1 -*- coding: utf-8; mode: text; -*-
5 This branch implements support for opening multiple, different tty
6 devices and simultaneous X and tty frames from a single Emacs session.
9 Emacs is notoriously slow at startup, so most people use another
10 editor or emacsclient for quick editing jobs from the console.
11 Unfortunately, emacsclient was very awkward to use, because it did not
12 support opening a new Emacs frame on the current virtual tty.
13 Now, with multi-tty support, it can do that. (Emacsclient starts up
16 Some Gnus users (including me) run Gnus in an X frame in its own Emacs
17 instance, which they typically leave running for weeks. It would be
18 nice if they could connect to this instance from a remote ssh session
19 and check their messages without opening a remote X frame or resorting
25 I'm Károly Lőrentey. My address: lorentey@elte.hu.
27 Comments, bug reports, suggestions and patches are welcome; send them
28 to multi-tty@lists.fnord.hu.
30 The following is a (sadly incomplete) list of people who have
31 contributed to the project by testing, submitting patches, bug
32 reports, and suggestions. Thanks!
34 Bernard Adrian <bernadrian@free.fr>
35 ARISAWA Akihiro <ari@mbf.ocn.ne.jp>
36 Vincent Bernat <bernat@luffy.cx>
37 Han Boetes <han@mijncomputer.nl>
38 Francisco Borges <borges@let.rug.nl>
39 Damien Cassou <damien.cassou@laposte.net>
40 Robert J. Chassell <bob@rattlesnake.com>
41 Romain Francoise <romain@orebokech.com>
42 Ami Fischman <ami@fischman.org>
43 Friedrich Delgado Friedrichs <friedel@nomaden.org>
44 IRIE Tetsuya <irie@t.email.ne.jp>
45 Yoshiaki Kasahara <kasahara@nc.kyushu-u.ac.jp>
46 Bas Kok <nekkobassu@yahoo.com>
47 Jurej Kubelka <Juraj.Kubelka@email.cz>
48 David Lichteblau <david@lichteblau.com>
49 mace <mace@kirjakaapeli.lib.hel.fi>
50 Xavier Mallard <zedek@gnu-rox.org>
51 Istvan Marko <mi-mtty@kismala.com>
52 Ted Morse <morse@ciholas.com>
53 Gergely Nagy <algernon@debian.org>
54 Dan Nicolaescu <dann@ics.uci.edu>
55 Kalle Olavi Niemitalo <kon@iki.fi>
56 Mark Plaksin <happy@mcplaksin.org>
57 Frank Ruell <stoerte@dreamwarrior.net>
58 Tom Schutzer-Weissmann <trmsw@yahoo.co.uk>
59 Joakim Verona <joakim@verona.se>
60 Dan Waber <dwaber@logolalia.com>
63 Richard Stallman was kind enough to review an earlier version of my
70 The multi-tty mailing list (discussion & bug reports):
72 Address: multi-tty@lists.fnord.hu
73 Signup: http://lists.fnord.hu/mailman/listinfo/multi-tty
74 Archive: http://news.gmane.org/gmane.emacs.multi-tty/
76 Commit notifications (read-only):
78 Address: multi-tty-commits@lists.fnord.hu
79 Signup: http://lists.fnord.hu/mailman/listinfo/multi-tty-commits
85 The branch is now very stable and almost full-featured. All of the
86 major problems have been fixed, only a few minor issues remain. (It
87 still needs to be ported to Windows/Mac/DOS, though.) Both multiple
88 tty device support and simultaneous X and tty frame support works
89 fine. Emacsclient has been extended to support opening new tty and X
90 frames. It has been changed to open new Emacs frames by default.
92 The multi-tty branch has been scheduled for inclusion in the next
93 major release of Emacs (version 23). I expect the merge into the
94 development trunk to occur sometime during next year (2006), after the
95 merge of the Unicode branch.
97 Tested on GNU/Linux, Solaris 8, FreeBSD and OpenBSD. Please let me
98 know if you succeed or fail to use it on other platforms---I'll have a
99 few tricky test cases for you.
103 * GTK support. If you compile your Emacs with the GTK
104 toolkit, some functionality of multi-tty will be lost. In
105 particular, you will not be able to work on multiple X
106 displays at once. Current releases of GTK have limitations
107 and bugs that prevent full-blown multi-display support in
108 Emacs. (GTK crashes when Emacs tries to disconnect from an
109 X server.) Use the Lucid toolkit if you want to see a
110 complete feature set.
112 * The single-kboard mode.
114 If your multi-tty Emacs session seems to be frozen, you
115 probably have a recursive editing session or a pending
116 minibuffer prompt (which is a kind of recursive editing) on
117 another display. To unfreeze your session, switch to that
118 display and complete the recursive edit, for example by
119 pressing C-] (`abort-recursive-edit').
121 I am sorry to say that currently there is no way to break
122 out of this "single-kboard mode" from a frozen display. If
123 you are unable to switch to the display that locks the
124 others (for example because it is on a remote computer),
125 then you can use emacsclient to break out of all recursive
128 emacsclient -e '(top-level)'
130 Note that this (perhaps) unintuitive behaviour is by design.
131 Single-kboard mode is required because of an intrinsic Emacs
132 limitation that is very hard to eliminate. (This limitation
133 is related to the single-threaded nature of Emacs.)
135 I plan to implement better user notification and support for
136 breaking out of single-kboard mode from locked displays.
138 * Mac, Windows and DOS support is broken, doesn't even
139 compile. Multiple display support will probably not provide
140 new Emacs features on these systems, but the multi-tty
141 branch changed a few low-level interfaces, and the
142 system-dependent source files need to be adapted
143 accordingly. The changes are mostly trivial, so almost
144 anyone can help, if only by compiling the branch and
145 reporting the compiler errors.
148 HOW TO GET THE BRANCH
149 ---------------------
151 The branch uses Bazaar 1 (http://bazaar.canonical.com) for version control.
153 Retrieving the latest version of the branch:
155 baz register-archive -f http://aszt.inf.elte.hu/~lorentey/mirror/arch/2004
156 baz get lorentey@elte.hu--2004/emacs--multi-tty <directory>
158 This incantation uses an archive mirror that is hosted on a
159 high-bandwidth site. Please note that on average there is a two-hour
160 delay for commits to arrive on this mirror. My primary mirror is on the
161 low-bandwidth http://lorentey.hu/ site:
163 baz register-archive -f http://lorentey.hu/arch/2004/
164 baz get lorentey@elte.hu--2004/emacs--multi-tty <directory>
166 This is "instantly" updated, but very slow from outside Hungary.
167 (By "instantly" I mean as soon as I connect the notebook I work on to
168 a network. It could take days.)
