NEWS.18 62.1 KB
 Dave Love committed Oct 03, 1999 1 GNU Emacs NEWS -- history of user-visible changes. 17-Aug-1988  Glenn Morris committed Feb 11, 2007 2   Paul Eggert committed Jan 01, 2018 3 Copyright (C) 1988, 2006-2018 Free Software Foundation, Inc.  Glenn Morris committed Feb 11, 2007 4 5 See the end of the file for license conditions.  Dave Love committed Oct 03, 1999 6   Kim F. Storm committed Jun 04, 2006 7 8 9 This file is about changes in emacs version 18.  Dave Love committed Oct 03, 1999 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117  Changes in version 18.52. * X windows version 10 is supported under system V. * Pop-up menus are now supported with the same Lisp interface in both version 10 and 11 of X windows. * C-x 4 a is a new command to edit a change-log entry in another window. * The emacs client program now allows an option +NNN to specify the line number to go to in the file whose name follows. Thus, emacsclient foo.c +45 bar.c will find the files foo.c' and bar.c', going to line 45 in bar.c'. * Dired allows empty directories to be deleted like files. * When the terminal type is used to find a terminal-specific file to run, Emacs now tries the entire terminal type first. If that doesn't yield a file that exists, the last hyphen and what follows it is stripped. If that doesn't yield a file that exists, the previous hyphen is stripped, and so on until all hyphens are gone. For example, if the terminal type is aaa-48-foo', Emacs will try first term/aaa-48-foo.el', then term/aaa-48.el' and finally term/aaa.el'. Underscores now receive the same treatment as hyphens. * Texinfo features: @defun, etc. texinfo-show-structure. New template commands. texinfo-format-region. * The special "local variable" eval' is now ignored if you are running as root. * New command c-macro-expand' shows the result of C macro expansion in the region. It works using the C preprocessor, so its results are completely accurate. * Errors in trying to auto save now flash error messages for a few seconds. * Killing a buffer now sends SIGHUP to the buffer's process. * New hooks. ** spell-region' now allows you to filter the text before spelling-checking. If the value of spell-filter' is non-nil, it is called, with no arguments, looking at a temporary buffer containing a copy of the text to be checked. It can alter the text freely before the spell program sees it. ** The variable lpr-command' now specifies the command to be used when you use the commands to print text (such as M-x print-buffer). ** Posting netnews now calls the value of news-inews-hook' (if not nil) as a function of no arguments before the actual posting. ** Rmail now calls the value of rmail-show-message-hook' (if not nil) as a function of no arguments, each time a new message is selected. ** kill-emacs' calls the value of kill-emacs-hook' as a function of no args. * New libraries. See the source code of each library for more information. ** icon.el: a major mode for editing programs written in Icon. ** life.el: a simulator for the cellular automaton "life". Load the library and run M-x life. ** doctex.el: a library for converting the Emacs etc/DOC' file of documentation strings into TeX input. ** saveconf.el: a library which records the arrangement of windows and buffers when you exit Emacs, and automatically recreates the same setup the next time you start Emacs. ** uncompress.el: a library that automatically uncompresses files when you visit them. ** c-fill.el: a mode for editing filled comments in C. ** kermit.el: an extended version of shell-mode designed for running kermit. ** spook.el: a library for adding some "distract the NSA" keywords to every message you send. ** hideif.el: a library for hiding parts of a C program based on preprocessor conditionals. ** autoinsert.el: a library to put in some initial text when you visit a nonexistent file. The text used depends on the major mode, and comes from a directory of files created by you. * New programming features. ** The variable window-system-version' now contains the version number of the window system you are using (if appropriate). When using X windows, its value is either 10 or 11. ** (interactive "N") uses the prefix argument if any; otherwise, it reads a number using the minibuffer. ** VMS: there are two new functions vms-system-info' and shrink-to-icon'. The former allows you to get many kinds of system status information. See its self-documentation for full details. The second is used with the window system: it iconifies the Emacs window. ** VMS: the new function define-logical-name' allows you to create job-wide logical names. The old function define-dcl-symbol' has been removed.  Kim F. Storm committed Jun 04, 2006 118 119   Dave Love committed Oct 03, 1999 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174  Changes in version 18.50. * X windows version 11 is supported. Define X11 in config.h if you want X version 11 instead of version 10. * The command M-x gdb runs the GDB debugger as an inferior. It asks for the filename of the executable you want to debug. GDB runs as an inferior with I/O through an Emacs buffer. All the facilities of Shell mode are available. In addition, each time your program stops, and each time you select a new stack frame, the source code is displayed in another window with an arrow added to the line where the program is executing. Special GDB-mode commands include M-s, M-n, M-i, M-u, M-d, and C-c C-f which send the GDB commands step', next', stepi', up', down' and finish'. In any source file, the commands C-x SPC tells GDB to set a breakpoint on the current line. * M-x calendar displays a three-month calendar. * C-u 0 C-x C-s never makes a backup file. This is a way you can explicitly request not to make a backup. * term-setup-hook' is for users only. Emacs never uses this variable for internal purposes, so you can freely set it in your .emacs' file to make Emacs do something special after loading any terminal-specific setup file from lisp/term'. * copy-keymap' now copies recursive submaps. * New overlay-arrow feature. If you set the variable overlay-arrow-string' to a string and overlay-arrow-position' to a marker, that string is displayed on the screen at the position of that marker, hiding whatever text would have appeared there. If that position isn't on the screen, or if the buffer the marker points into isn't displayed, there is no effect. * -batch mode can read from the terminal. It now works to use read-char' to do terminal input in a noninteractive Emacs run. End of file causes Emacs to exit. * Variables data-bytes-used' and data-bytes-free' removed. These variables cannot really work because the 24-bit range of an integer in (most ports of) GNU Emacs is not large enough to hold their values on many systems.  Kim F. Storm committed Jun 04, 2006 175 176   Dave Love committed Oct 03, 1999 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203  Changes in version 18.45, since version 18.41. * C indentation parameter c-continued-brace-offset'. This parameter's value is added to the indentation of any line that is in a continuation context and starts with an open-brace. For example, it applies to the open brace shown here: if (x) { The default value is zero. * Dabbrev expansion (Meta-/) preserves case. When you use Meta-/ to search the buffer for an expansion of an abbreviation, if the expansion found is all lower case except perhaps for its first letter, then the case pattern of the abbreviation is carried over to the expansion that replaces it. * TeX-mode syntax. \ is no longer given "escape character" syntax in TeX mode. It now has the syntax of an ordinary punctuation character. As a result, $...$ and such like are considered to balance each other.  Paul Eggert committed May 20, 2018 204 * Mail-mode automatic Reply-To field.  