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1 Copyright (C) 1993, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
2 Free Software Foundation, Inc.
3 See the end of the file for license conditions.
4
5
6 This directory contains files of elisp that customize Emacs for certain
7 terminal types.
8
9 When Emacs starts, it checks the TERM environment variable to see what type
10 of terminal the user is running on, checks for an elisp file named
11 "term/${TERM}.el", and if one exists, loads it. If that doesn't yield a file
12 that exists, the last hyphen and what follows it is stripped. If that doesn't
13 yield a file that exists, the previous hyphen is stripped, and so on until all
14 hyphens are gone. For example, if the terminal type is `aaa-48-foo', Emacs
15 will try first `term/aaa-48-foo.el', then `term/aaa-48.el' and finally
16 `term/aaa.el'. Each terminal specific file should contain a function
17 named terminal-init-TERMINALNAME (eg terminal-init-aaa-48 for
18 term/aaa-48.el) that Emacs will call in order to initialize the
19 terminal. The terminal files should not contain any top level forms
20 that are executed when the file is loaded, all the initialization
21 actions are performed by the terminal-init-TERMINALNAME functions.
22
23 When writing terminal packages, there are some things it is good to keep in
24 mind.
25
26 First, about keycap names. Your terminal package can create any keycap
27 cookies it likes, but there are good reasons to stick to the set recognized by
28 the X-windows code whenever possible. The key symbols recognized by Emacs
29 are listed in src/term.c; look for the string `keys' in that file.
30
31 For one thing, it means that you'll have the same Emacs key bindings on in
32 terminal mode as on an X console. If there are differences, you can bet
33 they'll frustrate you after you've forgotten about them.
34
35 For another, the X keysms provide a standard set of names that Emacs knows
36 about. It tries to bind many of them to useful things at startup, before your
37 .emacs is read (so you can override them). In some ways, the X keysym standard
38 is a admittedly poor one; it's incomplete, and not well matched to the set of
39 `virtual keys' that UNIX terminfo(3) provides. But, trust us, the alternatives
40 were worse.
41
42 This doesn't mean that if your terminal has a "Cokebottle" key you shouldn't
43 define a [cokebottle] keycap. But if you must define cookies that aren't in
44 that set, try to pattern them on the standard terminfo variable names for
45 clarity; also, for a fighting chance that your binding may be useful to someone
46 else someday.
47
48 For example, if your terminal has a `find' key, observe that terminfo
49 supports a key_find capability and call your cookie [find].
50
51 Here is a complete list, with corresponding X keysyms.
52
53 -----------------------------------------------------------------------------
54 Variable name cap X Keysym Description
55 -------------- --- ------------ -------------------------------------
56 key_down kd down Sent by terminal down arrow key
57 key_up ku up Sent by terminal up arrow key
58 key_left kl left Sent by terminal left arrow key
59 key_right kr right Sent by terminal right arrow key
60 key_home kh home Sent by home key.
61 key_backspace kb Sent by backspace key
62 key_dl kd deleteline Sent by delete line key.
63 key_il kA insertline Sent by insert line.
64 key_dc kD Sent by delete character key.
65 key_ic kI insertchar (1) Sent by ins char/enter ins mode key.
66 key_eic KM Sent by rmir or smir in insert mode.
67 key_clear kC Sent by clear screen or erase key.
68 key_eos kS Sent by clear-to-end-of-screen key.
69 key_eol kE Sent by clear-to-end-of-line key.
70 key_sf kF Sent by scroll-forward/down key
71 key_sr kR Sent by scroll-backward/up key
72 key_npage kN next (2) Sent by next-page key
73 key_ppage kP prior (2) Sent by previous-page key
74 key_stab kT Sent by set-tab key
75 key_ctab kt Sent by clear-tab key
76 key_catab ka Sent by clear-all-tabs key.