170 The Arch supermirror provides mirroring services for all public Arch
171 repositories. We have a mirror there, too, if you prefer.
173 baz register-archive -f http://mirrors.sourcecontrol.net/lorentey%40elte.hu--2004
174 baz get lorentey@elte.hu--2004/emacs--multi-tty <directory>
176 My GPG key id is 0FB27A3F; it is available from
177 hkp://wwwkeys.eu.pgp.net/, or from my homepage at
178 http://lorentey.hu/rolam/gpg.html)
180 Don't worry if the above checkout takes a few minutes to complete;
181 once you have a source tree, updating it to the latest revision will
182 be _much_ faster. Use the following command for the update:
186 You can find more information about Bazaar on
187 http://bazaar.canonical.com/. It's a distributed source control
188 system that is somewhat less broken than competing projects.
190 If you don't have Bazaar, the branch has a homepage from which you can
191 download conventional patches against Emacs CVS HEAD:
193 http://lorentey.hu/project/emacs.html
195 I suggest you use Bazaar whenever feasible.
201 If you run Debian, or a distribution based on Debian, you are welcome
202 to use our binary packages; put these lines in your /etc/apt/sources.list:
205 deb http://aszt.inf.elte.hu/~lorentey/mirror/apt unstable multi-tty
206 deb-src http://aszt.inf.elte.hu/~lorentey/mirror/apt unstable multi-tty
208 Note that these packages are intended solely to provide an easy way to
209 test the new multi-tty features. They are not to be taken as Emacs
210 releases, and it's a mistake to expect robust operation or any kind of
211 timely support for them. Do not install them, unless you'd like to
212 have your editor crash on you.
218 The multi-tty branch is compiled the same way as Emacs itself:
220 make maintainer-clean # (If you have compiled Emacs before)
222 ./configure --without-gtk <your favourite options>
226 If you have strange compilation errors, they may be caused by old
227 *.elc files that are left over from an earlier bootstrap. The `make
228 maintainer-clean' target deletes them, so it is a good idea to run
229 that before reporting a bug. (Emacs requires a clean recompilation
230 after certain kinds of source code changes.)
235 To test the multi-tty branch, start up the Emacs server with the
241 and then (from a shell prompt on another terminal) start emacsclient
243 emacsclient -t /optional/file/names... (for a tty frame)
244 emacsclient /optional/file/names... (for an X frame)
246 (Make sure both emacs and emacsclient are multi-tty versions.)
247 You'll hopefully have two fully working, independent frames on
248 separate terminals. The new frame is closed automatically when you
249 finish editing the specified files (C-x #), but delete-frame (C-x 5 0)
250 also works. Of course, you can create frames on more than two tty
253 Creating new frames on the same tty with C-x 5 2 (make-frame-command)
254 works, and behaves the same way as in previous Emacs versions. If you
255 exit emacs, all terminals should be restored to their previous states.
257 This is work in progress, and probably full of bugs. It is a good
258 idea to run emacs from gdb, so that you'll have a live instance to
259 debug if something goes wrong. Please send me your bug reports on our
260 mailing list: multi-tty@lists.fnord.hu
265 I think the best way to use the new Emacs is to have it running inside
266 a disconnected GNU screen session, and always use emacsclient for
267 normal work. One advantage of this is that not a single keystroke of
268 your work will be lost if the display device that you are using
269 crashes, or the network connection times out, or whatever. (I had an
270 extremely unstable X server for some time while I was developing these
271 patches, and running Emacs this way has saved me a number of M-x
272 recover-session invocations.)
274 I use the following two bash scripts to handle my Emacs sessions:
276 -------------------------------------------------------connect-emacs--
278 # Usage: connect-emacs <name> <args>...
280 # Connects to the Emacs instance called NAME. Starts up the instance
281 # if it is not already running. The rest of the arguments are passed
287 if [ -z "$name" ]; then
288 echo "Usage: connect_emacs <name> <args>..." >&2
291 preload-emacs "$name" wait
292 /usr/bin/emacsclient.emacs-multi-tty -s "$name" "$@"
293 ----------------------------------------------------------------------
295 -------------------------------------------------------preload-emacs--
297 # Usage: preload-emacs <name> [<waitp>]
299 # Preloads the Emacs instance called NAME in a detached screen
300 # session. Does nothing if the instance is already running. If WAITP
301 # is non-empty, the function waits until the server starts up and
302 # creates its socket; otherwise it returns immediately.
306 screendir="/var/run/screen/S-$USER"
307 serverdir="/tmp/emacs$UID"
308 emacs=/usr/bin/emacs-multi-tty # Or wherever you installed your multi-tty Emacs
310 if [ -z "$name" ]; then
311 echo "Usage: preload_emacs <name> [<waitp>]" >&2
315 if [ ! -e "$screendir"/*."$name" ]; then
316 if [ -e "$serverdir/$name" ]; then
317 # Delete leftover socket (for the wait option)
318 rm "$serverdir/$name"
320 screen -dmS "$name" "$emacs" -nw --eval "(setq server-name \"$name\")" -f server-start
322 if [ ! -z "$waitp" ]; then
323 while [ ! -e "$serverdir/$name" ]; do sleep 0.1; done
325 ----------------------------------------------------------------------
327 I have the following in my profile to have two instances automatically
328 preloaded for editing and email:
333 It is useful to set up short aliases for connect-emacs. I use the
336 alias edit="connect-emacs editor"
338 alias et="connect-emacs editor -t"
339 alias gnus="connect-emacs gnus"
351 For the NEWS file: (Needs much, much work)
353 ** Support for multiple terminal devices and simultaneous graphical
354 and tty frames has been added. You can test for the presence of
355 this feature in your Lisp code by testing for the `multi-tty'
358 *** The `window-system' variable has been made frame-local. The new
359 `initial-window-system' variable contains the `window-system'
360 value for the first frame.
362 *** You can specify a terminal device (`tty' parameter) and a terminal
363 type (`tty-type' parameter) to `make-terminal-frame'.
365 *** The new function `make-frame-on-tty' allows you to create a new
366 frame on another tty device interactively.
368 *** The function `make-frame-on-display' now works during a tty
369 session, and `make-frame-on-tty' works during a graphical session.
371 *** Emacsclient has been extended to support opening a new terminal
372 frame. Its behaviour has been changed to open a new Emacs frame by
373 default. Use the -c option to get the old behavior of opening
374 files in the currently selected Emacs frame.
376 *** C-z now invokes `suspend-frame', C-x C-c now invokes
377 `save-buffers-kill-terminal'.
379 *** New functions: frame-tty-name, frame-tty-type, delete-tty,
380 suspend-tty, resume-tty, terminal-id, terminal-parameters,
381 terminal-parameter, set-terminal-parameter,
382 modify-terminal-parameters, environment, let-environment
384 *** New variables: local-key-translation-map, local-function-key-map
386 *** The `keyboard-translate-table' variable and the terminal and
387 keyboard coding systems have been made terminal-local.