Dave Love committed Oct 03, 1999 205 206  If the variable mail-default-reply-to' is non-nil', then each time  Paul Eggert committed May 20, 2018 207 you start to compose a message, a Reply-To field is inserted with  Dave Love committed Oct 03, 1999 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 its contents taken from the value of mail-default-reply-to'. * Where is your .emacs file? If you run Emacs under su', so your real and effective uids are different, Emacs uses the home directory associated with the real uid (the name you actually logged in under) to find the .emacs file. Otherwise, Emacs uses the environment variable HOME to find the .emacs file. The .emacs file is not loaded at all if -batch is specified. * Prolog mode is the default for ".pl" files. * File names are not case-sensitive on VMS. On VMS systems, all file names that you specify are converted to upper case. You can use either upper or lower case indiscriminately. * VMS-only function 'define-dcl-symbol'. This is a new name for the function formerly called define-logical-name'.  Kim F. Storm committed Jun 04, 2006 232 233   Dave Love committed Oct 03, 1999 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521  Editing Changes in Emacs 18 * Additional systems and machines are supported. GNU Emacs now runs on Vax VMS. However, many facilities that are normally implemented by running subprocesses do not work yet. This includes listing a directory and sending mail. There are features for running subprocesses but they are incompatible with those on Unix. I hope that some of the VMS users can reimplement these features for VMS (compatibly for the user, if possible). VMS wizards are also asked to work on making the subprocess facilities more upward compatible with those on Unix, and also to rewrite their internals to use the same Lisp objects that are used on Unix to represent processes. In addition, the TI Nu machine running Unix system V, the AT&T 3b, and the Wicat, Masscomp, Integrated Solutions, Alliant, Amdahl uts, Mips, Altos 3068 and Gould Unix systems are now supported. The IBM PC-RT is supported under 4.2, but not yet under system V. The GEC 93 is close to working. The port for the Elxsi is partly merged. See the file MACHINES for full status information and machine-specific installation advice. * Searching is faster. Forward search for a text string, or for a regexp that is equivalent to a text string, is now several times faster. Motion by lines and counting lines is also faster. * Memory usage improvements. It is no longer possible to run out of memory during garbage collection. As a result, running out of memory is never fatal. This is due to a new garbage collection algorithm which compactifies strings in place rather than copying them. Another consequence of the change is a reduction in total memory usage and a slight increase in garbage collection speed. * Display changes. ** Editing above top of screen. When you delete or kill or alter text that reaches to the top of the screen or above it, so that display would start in the middle of a line, Emacs will usually attempt to scroll the text so that display starts at the beginning of a line again. ** Yanking in the minibuffer. The message "Mark Set" is no longer printed when the minibuffer is active. This is convenient with many commands, including C-y, that normally print such a message. ** Cursor appears in last line during y-or-n questions. Questions that want a y' or n' answer now move the cursor to the last line, following the question. * Library loading changes. load' now considers all possible suffixes (.elc', .el' and none) for each directory in load-path' before going on to the next directory. It now accepts an optional fourth argument which, if non-nil, says to use no suffixes; then the file name must be given in full. The search of the directories in load-path' goes on as usual in this case, but it too can be prevented by passing an absolute file name. The value of load-path' no longer by default includes nil (meaning to look in the current default directory). The idea is that load' should be used to search the path only for libraries to be found in the standard places. If you want to override system libraries with your own, place your own libraries in one special directory and add that directory to the front of load-path'. The function load' is no longer a command; that is to say, M-x load' is no longer allowed. Instead, there are two commands for loading files. M-x load-library' is equivalent to the old meaning of M-x load'. M-x load-file' reads a file name with completion and defaulting and then loads exactly that file, with no searching and no suffixes. * Emulation of other editors. ** edt-emulation-on' starts emulating DEC's EDT editor. Do edt-emulation-off' to return Emacs to normal. ** vi-mode' and vip-mode' starts emulating vi. These are two different vi emulations provided by GNU Emacs users. We are interested in feedback as to which emulation is preferable. See the documentation and source code for these functions for more information. ** set-gosmacs-bindings' emulates Gosling Emacs. This command changes many global bindings to resemble those of Gosling Emacs. The previous bindings are saved and can be restored using set-gnu-bindings'. * Emulation of a display terminal. Within Emacs it is now possible to run programs (such as emacs or supdup) which expect to do output to a visual display terminal. See the function terminal-emulator' for more information. * New support for keypads and function keys. There is now a first attempt at terminal-independent support for keypad and function keys. Emacs now defines a standard set of key-names for function and keypad keys, and provides standard hooks for defining them. Most of the standard key-names have default definitions built into Emacs; you can override these in a terminal-independent manner. The default definitions and the conventions for redefining them are in the file lisp/keypad.el'. These keys on the terminal normally work by sending sequences of characters starting with ESC. The exact sequences used vary from terminal to terminal. Emacs interprets them in two stages: in the first stage, terminal-dependent sequences are mapped into the standard key-names; then second stage maps the standard key-names into their definitions in a terminal-independent fashion. The terminal-specific file term/$TERM.el' now is responsible only for establishing the mapping from the terminal's escape sequences into standard key-names. It no longer knows what Emacs commands are assigned to the standard key-names. One other change in terminal-specific files: if the value of the TERM variable contains a hyphen, only the part before the first hyphen is used in forming the name of the terminal-specific file. Thus, for terminal type aaa-48', the file loaded is now term/aaa.el' rather than term/aaa-48.el'. * New startup command line options. -i FILE' or -insert FILE' in the command line to Emacs tells Emacs to insert the contents of FILE into the current buffer at that point in command line processing. This is like using the command M-x insert-file. -funcall', -load', -user' and -no-init-file' are new synonyms for -f', -l', -u' and -q'. -nw' means don't use a window system. If you are using a terminal emulator on the X window system and you want to run Emacs to work through the terminal emulator instead of working directly with the window system, use this switch. * Buffer-sorting commands. Various M-x commands whose names start with sort-' sort parts of the region: sort-lines divides the region into lines and sorts them alphabetically. sort-pages divides into pages and sorts them alphabetically. sort-paragraphs divides into paragraphs and sorts them alphabetically. sort-fields divides into lines and sorts them alphabetically according to one field in the line. The numeric argument specifies which field (counting from field 1 at the beginning of the line). Fields in a line are separated by whitespace. sort-numeric-fields is similar but converts the specified fields to numbers and sorts them numerically. sort-columns divides into lines and