminal determines how much padding is
  441. needed.
  442. * File-related changes.
  443. ** New parameter `backup-by-copying-when-mismatch'.
  444. If this variable is non-`nil', then when Emacs is about to save a
  445. file, it will create the backup file by copying if that would avoid
  446. changing the file's uid or gid.
  447. The default value of this variable is `nil', because usually it is
  448. useful to have the uid of a file change according to who edited it
  449. last. I recommend thet this variable be left normally `nil' and
  450. changed with a local variables list in those particular files where
  451. the uid needs to be preserved.
  452. ** New parameter `file-precious-flag'.
  453. If this variable is non-`nil', saving the buffer tries to avoid
  454. leaving an incomplete file due to disk full or other I/O errors.
  455. It renames the old file before saving. If saving is successful,
  456. the renamed file is deleted; if saving gets an error, the renamed
  457. file is renamed back to the name you visited.
  458. Backups are always made by copying for such files.
  459. ** `rename-file', `copy-file', `add-name-to-file' and `make-symbolic-link'.
  460. The third argument to these functions used to be `t' or `nil'; `t'
  461. meaning go ahead even if the specified new file name already has a file,
  462. and `nil' meaning to get an error.
  463. Now if the third argument is a number it means to ask the user for
  464. confirmation in this case.
  465. ** New optional argument to `copy-file'.
  466. If `copy-file' receives a non-nil fourth argument, it attempts
  467. to give the new copy the same time-of-last-modification that the
  468. original file has.
  469. ** New function `file-newer-than-file-p'.
  470. (file-newer-than-file-p FILE1 FILE2) returns non-nil if FILE1 has been
  471. modified more recently than FILE2. If FILE1 does not exist, the value
  472. is always nil; otherwise, if FILE2 does not exist, the value is t.
  473. This is meant for use when FILE2 depends on FILE1, to see if changes
  474. in FILE1 make it necessary to recompute FILE2 from it.
  475. ** Changed function `file-exists-p'.
  476. This function is no longer the same as `file-readable-p'.
  477. `file-exists-p' can now return t for a file that exists but which
  478. the fascists won't allow you to read.
  479. ** New function `file-name-sans-versions'.
  480. (file-name-sans-versions NAME) returns a substring of NAME, with any
  481. version numbers or other backup suffixes deleted from the end.
  482. ** New functions for directory names.
  483. Although a directory is really a kind of file, specifying a directory
  484. uses a somewhat different syntax from specifying a file.
  485. In Emacs, a directory name is used as part of a file name.
  486. On Unix, the difference is small: a directory name ends in a slash,
  487. while a file name does not: thus, `/usr/rms/' to name a directory,
  488. while `/usr/rms' names the file which holds that directory.
  489. On VMS, the difference is considerable: `du:[rms.foo]' specifies a
  490. directory, but the name of the file that holds that directory is
  491. `du:[rms]foo.dir'.
  492. There are two new functions for converting between directory names
  493. and file names. `directory-file-name' takes a directory name and
  494. returns the name of the file in which that directory's data is stored.
  495. `file-name-as-directory' takes the name of a file and returns
  496. the corresponding directory name. These always understand Unix file name
  497. syntax; on VMS, they understand VMS syntax as well.
  498. For example, (file-name-as-directory "/usr/rms") returns "/usr/rms/"
  499. and (directory-file-name "/usr/rms/") returns "/usr/rms".
  500. On VMS, (file-name-as-directory "du:[rms]foo.dir") returns "du:[rms.foo]"
  501. and (directory-file-name "du:[rms.foo]") returns "du:[rms]foo.dir".
  502. ** Value of `file-attributes' changed.
  503. The function file-attributes returns a list containing many kinds of
  504. information about a file. Now the list has a tenth element, which is
  505. `t' if deleting the file and creating another file of the same name
  506. would result in a change in the file's group; `nil' if there would
  507. be no change. You can also think of this as comparing the file's group
  508. with the default group for files created in the same directory by you.
  509. ** VMS-only function `file-name-all-versions'.
  510. This function returns a list of all the completions, including version
  511. number, of a specified version-number-less file name. This is like
  512. `file-name-all-completions', except that the latter returns values
  513. that do not include version numbers.
  514. ** `insert-file-contents' on an empty file.
  515. This no longer sets the buffer's "modified" flag.
  516. ** New function (VMS only) `define-logical-name':
  517. (define-logical-name LOGICAL TRANSLATION) defines a VMS logical name
  518. LOGICAL whose translation is TRANSLATION. The new name applies to
  519. the current process only.
  520. ** Deleted variable `ask-about-buffer-names'.
  521. If you want buffer names for files to be generated in a special way,
  522. you must redefine `create-file-buffer'.
  523. * Subprocess-related changes.
  524. ** New function `process-list'.
  525. This function takes no arguments and returns a list of all
  526. of Emacs's asynchronous subprocesses.
  527. ** New function `process-exit-status'.
  528. This function, given a process, process name or buffer as argument,
  529. returns the exit status code or signal number of the process.