389 *** In addition to the global key-translation-map and
390 function-key-map, Emacs has terminal-local
391 local-key-translation-map and local-function-key-map variables,
392 and uses them instead of the global keymaps to set up translations
393 and function key sequences relevant to a specific terminal device.
395 *** talk.el has been extended for multiple tty support.
399 (The rest of this file consists of my development notes and as such it
400 is probably not very interesting for anyone else.)
405 ** emacsclient -t on the console does not work after su:
409 *ERROR*: Could not open file: /dev/tty1
411 The tty can be opened as /dev/tty by emacsclient, but not by Emacs.
412 This seems to be a serious problem. Currently my only idea is to
413 bring back the ugly pty proxy hack from the initial versions of
414 multi-tty. Suggestions would be appreciated.
416 ** Understand how `quit_throw_to_read_char' works, and fix any bugs
419 ** See if getcjmp can be eliminated somehow. Why does Emacs allow
420 asynchronous input processing while it's reading input anyway?
422 ** `delete-frame' events are handled by `special-event-map'
423 immediately when read by `read_char'. This is fine but it prevents
424 higher-level keymaps from binding that event to get notified of the
427 Sometimes it would be useful for Lisp code to be notified of frame
428 deletions after they have happened, usually because they want to
429 clean up after the deleted frame. Not all frame-local states can
430 be stored as a frame parameter. For example,
431 `display-splash-screen' uses `recursive-edit' with a special keymap
432 override to create its buffer---and it leads to all kinds of
433 nastiness if Emacs stays in this recursive edit mode after the
434 frame containing the splash screen is deleted. Basically, the
435 splash-screen implementation wants to throw out of the recursive
436 edit when the frame is deleted; however, it is not legal to throw
437 from `delete-frame-functions' because `delete-frame' must not fail.
438 (Introducing `delete-frame-after-functions' would not help either
439 because `delete-frame' may not fail at that time either.)
441 Currently `fancy-splash-screens' installs a
442 `delete-frame-functions' hook that sets up a timer to exit the
443 recursive edit. This is an adequate solution, but it would perhaps
444 be better to have something like a `frame-deleted' event that could
445 be bound in the normal way.
447 ** Trouble: `setenv' doesn't actually set environment variables in the
448 Emacs process. This defeats the purpose of the elaborate
449 `server-with-environment' magic around the `tgetent' call in
452 ** (Possibly) create hooks in struct device for creating frames on a
453 specific terminal, and eliminate the hackish terminal-related frame
454 parameters (display, tty, tty-type).
459 ** Decide whether to keep the C implementation of terminal parameters,
460 or revert to the previous, purely Lisp code. It turned out that
461 local environments do not need terminal parameters after all.
463 ** Move Fsend_string_to_terminal to term.c, and declare get_named_tty
464 as static, removing it from dispextern.h.
465 Move fatal to emacs.c and declare it somewhere.
467 ** Search for `suspend-emacs' references and replace them with
468 `suspend-frame', if necessary. Ditto for `save-buffers-kill-emacs'
469 vs. `save-buffers-kill-display'.
471 ** Emacs crashes when a tty frame is resized so that there is no space
472 for all its windows. (Tom Schutzer-Weissmann)
474 ** Report GTK multi-display problems to GTK maintainers. For extra
477 Currently you can not connect to new X displays when you compile
478 Emacs with GTK support. If you want to play around with GTK
479 multidisplay (and don't mind core dumps), you can edit src/config.h
480 and define HAVE_GTK_MULTIDISPLAY there by hand.
482 Update: Han reports that GTK+ version 2.8.9 almost gets display
483 disconnects right. GTK will probably be fully fixed by the time
484 multi-tty gets into the trunk.
486 ** Audit `face-valid-attribute-values' usage in customize and
487 elsewhere. Its return value depends on the current window system.
488 Replace static initializers using it with runtime functions. For
489 example, custom's buttons are broken on non-initial device types.
491 ** Possibly turn off the double C-g feature when there is an X frame.
492 C.f. (emacs)Emergency Escape.
494 ** frames-on-display-list should also accept frames.
496 ** Consider the `tty-type' frame parameter and the `display-tty-type'
497 function. They serve the exact same purpose. I think it may be
498 a good idea to eliminate one of them, preferably `tty-type'.
500 ** The handling of lisp/term/*.el, and frame creation in general, is a
501 big, big mess. How come the terminal-specific file is loaded by
502 tty-create-frame-with-faces? I don't think it is necessary to load
503 these files for each frame; once per terminal should be enough.
504 Update: lisp/term/*.el is not loaded repeatedly anymore, but
505 faces.el still needs to be cleaned up.
507 ** Fix frame-set-background-mode in this branch. It was recently
508 changed in CVS, and frame.el in multi-tty has not yet been adapted
509 for the changes. (It needs to look at
510 default-frame-background-mode.) (Update: maybe it is fixed now;
511 needs testing.) (Note that the byte compiler has this to say about
514 term/rxvt.el:309:17:Warning: assignment to free variable
515 `default-frame-background-mode'
517 ** I think `(set-)terminal-local-value' and the terminal parameter
518 mechanism should be integrated into a single framework.
520 (Update: `(set-)terminal-local-value' is now eliminated, but the
521 terminal-local variables should still be accessible as terminal
522 parameters. This also applies to `display-name' and similar
525 ** Add the following hooks: after-delete-frame-hook (for server.el,
526 instead of delete-frame-functions),
527 after-delete-terminal-functions, after-create-terminal-functions.
529 ** BULK RENAME: The `display-' prefix of new Lisp-level functions
530 conflicts with stuff like `display-time-mode'. Use `device-'
531 or `terminal-' instead. I think I prefer `terminal-'.
533 It turns out that most of the offending Lisp functions were defined
534 in the trunk. Therefore, compatibility aliases should be defined
535 for the following names:
537 display-color-cells terminal-color-cells
538 display-color-p terminal-color-p
539 display-graphic-p terminal-graphic-p
540 display-grayscale-p terminal-grayscale-p
541 display-images-p terminal-images-p
542 display-mm-height terminal-mm-height
543 display-mm-width terminal-mm-width
544 display-mouse-p terminal-mouse-p
545 display-multi-font-p terminal-multi-font-p
546 display-multi-frame-p terminal-multi-frame-p
547 display-pixel-height terminal-pixel-height
548 display-pixel-width terminal-pixel-width
549 display-pixels-per-inch terminal-pixels-per-inch
550 display-planes terminal-planes
551 display-popup-menus-p terminal-popup-menus-p
552 display-save-under terminal-save-under
553 display-screens terminal-screens
554 display-supports-face-attributes-p terminal-supports-face-attributes-p
555 display-visual-class terminal-visual-class
556 framep-on-display framep-on-terminal
557 frames-on-display-list frames-on-terminal-list
559 The following functions were introduced in the multi-tty branch, and
560 were renamed without aliases:
562 delete-display delete-terminal
563 display-controlling-tty-p controlling-tty-p
564 display-list terminal-list
565 display-live-p terminal-live-p
566 display-name terminal-name
567 display-tty-type tty-type
568 frame-display frame-terminal
569 selected-display selected-terminal
571 ** The single-keyboard mode of MULTI_KBOARD is extremely confusing
572 sometimes; Emacs does not respond to stimuli from other keyboards.