sorts them according to the contents of a specified range of columns. Refer to the self-documentation of these commands for full usage information. * Changes in various commands. ** tags-query-replace' and tags-search' change. These functions now display the name of the file being searched at the moment. ** occur' output now serves as a menu. occur-menu' command deleted. M-x occur' now allows you to move quickly to any of the occurrences listed. Select the *Occur*' buffer that contains the output of occur', move point to the occurrence you want, and type C-c C-c. This will move point to the same occurrence in the buffer that the occurrences were found in. The command occur-menu' is thus obsolete, and has been deleted. One way to get a list of matching lines without line numbers is to copy the text to another buffer and use the command keep-lines'. ** Incremental search changes. Ordinary and regexp incremental searches now have distinct default search strings. Thus, regexp searches recall only previous regexp searches. If you exit an incremental search when the search string is empty, the old default search string is kept. The default does not become empty. Reversing the direction of an incremental search with C-s or C-r when the search string is empty now does not get the default search string. It leaves the search string empty. A second C-s or C-r will get the default search string. As a result, you can do a reverse incremental regexp search with C-M-s C-r. If you add a *', ?' or \|' to an incremental search regexp, point will back up if that is appropriate. For example, if you have searched for ab' and add a *', point moves to the first match for ab*', which may be before the match for ab' that was previously found. If an incremental search is failing and you ask to repeat it, it will start again from the beginning of the buffer (or the end, if it is a backward search). The search-controlling parameters isearch-slow-speed' and isearch-slow-window-lines' have now been renamed to start with search' instead of isearch'. Now all the parameters' names start with search'. If search-slow-window-lines' is negative, the slow search window is put at the top of the screen, and the absolute value or the negative number specifies the height of it. ** Undo changes The undo command now will mark the buffer as unmodified only when it is identical to the contents of the visited file. ** C-M-v in minibuffer. If while in the minibuffer you request help in a way that uses a window to display something, then until you exit the minibuffer C-M-v in the minibuffer window scrolls the window of help. For example, if you request a list of possible completions, C-M-v can be used reliably to scroll the completion list. ** M-TAB command. Meta-TAB performs completion on the Emacs Lisp symbol names. The sexp in the buffer before point is compared against all existing nontrivial Lisp symbols and completed as far as is uniquely determined by them. Nontrivial symbols are those with either function definitions, values or properties. If there are multiple possibilities for the very next character, a list of possible completions is displayed. ** Dynamic abbreviation package. The new command Meta-/ expands an abbreviation in the buffer before point by searching the buffer for words that start with the abbreviation. ** Changes in saving kbd macros. The commands write-kbd-macro' and append-kbd-macro' have been deleted. The way to save a keyboard macro is to use the new command insert-kbd-macro', which inserts Lisp code to define the macro as it is currently defined into the buffer before point. Visit a Lisp file such as your Emacs init file ~/.emacs', insert the macro definition (perhaps deleting an old definition for the same macro) and then save the file. ** C-x ' command. The new command C-x ' (expand-abbrev) expands the word before point as an abbrev, even if abbrev-mode is not turned on. ** Sending to inferior Lisp. The command C-M-x in Lisp mode, which sends the current defun to an inferior Lisp process, now works by writing the text into a temporary file and actually sending only a load'-form to load the file. As a result, it avoids the Unix bugs that used to strike when the text was above a certain length. With a prefix argument, this command now makes the inferior Lisp buffer appear on the screen and scrolls it so that the bottom is showing. Two variables inferior-lisp-load-command' and inferior-lisp-prompt', exist to customize these feature for different Lisp implementations. ** C-x p now disabled.  Paul Eggert committed Nov 19, 2011 522 The command C-x p, a nonrecommended command which narrows to the current  Dave Love committed Oct 03, 1999 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 page, is now initially disabled like C-x n. * Dealing with files. ** C-x C-v generalized This command is now allowed even if the current buffer is not visiting a file. As usual, it kills the current buffer and replaces it with a newly found file. ** M-x recover-file improved; auto save file names changed. M-x recover-file now checks whether the last auto-save file is more recent than the real visited file before offering to read in the auto-save file. If the auto-save file is newer, a directory listing containing the two files is displayed while you are asked whether you want the auto save file. Visiting a file also makes this check. If the auto-save file is more recent, a message is printed suggesting that you consider using M-x recover file. Auto save file names now by default have a #' at the end as well as at the beginning. This is so that *.c' in a shell command will never match auto save files. On VMS, auto save file names are made by appending _$' at the front and ' at the end. When you change the visited file name of a buffer, the auto save file is now renamed to belong to the new visited file name. You can customize the way auto save file names are made by redefining the two functions make-auto-save-file-name' and auto-save-file-name-p', both of which are defined in files.el'. ** Modifying a buffer whose file is changed on disk is detected instantly. On systems where clash detection (locking of files being edited) is implemented, Emacs also checks the first time you modify a buffer whether the file has changed on disk since it was last visited or saved. If it has, you are asked to confirm that you want to change the buffer. ** Exiting Emacs offers to save *mail*'. Emacs can now know about buffers that it should offer to save on exit even though they are not visiting files. This is done for any buffer which has a non-nil local value of buffer-offer-save'. By default, Mail mode provides such a local value. ** Backup file changes. If a backup file cannot be written in the directory of the visited file due to fascist file protection, a backup file is now written in your home directory as ~/%backup%~'. Only one such file is made, ever, so only the most recently made such backup is available. When backup files are made by copying, the last-modification time of the original file is now preserved in the backup copy. ** Visiting remote files. On an internet host, you can now visit and save files on any other internet host directly from Emacs with the commands M-x ftp-find-file and M-x ftp-write-file. Specify an argument of the form HOST:FILENAME. Since standard internet FTP is used, the other host may be any kind of machine and is not required to have any special facilities. The first time any one remote host is accessed, you will be asked to give the user name and password for use on that host. FTP is reinvoked each time you ask to use it, but previously specified user names and passwords are remembered automatically. ** Dired g' command. g' in Dired mode is equivalent to M-x revert-buffer; it causes the current contents of the same directory to be read in. * Changes in major modes. ** C mode indentation change. The binding of Linefeed is no longer changed by C mode. It once again has its