  530. If the process has not yet exited or died, this function returns 0.
  531. ** Process output ignores `buffer-read-only'.
  532. Output from a process will go into the process's buffer even if the
  533. buffer is read only.
  534. * New functions `user-uid' and `user-real-uid'.
  535. These functions take no arguments and return, respectively,
  536. the effective uid and the real uid of the Emacs process.
  537. The value in each case is an integer.
  538. News regarding installation:
  539. * Emacs no longer uses floating point arithmetic.
  540. This may make it easier to port to some machines.
  541. * `DOCSTR...' file now called `DOC-...'.
  542. The file of on-line documentation strings, that used to be
  543. `DOCSTR.mm.nn.oo' in this directory, is now called `DOC-mm.nn.oo'.
  544. This is so that it can port to VMS using the standard conventions
  545. for translating filenames for VMS.
  546. This file also now contains the doc strings for variables as
  547. well as functions.
  548. * Macros `XPNTR' and `XSETPNTR'; flag `DATA_SEG_BITS'.
  549. These macros exclusively are used to unpack a pointer from a Lisp_Object
  550. and to insert a pointer into a Lisp_Object. Redefining them may help
  551. port Emacs to machines in which all pointers to data objects have
  552. certain high bits set.
  553. If `DATA_SEG_BITS' is defined, it should be a number which contains
  554. the high bits to be inclusive or'ed with pointers that are unpacked.
  555. * Compilation switch `A_TEXT_OFFSET'.
  556. Define this switch on machines which use the BSD binary format
  557. but count the header of the file as part of the size of the text segment.
  558. * Macros `ARRAY_MARK_FLAG' and `DONT_COPY_FLAG'.
  559. * `HAVE_ALLOCA' prevents assembly of `alloca.s'.
  560. * `SYSTEM_MALLOC' prevents use of GNU `malloc.c'.
  561. SYSTEM_MALLOC, if defined, means use the system's own `malloc' routines
  562. rather than those that come with Emacs.
  563. Use this only if absolutely necessary, because if it is used you do
  564. not get warnings when space is getting low.
  565. * `NO_REMAP' says don't remap data as text.
  566. When Emacs is built, it initializes a large amount of data that will
  567. never be changed again. Normally Emacs attempts to make this part
  568. of the text segment when it is dumped, so that it can be shared.
  569. But this assumes that the data segment starts shortly after the text
  570. segment and that the data segment start can be at a variable place.
  571. On some machines this cannot work, often because the data segment
  572. starts at a fixed place nowhere near the text segment.
  573. For these machines, the clean solution is now to define `NO_REMAP'
  574. in the m- file.
  575. When `NO_REMAP' is defined, the standard system `crt0.o' file is used,
  576. as the problems that usually prevent it from working have to do with
  577. remapping. This means you do not need to alter Emacs's `crt0.c' for
  578. such machines.
  579. * `PNTR_COMPARISON_TYPE'
  580. Pointers that need to be compared for ordering are converted to this type
  581. first. Normally this is `unsigned int'.
  582. * `HAVE_VFORK', `HAVE_DUP2' and `HAVE_GETTIMEOFDAY'.
  583. These flags just say whether certain system calls are available.
  584. For older news, see the file ONEWS.
  585. ----------------------------------------------------------------------
  586. Copyright information:
  587. Copyright (C) 1986 Richard M. Stallman
  588. Permission is granted to anyone to make or distribute verbatim copies
  589. of this document as received, in any medium, provided that the
  590. copyright notice and this permission notice are preserved,
  591. thus giving the recipient permission to redistribute in turn.
  592. Permission is granted to distribute modified versions
  593. of this document, or of portions of it,
  594. under the above conditions, provided also that they
  595. carry prominent notices stating who last changed them.
  596. Local variables:
  597. mode: text
  598. end:
  599. * New macros control compiler switches, linker switches and libraries.
  600. The m- and s- files can now control in a modular fashion the precise
  601. arguments passed to `cc' and `ld'.
  602. LIBS_STANDARD defines the standard C libraries. Default is `-lc'.
  603. LIBS_DEBUG defines the extra libraries to use when debugging. Default `-lg'.
  604. LIBS_SYSTEM can be defined by the s- file to specify extra libraries.
  605. LIBS_MACHINE can be defined by the m- file to specify extra libraries.
  606. LIBS_TERMCAP defines the libraries for Termcap or Terminfo.
  607. It is defined by default in a complicated fashion but the m- or s- file
  608. can override it.
  609. LD_SWITCH_SYSTEM can be defined by the s- file to specify extra `ld' switches.
  610. The default is `-X' on BSD systems except those few that use COFF object files.
  611. LD_SWITCH_MACHINE can be defined by the m- file to specify extra `ld' switches.
  612. C_DEBUG_SWITCH defines the switches to give `cc' when debugging. Default `-g'.
  613. C_OPTIMIZE_SWITCH defines the switches to give `cc' to optimize. Default `-O'.
  614. C_SWITCH_MACHINE can be defined by the m- file to specify extra `cc' switches.