573 At least a beep or a message would be important, if the single-mode
574 is still required to prevent interference. (Reported by Dan
577 Update: selecting a region with the mouse enables single_kboard
578 under X. This is very confusing.
580 Update: After discussions with Richard Stallman, this will be
581 resolved by having locked displays warn the user to wait, and
582 introducing a complex protocol to remotely bail out of
583 single-kboard mode by pressing C-g.
585 Update: Warning the user is not trivial to implement, as Emacs has
586 only one echo area, shared by all frames. Ideally the warning
587 should not be displayed on the display that is locking the others.
588 Perhaps the high probability of user confusion caused by
589 single_kboard mode deserves a special case in the display code.
590 Alternatively, it might be good enough to signal single_kboard mode
591 by changing the modelines or some other frame-local display element
592 on the locked out displays.
594 Update: In fact struct kboard does have an echo_string slot.
596 ** The session management module is prone to crashes when the X
597 connection is closed and then later I try to connect to a new X
600 #0 0xb7ebc806 in SmcGetIceConnection () from /usr/X11R6/lib/libSM.so.6
601 #1 0x080e6641 in x_session_check_input (bufp=0xbf86c9c0) at xsmfns.c:144
602 #2 0x080d3bbc in XTread_socket (device=0xa722ff8, expected=1, hold_quit=0xbf86ca90) at xterm.c:7037
603 #3 0x080fa404 in read_avail_input (expected=1) at keyboard.c:6696
604 #4 0x080fa4ca in handle_async_input () at keyboard.c:6900
605 #5 0x080d51fa in x_term_init (display_name=162628899, xrm_option=0x0, resource_name=0x857068c "emacs") at xterm.c:10622
606 #6 0x080d920e in x_display_info_for_name (name=162628899) at xfns.c:3975
607 #7 0x080d92f9 in check_x_display_info (object=1) at xfns.c:274
608 #8 0x080d97b8 in Fx_create_frame (parms=151221485) at xfns.c:3016
609 #9 0x0815bf72 in Ffuncall (nargs=2, args=0xbf86ceec) at eval.c:2851
611 I installed a workaround to prevent this. The X session manager is
612 only contacted when the very first display in the Emacs session is
613 an X display. Also, x_delete_display() on this display aborts
614 session management, and XTread_socket only calls
615 x_session_check_input when it is called for the display that the
616 session was opened on. While this does not really fix the bug, it
617 makes it much less frequent, because session manager support will
618 not normally be enabled when Emacs can survive the shutdown of the
621 See if xsmfns.c should be updated.
623 ** Hunt down display-related functions in frame.el and extend them all
624 to accept display ids.
626 ** rif->flush_display_optional (NULL) calls should be replaced by a
629 ** The set-locale-environment hack (adding the DISPLAY option) should
630 be replaced with a clean design.
632 ** standard-display-table should be display-local.
633 standard-display-european should be display-local.
635 ** With iswitchb-default-method set to 'always-frame, only frames on
636 the current display should be considered. This might involve
637 extending `get-buffer-window'.
639 ** Have a look at Vlocale_coding_system. Seems like it would be a
640 tedious job to localize it, although most references use it for
641 interfacing with libc and are therefore OK with the global
644 Exceptions found so far: x-select-text and
645 x-cut-buffer-or-selection-value.
647 ** Have a look at fatal_error_hook.
649 ** Have a look at set_frame_matrix_frame.
651 ** Check if we got term-setup-hook right.
653 ** I think tip_frame should be display-local.
655 ** Check display reference count handling in x_create_tip_frame.
657 ** make-frame does not correctly handle extra parameters in its
660 (frame-parameter (make-frame (list (cons 'foobar 42))) 'foobar)
663 (This is likely an error in the CVS trunk.)
665 ** Dan Nicolaescu suggests that -nw should be added as an alias for -t
666 in emacsclient. Good idea. (Alas, implementing this is not
667 trivial, getopt_long does not seem to support two-letter ``short''
668 options. Patches are welcome.)
670 ** Mark Plaksin suggests that emacsclient should accept the same
671 X-related command-line arguments as Emacs. Most of the X-related
672 argument-handling is done in Lisp, so this should be quite easy to
675 ** Gergely Nagy suggests that C-x # should only kill the current
676 frame, not any other emacsclient frame that may have the same file
677 opened for editing. I think I agree with him.
679 ** Very strange bug: visible-bell does not work on secondary
680 terminals in xterm and konsole. The screen does flicker a bit,
681 but it's so quick it isn't noticable.
683 (Update: This is probably some problem with padding or whatnot on
684 the secondary terminals.)
686 ** Move baud_rate to struct display.
688 ** Implement support for starting an interactive Emacs session without
689 an initial frame. (The user would connect to it and open frames
690 later, with emacsclient.)
692 ** Fix Mac support (I can't do this entirely myself). Note that the
693 current state of Mac-specific source files in the multi-tty tree
694 are not useful; before starting work on Mac support, revert to
695 pristine, pre-multi-tty versions.
697 ** Fix W32 support (I can't do this entirely myself). Note that the
698 current state of W32-specific source files in the multi-tty tree
699 are not useful; before starting work on W32 support, revert to
700 pristine, pre-multi-tty versions.
702 ** Fix DOS support (I can't do this entirely myself). Note that the
703 current state of DOS-specific source files in the multi-tty tree
704 are not useful; before starting work on DOS support, revert to
705 pristine, pre-multi-tty versions.
707 ** Do a grep on XXX and ?? for more issues.
709 ** flow-ctrl.el must be updated.
711 ** Fix stuff_char for multi-tty. Doesn't seem to be of high priority.
716 (ex-TODO items with explanations.)
718 -- Introduce a new struct for terminal devices.
720 (Done, see struct tty_output. The list of members is not yet
723 -- Change the bootstrap procedure to initialize tty_list.
725 (Done, but needs review.)
727 -- Change make-terminal-frame to support specifying another tty.