normal meaning, which is to insert a newline and then indent afterward. The old definition did one additional thing: it reindented the line before the new newline. This has been removed because it made the command twice as slow. The only time it was really useful was after the insertion of an else', since the fact of starting with else' may change the way that line is indented. Now you will have to type TAB again yourself to reindent the else' properly. If the variable c-tab-always-indent' is set to nil', the TAB command in C mode, with no argument, will just insert a tab character if there is non-whitespace preceding point on the current line. Giving it a prefix argument will force reindentation of the line (as well as of the compound statement that begins after point, if any). ** Fortran mode now exists. This mode provides commands for motion and indentation of Fortran code, plus built-in abbrevs for Fortran keywords. For details, see the manual or the on-line documentation of the command fortran-mode'. ** Scribe mode now exists. This mode does something useful for editing files of Scribe input. It is used automatically for files with names ending in ".mss". ** Modula2 and Prolog modes now exist. These modes are for editing programs in the languages of the same names. They can be selected with M-x modula-2-mode and M-x prolog-mode. ** Telnet mode changes. The telnet mode special commands have now been assigned to C-c keys. Most of them are the same as in Shell mode. ** Picture mode changes. The special picture-mode commands to specify the direction of cursor motion after insertion have been moved to C-c keys. The commands to specify diagonal motion were already C-c keys; they are unchanged. The keys to specify horizontal or vertical motion are now C-c < (left), C-c > (right), C-c ^ (up) and C-c . (down). ** Nroff mode comments. Comments are now supported in Nroff mode. The standard comment commands such as M-; and C-x ; know how to insert, align and delete comments that start with backslash-doublequote. ** LaTeX mode. LaTeX mode now exists. Use M-x latex-mode to select this mode, and M-x plain-tex-mode to select the previously existing mode for Plain TeX. M-x tex-mode attempts to examine the contents of the buffer and choose between latex-mode and plain-tex-mode accordingly; if the buffer is empty or it cannot tell, the variable TeX-default-mode' controls the choice. Its value should be the symbol for the mode to be used. The facilities for running TeX on all or part of the buffer work with LaTeX as well. Some new commands available in both modes: C-c C-l recenter the window showing the TeX output buffer so most recent line of output can be seen. C-c C-k kill the TeX subprocess. C-c C-q show the printer queue. C-c C-f close a block (appropriate for LaTeX only). If the current line contains a \begin{...}, this inserts an \end{...} on the following line and puts point on a blank line between them. ** Outline mode changes. Invisible lines in outline mode are now indicated by ...' at the end of the previous visible line. The special outline heading motion commands are now all on C-c keys. A few new ones have been added. Here is a full list: C-c C-n Move to next visible heading (formerly M-}) C-c C-p Move to previous visible heading (formerly M-{) C-c C-f Move to next visible heading at the same level. Thus, if point is on a level-2 heading line, this command moves to the next visible level-2 heading. C-c C-b Move to previous visible heading at the same level. C-c C-u Move up to previous visible heading at a higher level. The variable outline-regexp' now controls recognition of heading lines. Any line whose beginning matches this regexp is a heading line. The depth in outline structure is determined by the length of the string that matches. A line starting with a ^L (formfeed) is now by default considered a header line. * Mail reading and sending. ** MH-E changes. MH-E has been extensively modified and improved since the v17 release. It contains many new features, including commands to: extracted failed messages, kill a draft message, undo changes to a mail folder, monitor delivery of a letter, print multiple messages, page digests backwards, insert signatures, and burst digests. Also, many commands have been made to able to deal with named sequences of messages, instead of single messages. MH-E also has had numerous bugs fixed and commands made to run faster. Furthermore, its keybindings have been changed to be compatible with Rmail and the rest of GNU Emacs. ** Mail mode changes. The C-c commands of mail mode have been rearranged: C-c s, C-c c, C-c t and C-c b (move point to various header fields) 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 C-f C-b. C-c C-f is for "field". 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. Thus, C-c LETTER is always unassigned. ** Rmail C-r command changed to w. The Rmail command to edit the current message is now w'. This change has been made because people frequently type C-r while in Rmail hoping to do a reverse incremental search. That now works. * Rnews changes. ** Caesar rotation added. The function news-caesar-buffer-body performs encryption and decryption of the body of a news message. It defaults to the USENET standard of 13, and accepts any numeric arg between 1 to 25 and -25 to -1. The function is bound to C-c C-r in both news-mode and news-reply-mode. ** rmail-output command added. The C-o command has been bound to rmail-output in news-mode. This allows one to append an article to a file which is in either Unix mail or RMAIL format. ** news-reply-mode changes. The C-c commands of news reply mode have been rearranged and changed, so that C-c LETTER is always unassigned: 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. C-c c, C-c t, and C-c b (move to various mail header fields) have been deleted (they make no sense for posting and replying to USENET). C-c s (move to Subject: header field) has been reassigned as C-c C-f C-s. C-c C-f is for "field". Several additional move to news header field commands have been added. The local news-reply-mode bindings now look like this: C-c C-s news-inews (post the message) C-c C-c news-inews C-c C-f move to a header field (and create it if there isn't): C-c C-f C-n move to Newsgroups: C-c C-f C-s move to Subj: C-c C-f C-f move to Followup-To: C-c C-f C-k move to Keywords: C-c C-f C-d move to Distribution: C-c C-f C-a move to Summary: C-c C-y news-reply-yank-original (insert current message, in NEWS). C-c C-q mail-fill-yanked-message (fill what was yanked). C-c C-r caesar rotate all letters by 13 places in the article's body (rot13). * Existing Emacs usable as a server. Programs such as mailers that invoke "the editor" as an inferior to edit some text can now be told to use an existing Emacs process instead of creating a new editor. To do this, you must have an Emacs process running and capable of doing terminal I/O at the time you want to invoke it. This means that either you are using a window system and give Emacs a separate window or you run the other programs as inferiors of Emacs (such as, using M-x shell). First prepare the existing Emacs process by loading the server' library and executing M-x server-start. (Your .emacs can do this automatically.) Now tell the other programs to use, as "the editor", the Emacs client program (etc/emacsclient, located in the same directory as this file). This can be done by setting the environment variable EDITOR. When another program invokes the emacsclient as "the editor", the client actually transfers the file names to be edited to the existing Emacs, which automatically visits the files. When you are done editing a buffer for a client, do C-x # (server-edit). This marks that buffer as done, and selects the next buffer that the client asked for. When all the buffers requested by a client are marked in this way, Emacs tells the client program to exit, so that the program that invoked "the editor" will resume execution. You can only have one server Emacs at a time, but multiple client programs can put in requests at the same time. The client/server work only on Berkeley Unix, since they use the Berkeley sockets mechanism for their communication.  