77 key_enter @8 kp-enter Enter/send (unreliable)
78 key_print %9 print print or copy
79 key_ll kH Sent by home-down key
80 key_a1 K1 kp-1 Upper left of keypad
81 key_a3 K3 kp-3 Upper right of keypad
82 key_b2 K2 kp-5 Center of keypad
83 key_c1 K4 kp-7 Lower left of keypad
84 key_c3 K5 kp-9 Lower right of keypad
85 key_btab kB backtab Back tab key
86 key_beg @1 begin beg(inning) key
87 key_cancel @2 cancel cancel key
88 key_close @3 close key
89 key_command @4 execute (3) cmd (command) key
90 key_copy @5 copy key
91 key_create @6 create key
92 key_end @7 end end key
93 key_exit @9 exit key
94 key_find @0 find key
95 key_help %1 help key
96 key_mark %2 mark key
97 key_message %3 message key
98 key_move %4 move key
99 key_next %5 next (2) next object key
100 key_open %6 open key
101 key_options %7 menu (3) options key
102 key_previous %8 previous (2) previous object key
103 key_redo %0 redo redo key
104 key_reference &1 ref(erence) key
105 key_refresh &2 refresh key
106 key_replace &3 replace key
107 key_restart &4 reset (3) restart key
108 key_resume &5 resume key
109 key_save &6 save key
110 key_sbeg &9 shifted beginning key
111 key_select *6 select select key
112 key_suspend &7 suspend key
113 key_undo &8 undo undo key
114
115 key_scancel &0 shifted cancel key
116 key_scommand *1 shifted command key
117 key_scopy *2 shifted copy key
118 key_screate *3 shifted create key
119 key_sdc *4 shifted delete char key
120 key_sdl *5 shifted delete line key
121 key_send *7 shifted end key
122 key_seol *8 shifted clear line key
123 key_sexit *9 shifted exit key
124 key_sf kF shifted find key
125 key_shelp #1 shifted help key
126 key_shome #2 shifted home key
127 key_sic #3 shifted input key
128 key_sleft #4 shifted left arrow key
129 key_smessage %a shifted message key
130 key_smove %b shifted move key
131 key_snext %c shifted next key
132 key_soptions %d shifted options key
133 key_sprevious %e shifted prev key
134 key_sprint %f shifted print key
135 key_sredo %g shifted redo key
136 key_sreplace %h shifted replace key
137 key_sright %i shifted right arrow
138 key_sresume %j shifted resume key
139 key_ssave !1 shifted save key
140 key_suspend !2 shifted suspend key
141 key_sundo !3 shifted undo key
142
143 key_f0 k0 f0 (4) function key 0
144 key_f1 k1 f1 function key 1
145 key_f2 k2 f2 function key 2
146 key_f3 k3 f3 function key 3
147 key_f4 k4 f4 function key 4
148 key_f5 k5 f5 function key 5
149 key_f6 k6 f6 function key 6
150 key_f7 k7 f7 function key 7
151 key_f8 k8 f8 function key 8
152 key_f9 k9 f9 function key 9
153 key_f10 k; f10 (4) function key 10
154 key_f11 F1 f11 function key 11
155 : : : :
156 key_f35 FP f35 function key 35
157 key_f36 FQ function key 36
158 : : : :
159 key_f64 k1 function key 64
160
161 (1) The terminfo documentation says this may be the 'insert character' or
162 `enter insert mode' key. Accordingly, key_ic is mapped to the `insertchar'
163 keysym if there is also a key_dc key; otherwise it's mapped to `insert'.
164 The presumption is that keyboards with `insert character' keys usually
165 have `delete character' keys paired with them.
166
167 (2) If there is no key_next key but there is a key_npage key, key_npage
168 will be bound to the `next' keysym. If there is no key_previous key but
169 there is a key_ppage key, key_ppage will be bound to the `previous' keysym.
170
171 (3) Sorry, these are not exact but they're the best we can do.
172
173 (4) The uses of the "k0" capability are inconsistent; sometimes it
174 describes F10, whereas othertimes it describes F0 and "k;" describes F10.
175 Emacs attempts to politely accommodate both systems by testing for
176 "k;", and if it is present, assuming that "k0" denotes F0, otherwise F10.
177 -----------------------------------------------------------------------------
178
179 The following X keysyms do *not* have terminfo equivalents. These are
180 the cookies your terminal package will have to set up itself, if you want them:
181
182 break
183 system
184 user
185 kp-backtab
186 kp-space
187 kp-tab
188 kp-f1
189 kp-f2
190 kp-f3
191 kp-f4
192 kp-multiply
193 kp-add
194 kp-separator
195 kp-subtract
196 kp-decimal
197 kp-divide
198 kp-0
199 kp-2
200 kp-4
201 kp-6
202 kp-8
203 kp-equal
204
205 In general, you should not bind any of the standard keysym names to
206 functions in a terminal package. There's code in loaddefs.el that does that;
207 the less people make exceptions to that, the more consistent an interface Emacs
208 will have across different keyboards. Those exceptions should go in your
209 .emacs file.
210
211 Finally, if you're using a USL UNIX or a Sun box or anything else with the
212 USL version of curses(3) on it, bear in mind that the original curses(3) had
213 (and still has) a very much smaller set of keycaps. In fact, the reliable
214 ones were just the arrow keys and the first ten function keys. If you care
215 about making your package portable to older Berkeley machines, don't count on
216 the setup code to bind anything else.
217
218 If your terminal's arrow key sequences are so funky that they conflict with
219 normal Emacs key bindings, the package should set up a function called
220 (enable-foo-arrow-keys), where `foo' becomes the terminal name, and leave
221 it up to the user's .emacs file whether to call it.
222
223 Before writing a terminal-support package, it's a good idea to read the
224 existing ones and learn the common conventions.
225
226 \f
227 This file is part of GNU Emacs.
228
229 GNU Emacs is free software; you can redistribute it and/or modify
230 it under the terms of the GNU General Public License as published by
231 the Free Software Foundation; either version 3, or (at your option)
232 any later version.
233
234 GNU Emacs is distributed in the hope that it will be useful,
235 but WITHOUT ANY WARRANTY; without even the implied warranty of
236 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
237 GNU General Public License for more details.
238
239 You should have received a copy of the GNU General Public License
240 along with GNU Emacs; see the file COPYING. If not, write to the
241 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
242 Boston, MA 02110-1301, USA.