729 (Done, new frame parameters: `tty' and `tty-type'.)
731 -- Implement support for reading from multiple terminals.
733 (Done, read_avail_input tries to read from each terminal, until one
734 succeeds. MULTI_KBOARD is not used. Secondary terminals don't send
737 (Update: They do, now.)
739 (Update2: After enabling X, they don't.)
741 -- other-frame should cycle through the frames on the `current'
744 (Done, by trivially modifiying next_frame and prev_frame.)
746 -- Support different terminal sizes.
750 -- Make sure terminal resizes are handled gracefully. (Could be
753 (Done. We don't get automatic SIGWINCH for additional ttys,
756 -- Extend emacsclient to automatically open a new tty when it connects
759 (Done. It's an ugly hack, needs more work.)
761 -- Redisplay must refresh the topmost frame on *all* terminals, not
762 just the initial terminal.
764 (Done, but introduced an ugly redisplay problems. Ugh.)
766 -- Fix redisplay problems.
768 (Done; it turned out that the entire Wcm structure must be moved
769 inside tty_output. Why didn't I catch this earlier?)
771 -- Provide a way for emacsclient to tell Emacs that the tty has been
774 (Done, simply forward the SIGWINCH signal.)
776 -- Each keypress should automatically select the frame corresponding
777 to the terminal that it was coming from. This means that Emacs
778 must know from which terminal the last keyboard event came from.
780 (Done, it was quite simple, the input event system already
781 supported multiple frames.)
783 -- Fix SIGIO issue with secondary terminals.
785 (Done, emacsclient signals Emacs after writing to the proxy pseudo
786 terminal. Note that this means that multi-tty does not work with
789 (Update: This is bullshit. There is a read_input_waiting function,
790 extend that somehow.)
792 (Update of update: The first update was not right either, extending
793 read_input_waiting was not necessary. Secondary ttys do seem to
794 send signals on input.)
796 (Update^3: Not any more.)
798 -- Make make-terminal-frame look up the `tty' and `tty-type' frame
799 parameters from the currently selected terminal before the global
804 -- Put all cached terminal escape sequences into struct tty_output.
805 Currently, they are still stored in global variables, so we don't
806 really support multiple terminal types.
808 (Done. It was not fun.)
810 -- Implement sane error handling after initialization. (Currently
811 emacs exits if you specify a bad terminal type.) The helpful error
812 messages must still be provided when Emacs starts.
816 -- Implement terminal deletion, i.e., deleting local frames, closing
817 the tty device and restoring its previous state without exiting
820 (Done, but at the moment only called when an error happens during
821 initialization. There is a memory corruption error around this
822 somewhere.) (Update: now it is fully enabled.)
824 -- Implement automatic deletion of terminals when the last frame on
825 that terminal is closed.
829 -- Restore tty screen after closing the terminal.
831 (Done, we do the same as Emacs 21.2 for all terminals.)
833 -- 'TERM=dumb src/emacs' does not restore the terminal state.
837 -- C-g should work on secondary terminals.
839 (Done, but the binding is not configurable.)
841 -- Deal with SIGHUP in Emacs and in emacsclient. (After this, the
842 server-frames may be removed from server.el.)
844 (Done, nothing to do. It seems that Emacs does not receive SIGHUP
845 from secondary ttys, which is actually a good thing.) (Update: I
846 think it would be a bad idea to remove server-frames.)
848 -- Change emacsclient/server.el to support the -t argument better,
849 i.e. automatically close the socket when the frame is closed.
851 (Seems to be working OK.)
853 -- Fix mysterious memory corruption error with tty deletion. To
854 trigger it, try the following shell command:
856 while true; do TERM=no-such-terminal-definition emacsclient -h; done
858 Emacs usually dumps core after a few dozen iterations. (The bug
859 seems to be related to the xfreeing or bzeroing of
860 tty_output.Wcm. Maybe there are outside references to struct Wcm?
861 Why were these vars collected into a struct before multi-tty
864 (Done. Whew. It turned out that the problem had nothing to do
865 with hypothetical external references to Wcm, or any other
866 tty_output component; it was simply that delete_tty closed the
867 filehandles of secondary ttys twice, resulting in fclose doubly
868 freeing memory. Utterly trivial matter. I love the C's memory
869 management, it puts hair on your chest.)
871 -- Support raw secondary terminals. (Note that SIGIO works only on
872 the controlling terminal.) Hint: extend read_input_waiting for
873 multiple ttys and hopefully this will be fixed.
875 (Done, it seems to have been working already for some time. It
876 seems F_SETOWN does work, after all. Not sure what made it fail
877 earlier, but it seems to be fixed (there were several changes
878 around request_sigio, maybe one of them did it).
879 read_input_waiting is only used in sys_select, don't change
880 it.) (Update: After adding X support, it's broken again.)
881 (Update^2: No it isn't.) :-)
883 -- Find out why does Emacs abort when it wants to close its
884 controlling tty. Hint: chan_process[] array. Hey, maybe
885 noninterrupt-IO would work, too? Update: no, there is no process
888 (Done. Added add/delete_keyboard_wait_descriptor to
889 term_init/delete_tty. The hint was right, in a way.)
891 -- Issue with SIGIO: it needs to be disabled during redisplay. See if
892 fcntl kernel behaviour could be emulated by emacsclient.
894 (Done. Simply disabled the SIGIO emulation hack in emacsclient.)
895 (Update: it was added back.) (Update^2: and removed again.)
897 -- server.el: There are issues with saving files in buffers of closed
898 clients. Try editing a file with emacsclient -f, and (without
899 saving it) do a delete-frame. The frame is closed without
900 question, and a surprising confirmation prompt appears in another
903 (Done. delete-frame now asks for confirmation if it still has
904 pending buffers, and modified buffers don't seem to be deleted.)
906 -- emacsclient.el, server.el: Handle eval or file open errors when
911 -- Make parts of struct tty_output accessible from Lisp. The device
912 name and the type is sufficient.
914 (Done, see frame-tty-name and frame-tty-type.)
916 -- Export delete_tty to the Lisp environment, for emacsclient.
918 (Done, see delete-tty.)
920 -- Get rid of the accessor macros in termchar.h, or define macros for
925 -- Move device-specific parameters (like costs) commonly used by
926 device backends to a common, device-dependent structure.
928 (Done. See struct display_method in termhooks.h.)
932 (Done. Well, it seems to be working.)
934 -- Allow simultaneous X and tty frames. (Handling input could be
935 tricky. Or maybe not.)
937 (Done. Allowed, that is. It is currently extremely unstable, to
938 the point of being unusable. The rif variable causes constant
939 core dumps. Handling input is indeed tricky.)
941 -- Rewrite multi-tty input in terms of MULTI_KBOARD.