Kim F. Storm committed Jun 04, 2006 811   Dave Love committed Oct 03, 1999 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122  Changes in Lisp programming in Emacs version 18. * Init file changes. ** Suffixes no longer accepted on .emacs'. Emacs will no longer load a file named .emacs.el' or emacs.elc' in place of .emacs'. This is so that it will take less time to find .emacs'. If you want to compile your init file, give it another name and make .emacs' a link to the .elc' file, or make it contain a call to load' to load the .elc' file. ** default-profile' renamed to default', and loaded after .emacs'. It used to be the case that the file default-profile' was loaded if and only if .emacs' was not found. Now the name default-profile' is not used at all. Instead, a library named default' is loaded after the .emacs' file. default' is loaded whether the .emacs' file exists or not. However, loading of default' can be prevented if the .emacs' file sets inhibit-default-init' to non-nil. In fact, you would call the default file default.el' and probably would byte-compile it to speed execution. Note that for most purposes you are better off using a site-init' library since that will be loaded before the runnable Emacs is dumped. By using a site-init' library, you avoid taking up time each time Emacs is started. ** inhibit-command-line has been eliminated. This variable used to exist for .emacs files to set. It has been eliminated because you can get the same effect by setting command-line-args to nil and setting inhibit-startup-message to t. * apply' is more general. apply' now accepts any number of arguments. The first one is a function; the rest are individual arguments to pass to that function, except for the last, which is a list of arguments to pass. Previously, apply' required exactly two arguments. Its old behavior follows as a special case of the new definition. * New code-letter for interactive'. (interactive "NFoo: ") is like (interactive "nFoo: ") in reading a number using the minibuffer to serve as the argument; however, if a prefix argument was specified, it uses the prefix argument value as the argument, and does not use the minibuffer at all. This is used by the goto-line' and goto-char' commands. * Semantics of variables. ** Built-in per-buffer variables improved. Several built-in variables which in the past had a different value in each buffer now behave exactly as if make-variable-buffer-local' had been done to them. These variables are tab-width', ctl-arrow', truncate-lines', fill-column', left-margin', mode-line-format', abbrev-mode', overwrite-mode', case-fold-search', auto-fill-hook', selective-display', selective-display-ellipses'. To be precise, each variable has a default value which shows through in most buffers and can be accessed with default-value' and set with set-default'. Setting the variable with setq' makes the variable local to the current buffer. Changing the default value has retroactive effect on all buffers in which the variable is not local. The variables default-case-fold-search', etc., are now obsolete. They now refer to the default value of the variable, which is not quite the same behavior as before, but it should enable old init files to continue to work. ** New per-buffer variables. The variables fill-prefix', comment-column' and indent-tabs-mode' are now per-buffer. They work just like fill-column', etc. ** New function setq-default'. setq-default' sets the default value of a variable, and uses the same syntax that setq' accepts: the variable name is not evaluated and need not be quoted. (setq-default case-fold-search nil)' would make searches case-sensitive in all buffers that do not have local values for case-fold-search'. ** Functions global-set' and global-value' deleted. These functions were never used except by mistake by users expecting the functionality of set-default' and default-value'. * Changes in defaulting of major modes. When default-major-mode' is nil', new buffers are supposed to get their major mode from the buffer that is current. However, certain major modes (such as Dired mode, Rmail mode, Rmail Summary mode, and others) are not reasonable to use in this way. Now such modes' names have been given non-nil' mode-class' properties. If the current buffer's mode has such a property, Fundamental mode is used as the default for newly created buffers. * where-is-internal' requires additional arguments. This function now accepts three arguments, two of them required: DEFINITION, the definition to search for; LOCAL-KEYMAP, the keymap to use as the local map when doing the searching, and FIRST-ONLY, which is nonzero to return only the first key found. This function returns a list of keys (strings) whose definitions (in the LOCAL-KEYMAP or the current global map) are DEFINITION. If FIRST-ONLY is non-nil, it returns a single key (string). This function has changed incompatibly in that now two arguments are required when previously only one argument was allowed. To get the old behavior of this function, write (current-local-map)' as the expression for the second argument. The incompatibility is sad, but nil' is a legitimate value for the second argument (it means there is no local keymap), so it cannot also serve as a default meaning to use the current local keymap. * Abbrevs with hooks. When an abbrev defined with a hook is expanded, it now performs the usual replacement of the abbrev with the expansion before running the hook. Previously the abbrev itself was deleted but the expansion was not inserted. * Function scan-buffer' deleted. Use search-forward' or search-backward' in place of scan-buffer'. You will have to rearrange the arguments. * X window interface improvements. ** Detect release of mouse buttons. Button-up events can now be detected. See the file lisp/x-mouse.el' for details. ** New pop-up menu facility. The new function x-popup-menu' pops up a menu (in a X window) and returns an indication of which selection the user made. For more information, see its self-documentation. * M-x disassemble. This command prints the disassembly of a byte-compiled Emacs Lisp function. Would anyone like to interface this to the debugger? * insert-buffer-substring' can insert part of the current buffer. The old restriction that the text being inserted had to come from a different buffer is now lifted. When inserting text from the current buffer, the text to be inserted is determined from the specified bounds before any copying takes place. * New function substitute-key-definition'. This is a new way to replace one command with another command as the binding of whatever keys may happen to refer to it. (substitute-key-definition OLDDEF NEWDEF KEYMAP) looks through KEYMAP for keys defined to run OLDDEF, and rebinds those keys to run NEWDEF instead. * New function insert-char'. Insert a specified character, a specified number of times. * mark-marker' changed. When there is no mark, this now returns a marker that points nowhere, rather than nil'. * ding' accepts argument. When given an argument, the function ding' does not terminate execution of a keyboard macro. Normally, ding' does terminate all macros that are currently executing. * New function minibuffer-depth'. This function returns the current depth in minibuffer activations. The value is zero when the minibuffer is not in use. Values greater than one are possible if the user has entered the minibuffer recursively. * New function documentation-property'. (documentation-property SYMBOL PROPNAME) is like (get SYMBOL PROPNAME), except that if the property value is a number documentation-property' will take that number (or its absolute value) as a character position in the DOC file and return the string found there. (documentation-property VAR 'variable-documentation) is the proper way for a Lisp program to get the documentation of variable VAR. * New documentation-string expansion feature. If a documentation string (for a variable or function) contains text of the form \', it means that all command names specified in \[COMMAND]' construct from that point on should be turned into keys using the value of the variable FOO as the local keymap. Thus, for example, \\[eval-defun] evaluates the defun containing point.' will expand into "ESC C-x evaluates the defun containing point." regardless of the current major mode, because ESC C-x is defined to run eval-defun' in the keymap emacs-lisp-mode-map'. The effect is to show the key for eval-defun' in Emacs Lisp mode regardless of the current major mode. The \<...