943 (Done. In fact, there was no need to rewrite anything, I just
944 added a kboard member to tty_display_info, and initialized the
945 frame's kboard from there.)
947 -- Fix rif issue with X-tty combo sessions. IMHO the best thing to do
948 is to get rid of that global variable (and use the value value in
949 display_method, which is guaranteed to be correct).
951 (Done, did exactly that. Core dumps during combo sessions became
952 much rarer. In fact, I have not yet met a single one.)
954 -- Add multi-tty support to talk.el.
958 -- Clean up the source of emacsclient. It is a mess.
960 (Done, eliminated stupid proxy-pty kludge.)
962 -- Fix faces on tty frames during X-tty combo sessions. There is an
963 init_frame_faces call in init_sys_modes, see if there is a problem
966 (Done, there was a stupid mistake in
967 Ftty_supports_face_attributes_p. Colors are broken, though.)
969 -- C-x 5 2, C-x 5 o, C-x 5 0 on an emacsclient frame unexpectedly
970 exits emacsclient. This is a result of trying to be clever with
971 delete-frame-functions.
973 (Fixed, added delete-tty-after-functions, and changed server.el to
976 -- Something with (maybe) multi-keyboard support broke function keys
977 and arrows on ttys during X+tty combo sessions. Debug this.
979 (I can't reproduce it, maybe the terminal type was wrong.)
981 -- Fix input from raw ttys (again).
983 (Now it seems to work all right.)
985 -- During an X-tty combo session, a (message "Hello") from a tty frame
986 goes to the X frame. Fix this.
988 (Done. There was a safeguard against writing to the initial
989 terminal frame during bootstrap which prevented echo_area_display
990 from working correctly on a tty frame during a combo session.)
992 -- If there are no frames on its controlling terminal, Emacs should
993 exit if the user presses C-c there.
995 (Done, as far as possible. See the SIGTERM comment in
996 interrupt_signal on why this seems to be impossible to solve this
999 -- During an X session, Emacs seems to read from stdin. Also, Emacs
1000 fails to start without a controlling tty.
1002 (Fixed by replacing the troublesome termcap display with a dummy
1003 bootstrap display during bootstrap.
1005 -- Do tty output through struct display, like graphical display
1010 -- Define an output_initial value for output_method for the initial
1011 frame that is dumped with Emacs. Checking for this frame (e.g. in
1012 cmd_error_internal) is ugly.
1014 (Done, breaking interactive temacs.)
1016 -- The command `emacsclient -t -e '(delete-frame)'' fails to exit.
1020 -- frame-creation-function should always create a frame that is on the
1021 same display as the selected frame. Maybe frame-creation-function
1022 should simply be removed and make-frame changed to do the right
1025 (Done, with a nice hack. frame-creation-function is now frame-local.)
1027 -- Fix C-g on raw ttys.
1029 (Done. I disabled the interrupt/quit keys on all secondary
1030 terminals, so Emacs sees C-g as normal input. This looks like an
1031 overkill, because emacsclient has extra code to pass SIGINT to
1032 Emacs, so C-g should remain the interrupt/quit key on emacsclient
1033 frames. See the next entry why implementing this distinction would
1036 -- Make sure C-g goes to the right frame with ttys. This is hard, as
1037 SIGINT doesn't have a tty parameter. :-(
1039 (Done, the previous change fixes this as a pleasant side effect.)
1041 -- I have seen a case when Emacs with multiple ttys fell into a loop
1042 eating 100% of CPU time. Strace showed this loop:
1045 kill(30284, SIGIO) = 0
1046 --- SIGIO (I/O possible) @ 0 (0) ---
1047 ioctl(6, FIONREAD, [0]) = -1 EIO (Input/output error)
1048 ioctl(5, FIONREAD, [0]) = -1 EIO (Input/output error)
1049 ioctl(0, FIONREAD, [0]) = 0
1050 sigreturn() = ? (mask now [])
1051 gettimeofday({1072842297, 747760}, NULL) = 0
1052 gettimeofday({1072842297, 747806}, NULL) = 0
1053 select(9, [0 3 5 6], NULL, NULL, {0, 0}) = 2 (in [5 6], left {0, 0})
1054 select(9, [0 3 5 6], NULL, NULL, {0, 0}) = 2 (in [5 6], left {0, 0})
1055 gettimeofday({1072842297, 748245}, NULL) = 0
1057 I have seen something similar with a single X frame, but have not
1058 been able to reproduce it for debugging.
1060 Update: This may have been caused by checking for nread != 0
1061 instead of nread > 0 after calling read_socket_hook in
1064 (Fixed. This was caused by unconditionally including stdin in
1065 input_wait_mask in init_process. The select call in
1066 wait_reading_process_input always returned immediately, indicating
1067 that there is pending input from stdin, which nobody read.
1069 Note that the above strace output seems to be an unrelated but
1070 similar bug. I think that is now fixed.)
1072 -- Exiting Emacs while there are emacsclient frames doesn't restore the
1073 ttys to their default states.
1075 (This seems to be fixed by some previous change.)
1077 -- Allow opening an X session after -nw.
1081 -- Fix color handling during tty+X combo sessions. (It seems that tty
1082 sessions automatically convert the face colors to terminal colors
1083 when the face is loaded. This conversion must happen instead on
1084 the fly in write_glyphs, which might be problematic, as color
1085 approximation is currently done in lisp (term/tty-colors.el).)
1086 (Update: hm, colors seem to work fine if I start emacs with -nw and
1087 then create an X frame. Maybe it's just a small buglet somewhere.)
1089 (Seems to be fixed. The problem was in startup.el, it did not
1090 initialize tty colors when the initial window system was
1093 -- emacs -nw --eval '(y-or-n-p "Foobar")' segfaults. (Reported by
1096 (Fixed, there was a keyboard initialization problem.)
1098 -- Fix interactive use of temacs. There are face-related SEGVs, most
1099 likely because of changes in realize_default_face, realize_face.
1103 -- Don't exit Emacs when the last X connection fails during a
1104 multi-display session.
1108 -- Dan Nicolaescu noticed that starting emacsclient on the same
1109 terminal device that is the controlling tty of the Emacs process
1110 gives unexpected results.
1114 -- Istvan Marko reported that Emacs hang on ttys if it was started
1115 from a shell script.
1117 (Fixed. There was a bug in the multi-tty version of
1118 narrow_foreground_group. tcsetpgrp blocks if it is called from a
1119 process that is not in the same process group as the tty.)
1121 -- emacsclient -t from an Emacs term buffer does not work, complains
1122 about face problems. This can even lock up Emacs (if the recursive
1123 frame sets single_kboard). Update: the face problems are caused by
1124 bugs in term.el, not in multi-tty. The lockup is caused by
1125 single_kboard mode, and is not easily resolvable. The best thing to
1126 do is to simply refuse to create a tty frame of type `eterm'.
1128 (Fixed, changed emacsclient to check for TERM=eterm. The face
1129 complaints seem to be caused by bugs in term.el; they are not
1130 related to multi-tty.)
1132 -- Find out the best way to support suspending Emacs with multiple
1133 ttys. My guess: disable it on the controlling tty, but from other
1134 ttys pass it on to emacsclient somehow. (It is (I hope) trivial to
1135 extend emacsclient to handle suspend/resume. A `kill -STOP' almost
1138 (Done. I needed to play with signal handling and the server
1139 protocol a bit to make emacsclient behave as a normal UNIX program
1140 wrt foreground/background process groups.)
1142 -- There is a flicker during the startup of `emacs -nw'; it's as if
1143 the terminal is initialized, reset and then initialialized again.
1144 Debug this. (Hint: narrow_foreground_group is called twice during
1149 -- Robert Chassell has found serious copy-paste bugs with the
1150 multi-tty branch. There seem to be redisplay bugs while copying
1151 from X to a terminal frame. Copying accented characters do not
1154 (Patch-124 should fix this, by changing the interprogram-*-function
1155 variables to be frame-local, as suggested by Mark Plaksin
1156 (thanks!). I think that the redisplay bugs are in fact not bugs,
1157 but delays caused by single_kboard --> perhaps MULTI_KBOARD should
1160 -- frame-creation-function was removed, which might be a bad idea.
1161 Think up a compatible solution.
1163 (It was an internal interface that may be changed when necessary.)
1165 -- Change Lisp code not to (getenv "TERM"); use the `tty-type' frame
1166 parameter or the frame-tty-type function instead. (M-x tags-search
1167 "TERM" helps with this.) Update: Actually, all getenv invocations
1168 should be checked for multi-tty compatibility, and an interface
1169 must be implemented to get the remote client's environment.
1171 (Done. Only getenv calls in lisp/term/*.el were changed; other
1172 calls should be mostly left as they are.)
1174 -- Add an elaborate mechanism for display-local variables. (There are
1175 already a few of these; search for `terminal-local' in the Elisp
1178 (Not needed. Display-local variables could be emulated by
1179 frame-local variables.)
1181 -- Emacs assumes that all terminal frames have the same locale
1182 settings as Emacs itself. This may lead to bogus results in a
1183 multi-locale setup. (E.g., while logging in from a remote client
1184 with a different locale.)
1185 (Update after new bugreport by Friedrich Delgado Friedrichs:
1186 (at least) the structs terminal_coding and keyboard_coding in
1187 coding.c must be moved to struct display, and the Lisp interface
1188 [set-]keyboard-coding-system must be adapted for the change.)
1190 (Fixed. Emacs now uses the locale settings as seen by the
1191 emacsclient process for server tty frames.)
1192 (Update: Not really; Vlocale_coding_system is still global.)
1194 -- Make `struct display' accessible to Lisp programs. Accessor functions:
1196 (displayp OBJECT): Returns t if OBJECT is a display.
1197 => Implemented as display-live-p.
1199 (display-list): Returns list of currently active displays.
1202 (selected-display): Returns the display object of the selected frame.
1203 => Not strictly necessary, but implemented anyway.
1205 (frame-display FRAME): Returns the display object of FRAME.
1208 (display-frames DISPLAY): Returns a list of frames on DISPLAY.
1209 => Already implemented, see frames-on-display-list.
1211 (display-type DISPLAY): Returns the type of DISPLAY, as a
1212 symbol. (See `framep'.)
1213 => Implemented as display-live-p.
1215 (display-device DISPLAY): Returns the name of the device that
1216 DISPLAY uses, as a string. (E.g: "/dev/pts/16", or
1218 => Implemented as display-name.
1222 See next issue why this is necessary.
1224 (Update: The consensus on emacs-devel seems to be to do this via
1225 integer identifiers. That's fine by me.)
1229 -- The following needs to be supported:
1236 The cleanest way to solve this is to allow multiple displays on the
1237 same terminal device; each new emacsclient process should create
1238 its own display. As displays are currently identified by their
1239 device names, this is not possible until struct display becomes
1240 accessible as a Lisp-level object.
1244 -- Miles Bader suggests that C-x C-c on an emacsclient frame should
1245 only close the frame, not exit the entire Emacs session. Update:
1246 see above for a function that does this. Maybe this should be the
1249 (Done. This is the new default. No complaints so far.)
1251 -- Clean up the frame-local variable system. I think it's ugly and
1252 error-prone. But maybe I just haven't yet fully understood it.
1254 (Nothing to do. It doesn't seem ugly any more. It's rather clever.)
1256 -- Support multiple character locales. A version of
1257 `set-locale-environment' needs to be written for setting up
1258 display-local settings on ttys. I think calling
1259 set-display-table-and-terminal-coding-system and
1260 set-keyboard-coding-system would be enough. The language
1261 environment itself should remain a global setting.
1263 (Done, by an ugly hack.)
1265 -- The terminal customization files in term/*.el tend to change global
1266 parameters, which may confuse Emacs with multiple displays. Change
1267 them to tweak only frame-local settings, if possible. (They tend
1268 to call define-key to set function key sequences a lot.)
1270 (Done, by making `function-key-map' terminal-local (i.e., part of
1271 struct kboard). This has probably covered all the remaining problems.)
1273 -- Make `function-key-map' and `key-translation-map' terminal-local.
1277 -- Implement `terminal-local-value' and `set-terminal-local-value' to
1278 allow deterministic access to terminal local bindings. The
1279 encode-kb package can not set up `key-translation-map' without
1280 these. The terminal-local bindings seem to be independent of what
1285 -- xt-mouse.el needs to be adapted for multi-tty. It currently
1286 signals an error on kill-emacs under X, which prevents the user
1287 from exiting Emacs. (Reported by Mnemonikk on freenode.)
1292 -- Having {reset,init}_all_sys_modes in set-input-mode breaks arrow
1293 keys on non-selected terminals under screen, and sometimes on other
1294 terminal types as well. The other function keys continue to work
1295 fine. Sometimes faces on these screens become garbled.
1297 This only seems to affect displays that are of the same terminfo
1298 type as the selected one. Interestingly, in screen Emacs normally
1299 reports the up arrow key as `M-o A', but after the above SNAFU, it
1300 complains about `M-[ a'. UNIX ttys are a complete mystery to me,
1301 but it seems the reset-reinitialize cycle somehow leaves the
1302 non-selected terminals in a different state than usual. I have no
1303 idea how this could happen.
1305 Currently set-input-mode resets only the currently selected
1306 terminal, which seems to somehow work around the problem.