>' construct applies to all \[...]' constructs that follow it, up to the end of the documentation string or the next \<...>'. Without \<...>', the keys for commands specified in \[...]' are found in the current buffer's local map. The current global keymap is always searched second, whether \<...>' has been used or not. * Multiple hooks allowed in certain contexts. The old hook variables find-file-hook', find-file-not-found-hook' and write-file-hook' have been replaced. The replacements are find-file-hooks', find-file-not-found-hooks' and write-file-hooks'. Each holds a list of functions to be called; by default, nil', for no functions. The functions are called in order of appearance in the list. In the case of find-file-hooks', all the functions are executed. In the case of find-file-not-found-hooks', if any of the functions returns non-nil', the rest of the functions are not called. In the case of write-file-hooks', if any of the functions returns non-nil', the rest of the functions are not called, and the file is considered to have been written already; so actual writing in the usual way is not done. If write-file-hooks' is local to a buffer, it is set to its global value if set-visited-file-name' is called (and thus by C-x C-w as well). find-file-not-found-hooks' and write-file-hooks' can be used together to implement editing of files that are not stored as Unix files: stored in archives, or inside version control systems, or on other machines running other operating systems and accessible via ftp. * New hooks for suspending Emacs. Suspending Emacs runs the hook suspend-hook' before suspending and the hook suspend-resume-hook' if the suspended Emacs is resumed. Running a hook is done by applying the variable's value to no arguments if the variable has a non-nil' value. If suspend-hook' returns non-nil', then suspending is inhibited and so is running the suspend-resume-hook'. The non-nil' value means that the suspend-hook' has done whatever suspending is required. * Disabling commands can print a special message. A command is disabled by giving it a non-nil' disabled' property. Now, if this property is a string, it is included in the message printed when the user tries to run the command. * Emacs can open TCP connections. The function open-network-stream' opens a TCP connection to a specified host and service. Its value is a Lisp object that represents the connection. The object is a kind of "subprocess", and I/O are done like I/O to subprocesses. * Display-related changes. ** New mode-line control features. The display of the mode line used to be controlled by a format-string that was the value of the variable mode-line-format'. This variable still exists, but it now allows more general values, not just strings. Lists, cons cells and symbols are also meaningful. The mode line contents are created by outputting various mode elements one after the other. Here are the kinds of objects that can be used as mode elements, and what they do in the display: string the contents of the string are output to the mode line, and %-constructs are replaced by other text. t or nil ignored; no output results. symbol the symbol's value is used. If the value is a string, the string is output verbatim to the mode line (so %-constructs are not interpreted). Otherwise, the symbol's value is processed as a mode element. list (whose first element is a string or list or cons cell)  Glenn Morris committed Oct 27, 2017 1123  the elements of the list are treated as mode elements,  Dave Love committed Oct 03, 1999 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305  so that the output they generate is concatenated, list (whose car is a symbol) if the symbol's value is non-nil, the second element of the list is treated as a mode element. Otherwise, the third element (if any) of the list is treated as a mode element. cons (whose car is a positive integer) the cdr of the cons is used as a mode element, but the text it produces is padded, if necessary, to have at least the width specified by the integer. cons (whose car is a negative integer) the cdr of the cons is used as a mode element, but the text it produces is truncated, if necessary, to have at most the width specified by the integer. There is always one mode element to start with, that being the value of mode-line-format', but if this value is a list then it leads to several more mode elements, which can lead to more, and so on. There is one new %-construct for mode elements that are strings: %n' displays  Narrow' for a buffer that is narrowed. The default value of mode-line-format' refers to several other variables. These variables are mode-name', mode-line-buffer-identification', mode-line-process', mode-line-modified', global-mode-string' and minor-mode-alist'. The first four are local in every buffer in which they are changed from the default. mode-name Name of buffer's major mode. Local in every buffer. mode-line-buffer-identification Normally the list ("Emacs: %17b"), it is responsible for displaying text to indicate what buffer is being shown and what kind of editing it is doing. Emacs' means that a file of characters is being edited. Major modes such as Info and Dired which edit or view other kinds of data often change this value. This variables becomes local to the current buffer if it is setq'd. mode-line-process Normally nil, this variable is responsible for displaying information about the process running in the current buffer. M-x shell-mode and M-x compile alter this variable. mode-line-modified This variable is responsible for displaying the indication of whether the current buffer is modified or read-only. By default its value is ("--%*%*-")'. minor-mode-alist This variable is responsible for displaying text for those minor modes that are currently enabled. Its value is a list of elements of the form (VARIABLE STRING), where STRING is to be displayed if VARIABLE's value (in the buffer whose mode line is being displayed) is non-nil. This variable is not made local to particular buffers, but loading some libraries may add elements to it. global-mode-string This variable is used to display the time, if you ask for that. The idea of these variables is to eliminate the need for major modes to alter mode-line-format itself. ** window-point' valid for selected window. The value returned by window-point' used to be incorrect when its argument was the selected window. Now the value is correct. ** Window configurations may be saved as Lisp objects. The function current-window-configuration' returns a special type of Lisp object that represents the current layout of windows: the sizes and positions of windows, which buffers appear in them, and which parts of the buffers appear on the screen. The function set-window-configuration' takes one argument, which must be a window configuration object, and restores that configuration. ** New hook temp-output-buffer-show-hook'. This hook allows you to control how help buffers are displayed. Whenever with-output-to-temp-buffer' has executed its body and wants to display the temp buffer, if this variable is bound and non-nil' then its value is called with one argument, the temp buffer. The hook function is solely responsible for displaying the buffer. The standard manner of display--making the buffer appear in a window--is used only if there is no hook function. ** New function minibuffer-window'. This function returns the window used (sometimes) for displaying the minibuffer. It can be used even when the minibuffer is not active. ** New feature to next-window'. If the optional second argument is neither nil' nor t', the minibuffer window is omitted from consideration even when active; if the starting window was the last non-minibuffer window, the value will be the first non-minibuffer window. ** New variable minibuffer-scroll-window'. When this variable is non-nil', the command scroll-other-window' uses it as the window to be scrolled. Displays of completion-lists set this variable to the window containing the display. ** New argument to sit-for'. A non-nil second argument to sit-for' means do not redisplay; just wait for the specified time or until input is available. ** Deleted function set-minor-mode'; minor modes must be changed. The function set-minor-mode' has been eliminated. The display of minor mode names in the mode line is now controlled by the variable minor-mode-alist'. To specify display of a new minor mode, it is sufficient to add an element to this list. Once that is done, you can turn the mode on and off just by setting a variable, and the display will show its status automatically. ** New variable cursor-in-echo-area'. If this variable is non-nil, the screen cursor appears on the last line of the screen, at the end of the text displayed there. Binding this variable to t is useful at times when reading single characters of input with read-char'. ** New per-buffer variable selective-display-ellipses'. If this variable is non-nil, an ellipsis (...') appears on the screen at the end of each text line that is followed by invisible text. If this variable is nil, no ellipses appear. Then there is no sign on the screen that invisible text is present. Text is made invisible under the control of the variable selective-display'; this is how Outline mode and C-x work. ** New variable no-redraw-on-reenter'. If you set this variable non-nil, Emacs will not clear the screen when you resume it after suspending it. This is for the sake of terminals with multiple screens of memory, where the termcap entry has been set up to switch between screens when Emacs is suspended and resumed. ** New argument to set-screen-height' or set-screen-width'. These functions now take an optional second argument which says what significance the newly specified height or width has. If the argument is nil, or absent, it means that Emacs should believe that the terminal height or width really is as just specified. If the argument is t, it means Emacs should not believe that the terminal really is this high or wide, but it should use the specific height or width as the number of lines or columns to display. Thus, you could display only 24 lines on a screen known to have 48 lines. What practical difference is there between using only 24 lines for display and really believing that the terminal has 24 lines? 1. The real'' height of the terminal says what the terminal command to move the cursor to the last line will do. 2. The real'' height of the terminal determines how much padding is needed. * File-related changes. ** New parameter backup-by-copying-when-mismatch'. If this variable is non-nil', then when Emacs is about to save a file, it will create the backup file by copying if that would avoid changing the file's uid or gid. The default value of this variable is nil', because usually it is useful to have the uid of a file change according to who edited it  Paul Eggert committed Nov 19, 2011 1306 last. I recommend that this variable be left normally nil' and  Dave Love committed Oct 03, 1999 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 changed with a local variables list in those particular files where the uid needs to be preserved. ** New parameter file-precious-flag'. If this variable is non-nil', saving the buffer tries to avoid leaving an incomplete file due to disk full or other I/O errors. It renames the old file before saving. If saving is successful, the renamed file is deleted; if saving gets an error, the renamed file is renamed back to the name you visited. Backups are always made by copying for such files. ** New variable buffer-offer-save'. If the value of this variable is non-nil' in a buffer then exiting Emacs will offer to save the buffer (if it is modified and nonempty) even if the buffer is not visiting a file. This variable is automatically made local to the current buffer whenever it is set. ** rename-file', copy-file', add-name-to-file' and make-symbolic-link'. The third argument to these functions used to be t' or nil'; t' meaning go ahead even if the specified new file name already has a file, and nil' meaning to get an error. Now if the third argument is a number it means to ask the user for confirmation in this case. ** New optional argument to copy-file'. If copy-file' receives a non-nil fourth argument, it attempts to give the new copy the same time-of-last-modification that the original file has. ** New function file-newer-than-file-p'. (file-newer-than-file-p FILE1 FILE2) returns non-nil if FILE1 has been modified more recently than FILE2. If FILE1 does not exist, the value is always nil; otherwise, if FILE2 does not exist, the value is t. This is meant for use when FILE2 depends on FILE1, to see if changes in FILE1 make it necessary to recompute FILE2 from it. ** Changed function file-exists-p'. This function is no longer the same as file-readable-p'. file-exists-p' can now return t for a file that exists but which the fascists won't allow you to read. ** New function file-locked-p'. This function receives a file name as argument and returns nil' if the file is not locked, t' if locked by this Emacs, or a string giving the name of the user who has locked it. ** New function file-name-sans-versions'. (file-name-sans-versions NAME) returns a substring of NAME, with any version numbers or other backup suffixes deleted from the end. ** New functions for directory names. Although a directory is really a kind of file, specifying a directory uses a somewhat different syntax from specifying a file. In Emacs, a directory name is used as part of a file name. On Unix, the difference is small: a directory name ends in a slash, while a file name does not: thus, /usr/rms/' to name a directory, while /usr/rms' names the file which holds that directory. On VMS, the difference is considerable: du:[rms.foo]' specifies a directory, but the name of the file that holds that directory is du:[rms]foo.dir'. There are two new functions for converting between directory names and file names. directory-file-name' takes a directory name and returns the name of the file in which that directory's data is stored. file-name-as-directory' takes the name of a file and returns the corresponding directory name. These always understand Unix file name syntax; on VMS, they understand VMS syntax as well. For example, (file-name-as-directory "/usr/rms") returns "/usr/rms/" and (directory-file-name "/usr/rms/") returns "/usr/rms". On VMS, (file-name-as-directory "du:[rms]foo.dir") returns "du:[rms.foo]" and (directory-file-name "du:[rms.foo]") returns "du:[rms]foo.dir". ** Value of file-attributes' changed. The function file-attributes returns a list containing many kinds of information about a file. Now the list has eleven elements. The tenth element is t' if deleting the file and creating another file of the same name would result in a change in the file's group; nil' if there would be no change. You can also think of this as comparing the file's group with the default group for files created in the same directory by you. The eleventh element is the inode number of the file. ** VMS-only function file-name-all-versions'. This function returns a list of all the completions, including