1310 Dan Nicolaescu <dann@ics.uci.edu> writes:
1311 > Some terminals have 2 modes for cursor keys: Application Mode where
1312 > the cursor keys transmit the codes defined in the terminfo entry, and
1313 > Cursor mode. Applications have to send the smkx and rmkx terminfo
1314 > strings to switch between the 2 modes. So Emacs (and emacsclient) have
1315 > to send smkx when initializing and rmkx when quitting (or on
1318 (I think patch-370 fixed this.)
1320 -- This long-standing bug (first reported by Han Boetes) seems to come
1321 and go all the time. It is time to track it down and fix it.
1326 # From another xterm:
1327 emacsclient -e '(y-or-n-p "Do you want me to crash? ")'
1328 # Notice how the answer ends up in the *scratch* buffer
1332 (Fixed in patch-414 after detailed analysis by Kalle Olavi Niemitalo.)
1334 -- normal-erase-is-backspace-mode in simple.el needs to be updated for
1335 multi-tty (rep. by Dan Waber). (The Delete key is broken on X
1338 (Fixed in patch-427.)
1340 -- I think keyboard-translate-table should be made terminal-local.
1342 (Done in patch-431.)
1344 -- The semantics of terminal-local variables are confusing; it is not
1345 clear what binding is in effect in any given time. See if
1346 current_kboard (or at least the terminal-local bindings exported to
1347 Lisp) might be changed to be tied to the selected frame instead.
1348 Currently, `function-key-map' and `key-translation-map' may be
1349 accessed reliably only using the hackish
1350 `(set-)terminal-local-value' functions.
1352 Perhaps there should be a difference between `last-command' &co.
1353 and these more conventional configuration variables.
1354 (E.g. `symbol-value' would use current_kboard to access
1355 `last-command', but SELECTED_FRAME()->display->kboard to get the
1356 value of `function-key-map'.
1358 (Fixed in patch-434.)
1360 -- If the first key pressed on a new tty terminal is a function key,
1361 it is not recognized correctly. May be related to the bug below.
1363 (Seems to have been fixed as a side effect of patch-434. "The bug
1364 below" was the set-input-mode madness.)
1366 (Update: this bug was fixed for good in patch-449. It was tracked
1367 down to a bug in `read_key_sequence': it failed to reinitialize its
1368 local function-key-map/key-translation-map references when it
1369 switched keyboards. I don't understand why did this bug only
1370 appear on brand new frames, though!)
1372 -- Disable connecting to a new X display when we use the GTK toolkit.
1374 (Disabled in patch-450.)
1376 -- Implement automatic forwarding of client environment variables to
1377 forked processes, as discussed on the multi-tty list. Terminal
1378 parameters are now accessible in C code, so the biggest obstacle is
1379 gone. The `getenv_internal' and `child_setup' functions in
1380 callproc.c must be changed to support the following variable:
1382 terminal-local-environment-variables is a variable defined in ...
1384 Enable or disable terminal-local environment variables.
1386 If set to t, `getenv', `setenv' and subprocess creation
1387 functions use the environment variables of the emacsclient
1388 process that created the selected frame, ignoring
1389 `process-environment'.
1391 If set to nil, Emacs uses `process-environment' and ignores
1392 the client environment.
1394 Otherwise, `terminal-local-environment-variables' should be a
1395 list of variable names (represented by Lisp strings) to look
1396 up in the client environment. The rest will come from
1397 `process-environment'.
1399 (Implemented in patch-461; `terminal-getenv', `terminal-setenv' and
1400 `with-terminal-environment' are now replaced by extensions to
1401 `getenv' and `setenv', and the new `local-environment-variables'
1404 (Updated in patch-465 to fix the semantics of let-binding
1405 `process-environment'. `process-environment' was changed to
1406 override all local/global environment variables, and a new variable
1407 `global-environment' was introduced to have `process-environment's
1410 (Updated in patch-466 to fix the case when two emacsclient sessions
1411 share the same terminal, but have different environment. The local
1412 environment lists are now stored as frame parameters, so the
1413 C-level terminal parameters are not strictly necessary any more.)
1415 -- `Fdelete_frame' is called from various critical places where it is
1416 not acceptable for the frame deletion to fail, e.g. from
1417 x_connection_closed after an X error. `Fdelete_frame' now protects
1418 against `delete-frame-functions' throwing an error and preventing a
1419 frame delete. (patch-475)
1421 -- Fix set-input-mode for multi-tty. It's a truly horrible interface;
1422 what if we'd blow it up into several separate functions (with a
1423 compatibility definition)?
1425 (Done. See `set-input-interrupt-mode', `set-output-flow-control',
1426 `set-input-meta-mode' and `set-quit-char'.) (patch-457)
1428 -- Let-binding `overriding-terminal-local-map' on a brand new frame
1429 does not seem to work correctly. (See `fancy-splash-screens'.)
1430 The keymap seems to be set up right, but events go to another
1431 terminal. Or is it `unread-command-events' that gets Emacs
1432 confused? Investigate.
1434 (Emacs was confused because a process filter entered
1435 `recursive-edit' while Emacs was reading input. I added support
1436 for this in the input system.) (patch-489)
1438 -- I smell something funny around pop_kboard's "deleted kboard" case.
1439 Determine what are the circumstances of this case, and fix any
1440 bug that comes to light.
1442 (It happens simply because single_kboard's terminal is sometimes
1443 deleted while executing a command on it, for example the one that
1444 kills the terminal. There was no bug here, but I rewrote the whole
1445 single_kboard mess anyway.) (patch-489)
1447 -- Understand Emacs's low-level input system (it's black magic) :-)
1448 What exactly does interrupt_input do? I tried to disable it for
1449 raw secondary tty support, but it does not seem to do anything
1450 useful. (Update: Look again. X unconditionally enables this, maybe
1451 that's why raw terminal support is broken again. I really do need
1452 to understand input.)
1453 (Update: I am starting to understand the read_key_sequence->read-char
1454 ->kbd_buffer_get_event->read_avail_input->read_socket_hook path. Yay!)
1456 (Update: OK, it all seems so easy now (NOT). Input could be done
1457 synchronously (with wait_reading_process_input), or asynchronously
1458 by SIGIO or polling (SIGALRM). C-g either sets the Vquit_flag,
1459 signals a 'quit condition (when immediate_quit), or throws to
1460 `getcjmp' when Emacs was waiting for input when the C-g event
1463 -- Replace wrong_kboard_jmpbuf with a special return value of
1464 read_char. It is absurd that we use setjmp/longjmp just to return
1465 to the immediate caller.
1467 (Done in patch-500.)
1469 ;;; arch-tag: 8da1619e-2e79-41a8-9ac9-a0485daad17d