version number, of a specified version-number-less file name. This is like file-name-all-completions', except that the latter returns values that do not include version numbers. ** VMS-only variable vms-stmlf-recfm'. On a VMS system, if this variable is non-nil, Emacs will give newly created files the record format stmlf'. This is necessary for files that must contain lines of arbitrary length, such as compiled Emacs Lisp. When writing a new version of an existing file, Emacs always keeps the same record format as the previous version; so this variable has no effect. This variable has no effect on Unix systems. ** insert-file-contents' on an empty file. This no longer sets the buffer's "modified" flag. ** New function (VMS only) define-logical-name': (define-logical-name LOGICAL TRANSLATION) defines a VMS logical name LOGICAL whose translation is TRANSLATION. The new name applies to the current process only. ** Deleted variable ask-about-buffer-names'. If you want buffer names for files to be generated in a special way, you must redefine create-file-buffer'. * Subprocess-related changes. ** New function process-list'. This function takes no arguments and returns a list of all of Emacs's asynchronous subprocesses. ** New function process-exit-status'. This function, given a process, process name or buffer as argument, returns the exit status code or signal number of the process. If the process has not yet exited or died, this function returns 0. ** Process output ignores buffer-read-only'. Output from a process will go into the process's buffer even if the buffer is read only. ** Switching buffers in filter functions and sentinels. Emacs no longer saves and restore the current buffer around calling the filter and sentinel functions, so these functions can now permanently alter the selected buffer in a straightforward manner. ** Specifying environment variables for subprocesses. When a subprocess is started with start-process' or call-process', the value of the variable process-environment' is taken to specify the environment variables to give the subprocess. The value should be a list of strings, each of the form "VAR=VALUE". process-environment' is initialized when Emacs starts up based on Emacs's environment. ** New variable process-connection-type'. If this variable is nil', when a subprocess is created, Emacs uses a pipe rather than a pty to communicate with it. Normally this variable is t', telling Emacs to use a pty if ptys are supported and one is available. ** New function waiting-for-user-input-p'. This function, given a subprocess as argument, returns t' if that subprocess appears to be waiting for input sent from Emacs, or nil' otherwise. ** New hook shell-set-directory-error-hook'. The value of this variable is called, with no arguments, whenever Shell mode gets an error trying to keep track of directory-setting commands (such as cd' and pushd') used in the shell buffer. * New functions user-uid' and user-real-uid'. These functions take no arguments and return, respectively, the effective uid and the real uid of the Emacs process. The value in each case is an integer. * New variable print-escape-newlines' controls string printing. If this variable is non-nil', then when a Lisp string is printed by the Lisp printing function prin1' or print', newline characters are printed as \n' rather than as a literal newline. * New function sysnetunam' on HPUX. This function takes two arguments, a network address PATH and a login string LOGIN, and executes the system call netunam'. It returns t' if the call succeeds, otherwise nil'. News regarding installation: * Many s-...' file names changed. Many s-...' files have been renamed. All periods in such names, except the ones just before the final h', have been changed to hyphens. Thus, s-bsd4.2.h' has been renamed to s-bsd4-2.h'. This is so a Unix distribution can be moved mechanically to VMS. * DOCSTR...' file now called DOC-...'. The file of on-line documentation strings, that used to be DOCSTR.mm.nn.oo' in this directory, is now called DOC-mm.nn.oo'. This is so that it can port to VMS using the standard conventions for translating filenames for VMS. This file also now contains the doc strings for variables as well as functions. * Emacs no longer uses floating point arithmetic. This may make it easier to port to some machines. * Macros XPNTR' and XSETPNTR'; flag DATA_SEG_BITS'. These macros exclusively are used to unpack a pointer from a Lisp_Object and to insert a pointer into a Lisp_Object. Redefining them may help port Emacs to machines in which all pointers to data objects have certain high bits set. If DATA_SEG_BITS' is defined, it should be a number which contains the high bits to be inclusive or'ed with pointers that are unpacked. * New flag HAVE_X_MENU'. Define this flag in config.h' in addition to HAVE_X_WINDOWS' to enable use of the Emacs interface to X Menus. On some operating systems, the rest of the X interface works properly but X Menus do not work; hence this separate flag. See the file src/xmenu.c' for more information. * Macros ARRAY_MARK_FLAG' and DONT_COPY_FLAG'. * HAVE_ALLOCA' prevents assembly of alloca.s'. * SYSTEM_MALLOC' prevents use of GNU malloc.c'. SYSTEM_MALLOC, if defined, means use the system's own malloc' routines rather than those that come with Emacs. Use this only if absolutely necessary, because if it is used you do not get warnings when space is getting low. * New flags to control unexec. See the file unexec.c' for a long comment on the compilation switches that suffice to make it work on many machines. * PNTR_COMPARISON_TYPE' Pointers that need to be compared for ordering are converted to this type first. Normally this is unsigned int'. * HAVE_VFORK', HAVE_DUP2' and HAVE_GETTIMEOFDAY'. These flags just say whether certain system calls are available. * New macros control compiler switches, linker switches and libraries. The m- and s- files can now control in a modular fashion the precise arguments passed to cc' and ld'. LIBS_STANDARD defines the standard C libraries. Default is -lc'. LIBS_DEBUG defines the extra libraries to use when debugging. Default -lg'. LIBS_SYSTEM can be defined by the s- file to specify extra libraries. LIBS_MACHINE can be defined by the m- file to specify extra libraries. LIBS_TERMCAP defines the libraries for Termcap or Terminfo. It is defined by default in a complicated fashion but the m- or s- file can override it. LD_SWITCH_SYSTEM can be defined by the s- file to specify extra ld' switches. The default is -X' on BSD systems except those few that use COFF object files. LD_SWITCH_MACHINE can be defined by the m- file to specify extra ld' switches. C_DEBUG_SWITCH defines the switches to give cc' when debugging. Default -g'. C_OPTIMIZE_SWITCH defines the switches to give cc' to optimize. Default -O'. C_SWITCH_MACHINE can be defined by the m- file to specify extra cc' switches.  Kim F. Storm committed Jun 04, 2006 1601 1602   Dave Love committed Oct 03, 1999 1603 ----------------------------------------------------------------------  Glenn Morris committed Feb 11, 2007 1604 This file is part of GNU Emacs.  Dave Love committed Oct 03, 1999 1605   Glenn Morris committed May 15, 2008 1606 GNU Emacs is free software: you can redistribute it and/or modify  Glenn Morris committed Feb 11, 2007 1607 it under the terms of the GNU General Public License as published by  Glenn Morris committed May 15, 2008 1608 1609 the Free Software Foundation, either version 3 of the License, or (at your option) any later version.  Glenn Morris committed Feb 11, 2007 1610 1611 1612 1613 1614  GNU Emacs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.  Dave Love committed Oct 03, 1999 1615   Glenn Morris committed Feb 11, 2007 1616 You should have received a copy of the GNU General Public License  Paul Eggert committed Sep 13, 2017 1617 along with GNU Emacs. If not, see .  Dave Love committed Oct 03, 1999 1618 1619 1620 1621 1622  Local variables: mode: text end: