1
2
3
4
5
6
7
8
9
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
118
119
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
175
176
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
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
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
522
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
811
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
1123
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
|
This is screen.info, produced by makeinfo version 4.0 from
./screen.texinfo.
INFO-DIR-SECTION General Commands
START-INFO-DIR-ENTRY
* Screen: (screen). Full-screen window manager.
END-INFO-DIR-ENTRY
This file documents the `Screen' virtual terminal manager.
Copyright (c) 1993-2002 Free Software Foundation, Inc.
Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.
Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided that
the entire resulting derived work is distributed under the terms of a
permission notice identical to this one.
Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that this permission notice may be stated in a
translation approved by the Foundation.
File: screen.info, Node: Next and Previous, Next: Other Window, Up: Selecting
Moving Back and Forth
=====================
- Command: next
(`C-a <SPC>', `C-a n', `C-a C-n')
Switch to the next window. This command can be used repeatedly to
cycle through the list of windows. (On some terminals, C-<SPC>
generates a NUL character, so you must release the control key
before pressing space.)
- Command: prev
(`C-a p', `C-a C-p')
Switch to the previous window (the opposite of `C-a n').
File: screen.info, Node: Other Window, Next: Select, Prev: Next and Previous, Up: Selecting
Other Window
============
- Command: other
(`C-a C-a')
Switch to the last window displayed. Note that this command
defaults to the command character typed twice, unless overridden.
For instance, if you use the option `-e]x', this command becomes
`]]' (*note Command Character::).
File: screen.info, Node: Select, Next: Windowlist, Prev: Other Window, Up: Selecting
Select
======
- Command: select [n]
(`C-a N', `C-a '')
Switch to the window with the number N. If no window number is
specified, you get prompted for an identifier. This can be a
window name (title) or a number. When a new window is
established, the lowest available number is assigned to this
window. Thus, the first window can be activated by `select 0';
there can be no more than 10 windows present simultaneously
(unless screen is compiled with a higher MAXWIN setting). The
special command `select -' switches to a blank window.
File: screen.info, Node: Windowlist, Prev: Select, Up: Selecting
Windowlist
==========
- Command: windowlist [-b] | string [STRING] | title [TITLE]
(`C-a "')
Display all windows in a table for visual window selection. The
desired window can be selected via the standard movement keys
(*note Movement::) and activated via the return key. If the `-b'
option is given, screen will switch to the blank window before
presenting the list, so that the current window is also selectable.
The table format can be changed with the string and title option,
the title is displayed as table heading, while the lines are made
by using the string setting. The default setting is `Num
Name%=Flags' for the title and `%3n %t%=%f' for the lines. See the
string escapes chapter (*note String Escapes::) for more codes
(e.g. color settings).
File: screen.info, Node: Session Management, Next: Regions, Prev: Selecting, Up: Top
Session Management Commands
***************************
Perhaps the most useful feature of `screen' is the way it allows the
user to move a session between terminals, by detaching and reattaching.
This also makes life easier for modem users who have to deal with
unexpected loss of carrier.
* Menu:
* Detach:: Disconnect `screen' from your terminal.
* Power Detach:: Detach and log out.
* Lock:: Lock your terminal temporarily.
* Multiuser Session:: Changing number of allowed users.
* Session Name:: Rename your session for later reattachment.
* Suspend:: Suspend your session.
* Quit:: Terminate your session.
File: screen.info, Node: Detach, Next: Power Detach, Up: Session Management
Detach
======
- Command: autodetach state
(none)
Sets whether `screen' will automatically detach upon hangup, which
saves all your running programs until they are resumed with a
`screen -r' command. When turned off, a hangup signal will
terminate `screen' and all the processes it contains. Autodetach is
on by default.
- Command: detach
(`C-a d', `C-a C-d')
Detach the `screen' session (disconnect it from the terminal and
put it into the background). A detached `screen' can be resumed by
invoking `screen' with the `-r' option (*note Invoking Screen::).
The `-h' option tells screen to immediately close the connection
to the terminal (`hangup').
- Command: password [crypted_pw]
(none)
Present a crypted password in your `.screenrc' file and screen will
ask for it, whenever someone attempts to resume a detached
session. This is useful, if you have privileged programs running
under `screen' and you want to protect your session from reattach
attempts by users that managed to assume your uid. (I.e. any
superuser.) If no crypted password is specified, screen prompts
twice a password and places its encryption in the paste buffer.
Default is `none', which disables password checking.
File: screen.info, Node: Power Detach, Next: Lock, Prev: Detach, Up: Session Management
Power Detach
============
- Command: pow_detach
(`C-a D')
Mainly the same as `detach', but also sends a HANGUP signal to the
parent process of `screen'.
_Caution_: This will result in a logout if `screen' was started
from your login shell.
- Command: pow_detach_msg [message]
(none)
The MESSAGE specified here is output whenever a power detach is
performed. It may be used as a replacement for a logout message or
to reset baud rate, etc. Without parameter, the current message
is shown.
File: screen.info, Node: Lock, Next: Multiuser Session, Prev: Power Detach, Up: Session Management
Lock
====
- Command: lockscreen
(`C-a x', `C-a C-x')
Call a screenlock program (`/local/bin/lck' or `/usr/bin/lock' or
a builtin, if no other is available). Screen does not accept any
command keys until this program terminates. Meanwhile processes in
the windows may continue, as the windows are in the detached state.
The screenlock program may be changed through the environment
variable `$LOCKPRG' (which must be set in the shell from which
`screen' is started) and is executed with the user's uid and gid.
Warning: When you leave other shells unlocked and have no password
set on `screen', the lock is void: One could easily re-attach from
an unlocked shell. This feature should rather be called
`lockterminal'.
File: screen.info, Node: Multiuser Session, Next: Session Name, Prev: Lock, Up: Session Management
Multiuser Session
=================
These commands allow other users to gain access to one single
`screen' session. When attaching to a multiuser `screen' the
sessionname is specified as `username/sessionname' to the `-S' command
line option. `Screen' must be compiled with multiuser support to
enable features described here.
* Menu:
* Multiuser:: Enable / Disable multiuser mode.
* Acladd:: Enable a specific user.
* Aclchg:: Change a users permissions.
* Acldel:: Disable a specific user.
* Aclgrp:: Grant a user permissions to other users.
* Displays:: List all active users at their displays.
* Umask:: Predefine access to new windows.
* Wall:: Write a message to all users.
* Writelock:: Grant exclusive window access.
* Su:: Substitute user.
File: screen.info, Node: Multiuser, Next: Acladd, Up: Multiuser Session
Multiuser
---------
- Command: multiuser STATE
(none)
Switch between single-user and multi-user mode. Standard screen
operation is single-user. In multi-user mode the commands
`acladd', `aclchg' and `acldel' can be used to enable (and
disable) other users accessing this `screen'.
File: screen.info, Node: Acladd, Next: Aclchg, Prev: Multiuser, Up: Multiuser Session
Acladd
------
- Command: acladd USERNAMES
- Command: addacl USERNAMES
(none)
Enable users to fully access this screen session. USERNAMES can be
one user or a comma separated list of users. This command enables
to attach to the `screen' session and performs the equivalent of
`aclchg USERNAMES +rwx "#?"'. To add a user with restricted access,
use the `aclchg' command below. `Addacl' is a synonym to `acladd'.
Multi-user mode only.
File: screen.info, Node: Aclchg, Next: Acldel, Prev: Acladd, Up: Multiuser Session
Aclchg
------
- Command: aclchg USERNAMES PERMBITS LIST
- Command: chacl USERNAMES PERMBITS LIST
(none)
Change permissions for a comma separated list of users.
Permission bits are represented as `r', `w' and `x'. Prefixing
`+' grants the permission, `-' removes it. The third parameter is
a comma separated list of commands or windows (specified either by
number or title). The special list `#' refers to all windows, `?'
to all commands. If USERNAMES consists of a single `*', all known
users is affected. A command can be executed when the user has
the `x' bit for it. The user can type input to a window when he
has its `w' bit set and no other user obtains a writelock for this
window. Other bits are currently ignored. To withdraw the
writelock from another user in e.g. window 2: `aclchg USERNAME
-w+w 2'. To allow read-only access to the session: `aclchg
USERNAME -w "#"'. As soon as a user's name is known to screen, he
can attach to the session and (per default) has full permissions
for all command and windows. Execution permission for the acl
commands, `at' and others should also be removed or the user may
be able to regain write permission. `Chacl' is a synonym to
`aclchg'. Multi-user mode only.
File: screen.info, Node: Acldel, Next: Aclgrp, Prev: Aclchg, Up: Multiuser Session
Acldel
------
- Command: acldel USERNAME
(none)
Remove a user from screen's access control list. If currently
attached, all the user's displays are detached from the session.
He cannot attach again. Multi-user mode only.
File: screen.info, Node: Aclgrp, Next: Displays, Prev: Acldel, Up: Multiuser Session
Aclgrp
------
- Command: aclgrp USERNAME [GROUPNAME]
(none)
Creates groups of users that share common access rights. The name
of the group is the username of the group leader. Each member of
the group inherits the permissions that are granted to the
group leader. That means, if a user fails an access check, another
check is made for the group leader. A user is removed from all
groups the special value `none' is used for GROUPNAME. If the
second parameter is omitted all groups the user is in are listed.
File: screen.info, Node: Displays, Next: Umask, Prev: Aclgrp, Up: Multiuser Session
Displays
--------
- Command: displays
(`C-a *')
Shows a tabular listing of all currently connected user
front-ends (displays). This is most useful for multiuser
sessions.
File: screen.info, Node: Umask, Next: Wall, Prev: Displays, Up: Multiuser Session
aclumask
--------
- Command: aclumask [USERS]+/-BITS ...
- Command: umask [USERS]+/-BITS ...
(none)
This specifies the access other users have to windows that will
be created by the caller of the command. USERS may be no, one
or a comma separated list of known usernames. If no users are
specified, a list of all currently known users is assumed. BITS
is any combination of access control bits allowed defined
with the `aclchg' command. The special username `?' predefines the
access that not yet known users will be granted to any
window initially. The special username `??' predefines the access
that not yet known users are granted to any command. Rights of
the special username nobody cannot be changed (see the `su'
command). `Umask' is a synonym to `aclumask'.
File: screen.info, Node: Wall, Next: Writelock, Prev: Umask, Up: Multiuser Session
Wall
----
- Command: wall MESSAGE
(none)
Write a message to all displays. The message will appear in the
terminal's status line.
File: screen.info, Node: Writelock, Next: Su, Prev: Wall, Up: Multiuser Session
Writelock
---------
- Command: writelock ON|OFF|AUTO
(none)
In addition to access control lists, not all users may be able to
write to the same window at once. Per default, writelock is in
`auto' mode and grants exclusive input permission to the user who
is the first to switch to the particular window. When he leaves
the window, other users may obtain the writelock (automatically).
The writelock of the current window is disabled by the command
`writelock off'. If the user issues the command `writelock on' he
keeps the exclusive write permission while switching to other
windows.
- Command: defwritelock ON|OFF|AUTO
(none)
Sets the default writelock behavior for new windows. Initially all
windows will be created with no writelocks.
File: screen.info, Node: Su, Prev: Writelock, Up: Multiuser Session
Su
--
- Command: su [USERNAME [PASSWORD [PASSWORD2]]]
(none)
Substitute the user of a display. The command prompts for all
parameters that are omitted. If passwords are specified as
parameters, they have to be specified un-crypted. The first
password is matched against the systems passwd database, the
second password is matched against the `screen' password as
set with the commands `acladd' or `password'. `Su' may be useful
for the `screen' administrator to test multiuser setups. When
the identification fails, the user has access to the commands
available for user `nobody'. These are `detach', `license',
`version', `help' and `displays'.
File: screen.info, Node: Session Name, Next: Suspend, Prev: Multiuser Session, Up: Session Management
Session Name
============
- Command: sessionname [NAME]
(none)
Rename the current session. Note that for `screen -list' the name
shows up with the process-id prepended. If the argument NAME is
omitted, the name of this session is displayed.
_Caution_: The `$STY' environment variable still reflects the old
name. This may result in confusion. The default is constructed
from the tty and host names.
File: screen.info, Node: Suspend, Next: Quit, Prev: Session Name, Up: Session Management
Suspend
=======
- Command: suspend
(`C-a z', `C-a C-z')
Suspend `screen'. The windows are in the detached state while
`screen' is suspended. This feature relies on the parent shell
being able to do job control.
File: screen.info, Node: Quit, Prev: Suspend, Up: Session Management
Quit
====
- Command: quit
(`C-a C-\')
Kill all windows and terminate `screen'. Note that on VT100-style
terminals the keys `C-4' and `C-\' are identical. So be careful
not to type `C-a C-4' when selecting window no. 4. Use the empty
bind command (as in `bind "^\"') to remove a key binding (*note
Key Binding::).
File: screen.info, Node: Regions, Next: Window Settings, Prev: Session Management, Up: Top
Regions
*******
Screen has the ability to display more than one window on the user's
display. This is done by splitting the screen in regions, which can
contain different windows.
* Menu:
* Split:: Split a region into two
* Focus:: Change to the next region
* Only:: Delete all other regions
* Remove:: Delete the current region
* Resize:: Grow or shrink a region
* Caption:: Control the window's caption
* Fit:: Resize a window to fit the region
File: screen.info, Node: Split, Next: Focus, Up: Regions
Split
=====
- Command: split
(`C-a S')
Split the current region into two new ones. All regions on the
display are resized to make room for the new region. The blank
window is displayed on the new region.
File: screen.info, Node: Focus, Next: Only, Prev: Split, Up: Regions
Focus
=====
- Command: focus
(`C-a <Tab>')
Move the input focus to the next region. This is done in a cyclic
way so that the top region is selected after the bottom one. If no
subcommand is given it defaults to `down'. `up' cycles in the
opposite order, `top' and `bottom' go to the top and bottom region
respectively. Useful bindings are (j and k as in vi)
bind j focus down
bind k focus up
bind t focus top
bind b focus bottom
File: screen.info, Node: Only, Next: Remove, Prev: Focus, Up: Regions
Only
====
- Command: only
(`C-a Q')
Kill all regions but the current one.
File: screen.info, Node: Remove, Next: Resize, Prev: Only, Up: Regions
Remove
======
- Command: remove
(`C-a X')
Kill the current region. This is a no-op if there is only one
region.
File: screen.info, Node: Resize, Next: Caption, Prev: Remove, Up: Regions
Resize
======
- Command: resize [(+/-)LINES]
(none)
Resize the current region. The space will be removed from or added
to the region below or if there's not enough space from the region
above.
resize +N increase current region height by N
resize -N decrease current region height by N
resize N set current region height to N
resize = make all windows equally high
resize max maximize current region height
resize min minimize current region height
File: screen.info, Node: Caption, Next: Fit, Prev: Resize, Up: Regions
Caption
=======
- Command: caption `always'|`splitonly' [string]
- Command: caption `string' [string]
(none)
This command controls the display of the window captions. Normally
a caption is only used if more than one window is shown on the
display (split screen mode). But if the type is set to `always',
`screen' shows a caption even if only one window is displayed. The
default is `splitonly'.
The second form changes the text used for the caption. You can use
all string escapes (*note String Escapes::). `Screen' uses a
default of `%3n %t'.
You can mix both forms by providing the string as an additional
argument.
File: screen.info, Node: Fit, Prev: Caption, Up: Regions
Fit
===
- Command: fit
(`C-a F')
Change the window size to the size of the current region. This
command is needed because screen doesn't adapt the window size
automatically if the window is displayed more than once.
File: screen.info, Node: Window Settings, Next: Virtual Terminal, Prev: Regions, Up: Top
Window Settings
***************
These commands control the way `screen' treats individual windows in
a session. *Note Virtual Terminal::, for commands to control the
terminal emulation itself.
* Menu:
* Naming Windows:: Control the name of the window
* Console:: See the host's console messages
* Kill:: Destroy an unwanted window
* Login:: Control `/etc/utmp' logging
* Mode:: Control the file mode of the pty
* Monitor:: Watch for activity in a window
* Windows:: List the active windows
* Hardstatus:: Set a window's hardstatus line
File: screen.info, Node: Naming Windows, Next: Console, Up: Window Settings
Naming Windows (Titles)
=======================
You can customize each window's name in the window display (viewed
with the `windows' command (*note Windows::) by setting it with one of
the title commands. Normally the name displayed is the actual command
name of the program created in the window. However, it is sometimes
useful to distinguish various programs of the same name or to change
the name on-the-fly to reflect the current state of the window.
The default name for all shell windows can be set with the
`shelltitle' command (*note Shell::). You can specify the name you
want for a window with the `-t' option to the `screen' command when the
window is created (*note Screen Command::). To change the name after
the window has been created you can use the title-string escape-sequence
(`<ESC> k NAME <ESC> \') and the `title' command (C-a A). The former
can be output from an application to control the window's name under
software control, and the latter will prompt for a name when typed.
You can also bind predefined names to keys with the `title' command to
set things quickly without prompting.
* Menu:
* Title Command:: The `title' command.
* Dynamic Titles:: Make shell windows change titles dynamically.
* Title Prompts:: Set up your shell prompt for dynamic Titles.
* Title Screenrc:: Set up Titles in your `.screenrc'.
File: screen.info, Node: Title Command, Next: Dynamic Titles, Up: Naming Windows
Title Command
-------------
- Command: title [windowtitle]
(`C-a A')
Set the name of the current window to WINDOWALIAS. If no name is
specified, screen prompts for one.
File: screen.info, Node: Dynamic Titles, Next: Title Prompts, Prev: Title Command, Up: Naming Windows
Dynamic Titles
--------------
`screen' has a shell-specific heuristic that is enabled by setting
the window's name to SEARCH|NAME and arranging to have a null title
escape-sequence output as a part of your prompt. The SEARCH portion
specifies an end-of-prompt search string, while the NAME portion
specifies the default shell name for the window. If the NAME ends in a
`:' `screen' will add what it believes to be the current command
running in the window to the end of the specified name (e.g. NAME:CMD).
Otherwise the current command name supersedes the shell name while it
is running.
Here's how it works: you must modify your shell prompt to output a
null title-escape-sequence (<ESC> k <ESC> \) as a part of your prompt.
The last part of your prompt must be the same as the string you
specified for the SEARCH portion of the title. Once this is set up,
`screen' will use the title-escape-sequence to clear the previous
command name and get ready for the next command. Then, when a newline
is received from the shell, a search is made for the end of the prompt.
If found, it will grab the first word after the matched string and use
it as the command name. If the command name begins with `!', `%', or
`^', `screen' will use the first word on the following line (if found)
in preference to the just-found name. This helps csh users get more
accurate titles when using job control or history recall commands.
File: screen.info, Node: Title Prompts, Next: Title Screenrc, Prev: Dynamic Titles, Up: Naming Windows
Setting up your prompt for shell titles
---------------------------------------
One thing to keep in mind when adding a null title-escape-sequence
to your prompt is that some shells (like the csh) count all the
non-control characters as part of the prompt's length. If these
invisible characters aren't a multiple of 8 then backspacing over a tab
will result in an incorrect display. One way to get around this is to
use a prompt like this:
set prompt='[0000mk\% '
The escape-sequence `[0000m' not only normalizes the character
attributes, but all the zeros round the length of the invisible
characters up to 8.
Tcsh handles escape codes in the prompt more intelligently, so you
can specify your prompt like this:
set prompt="%{\ek\e\\%}\% "
Bash users will probably want to echo the escape sequence in the
PROMPT_COMMAND:
PROMPT_COMMAND='echo -n -e "\033k\033\134"'
(I used `\134' to output a `\' because of a bug in v1.04).
File: screen.info, Node: Title Screenrc, Prev: Title Prompts, Up: Naming Windows
Setting up shell titles in your `.screenrc'
-------------------------------------------
Here are some .screenrc examples:
screen -t top 2 nice top
Adding this line to your .screenrc would start a niced version of the
`top' command in window 2 named `top' rather than `nice'.
shelltitle '> |csh'
screen 1
This file would start a shell using the given shelltitle. The title
specified is an auto-title that would expect the prompt and the typed
command to look something like the following:
/usr/joe/src/dir> trn
(it looks after the '> ' for the command name). The window status
would show the name `trn' while the command was running, and revert to
`csh' upon completion.
bind R screen -t '% |root:' su
Having this command in your .screenrc would bind the key sequence
`C-a R' to the `su' command and give it an auto-title name of `root:'.
For this auto-title to work, the screen could look something like this:
% !em
emacs file.c
Here the user typed the csh history command `!em' which ran the
previously entered `emacs' command. The window status would show
`root:emacs' during the execution of the command, and revert to simply
`root:' at its completion.
bind o title
bind E title ""
bind u title (unknown)
The first binding doesn't have any arguments, so it would prompt you
for a title when you type `C-a o'. The second binding would clear an
auto-titles current setting (C-a E). The third binding would set the
current window's title to `(unknown)' (C-a u).
File: screen.info, Node: Console, Next: Kill, Prev: Naming Windows, Up: Window Settings
Console
=======
- Command: console [STATE]
(none)
Grabs or un-grabs the machines console output to a window. When
the argument is omitted the current state is displayed. _Note_:
Only the owner of `/dev/console' can grab the console output. This
command is only available if the host supports the ioctl
`TIOCCONS'.
File: screen.info, Node: Kill, Next: Login, Prev: Console, Up: Window Settings
Kill
====
- Command: kill
(`C-a k', `C-a C-k')
Kill the current window.
If there is an `exec' command running (*note Exec::) then it is
killed. Otherwise the process (e.g. shell) running in the window
receives a `HANGUP' condition, the window structure is removed and
screen (your display) switches to another window. When the last
window is destroyed, `screen' exits. After a kill screen switches
to the previously displayed window.
_Caution_: `emacs' users may find themselves killing their `emacs'
session when trying to delete the current line. For this reason,
it is probably wise to use a different command character (*note
Command Character::) or rebind `kill' to another key sequence,
such as `C-a K' (*note Key Binding::).
File: screen.info, Node: Login, Next: Mode, Prev: Kill, Up: Window Settings
Login
=====
- Command: deflogin state
(none)
Same as the `login' command except that the default setting for new
windows is changed. This defaults to `on' unless otherwise
specified at compile time (*note Installation::). Both commands
are only present when `screen' has been compiled with utmp support.
- Command: login [state]
(`C-a L')
Adds or removes the entry in `/etc/utmp' for the current window.
This controls whether or not the window is "logged in". In
addition to this toggle, it is convenient to have "log in" and
"log out" keys. For instance, `bind I login on' and `bind O login
off' will map these keys to be `C-a I' and `C-a O' (*note Key
Binding::).
File: screen.info, Node: Mode, Next: Monitor, Prev: Login, Up: Window Settings
Mode
====
- Command: defmode mode
(none)
The mode of each newly allocated pseudo-tty is set to MODE. MODE
is an octal number as used by chmod(1). Defaults to 0622 for
windows which are logged in, 0600 for others (e.g. when `-ln' was
specified for creation, *note Screen Command::).
File: screen.info, Node: Monitor, Next: Windows, Prev: Mode, Up: Window Settings
Monitoring
==========
- Command: activity message
(none)
When any activity occurs in a background window that is being
monitored, `screen' displays a notification in the message line.
The notification message can be redefined by means of the
`activity' command. Each occurrence of `%' in MESSAGE is replaced
by the number of the window in which activity has occurred, and
each occurrence of `^G' is replaced by the definition for bell in
your termcap (usually an audible bell). The default message is
'Activity in window %n'
Note that monitoring is off for all windows by default, but can be
altered by use of the `monitor' command (`C-a M').
- Command: defmonitor state
(none)
Same as the `monitor' command except that the default setting for
new windows is changed. Initial setting is `off'.
- Command: monitor [state]
(`C-a M')
Toggles monitoring of the current window. When monitoring is
turned on and the affected window is switched into the background,
the activity notification message will be displayed in the status
line at the first sign of output, and the window will also be
marked with an `@' in the window-status display (*note Windows::).
Monitoring defaults to `off' for all windows.
File: screen.info, Node: Windows, Next: Hardstatus, Prev: Monitor, Up: Window Settings
Windows
=======
- Command: windows
(`C-a w', `C-a C-w')
Uses the message line to display a list of all the windows. Each
window is listed by number with the name of the program running in
the window (or its title).
The current window is marked with a `*'; the previous window is
marked with a `-'; all the windows that are logged in are marked
with a `$' (*note Login::); a background window that has received
a bell is marked with a `!'; a background window that is being
monitored and has had activity occur is marked with an `@' (*note
Monitor::); a window which has output logging turned on is marked
with `(L)'; windows occupied by other users are marked with `&' or
`&&' if the window is shared by other users; windows in the zombie
state are marked with `Z'.
If this list is too long to fit on the terminal's status line only
the portion around the current window is displayed.
File: screen.info, Node: Hardstatus, Prev: Windows, Up: Window Settings
Hardstatus
==========
`Screen' maintains a hardstatus line for every window. If a window
gets selected, the display's hardstatus will be updated to match the
window's hardstatus line. The hardstatus line can be changed with the
ANSI Application Program Command (APC): `ESC_<string>ESC\'. As a
convenience for xterm users the sequence `ESC]0..2;<string>^G' is also
accepted.
- Command: defhstatus [status]
(none)
The hardstatus line that all new windows will get is set to STATUS.
This command is useful to make the hardstatus of every window
display the window number or title or the like. STATUS may
contain the same directives as in the window messages, but the
directive escape character is `^E' (octal 005) instead of `%'.
This was done to make a misinterpretation of program generated
hardstatus lines impossible. If the parameter STATUS is omitted,
the current default string is displayed. Per default the
hardstatus line of new windows is empty.
- Command: hstatus status
(none)
Changes the current window's hardstatus line to STATUS.
File: screen.info, Node: Virtual Terminal, Next: Copy and Paste, Prev: Window Settings, Up: Top
Virtual Terminal
****************
Each window in a `screen' session emulates a VT100 terminal, with
some extra functions added. The VT100 emulator is hard-coded, no other
terminal types can be emulated. The commands described here modify the
terminal emulation.
* Menu:
* Control Sequences:: Details of the internal VT100 emulation.
* Input Translation:: How keystrokes are remapped.
* Digraph:: Entering digraph sequences.
* Bell:: Getting your attention.
* Clear:: Clear the window display.
* Info:: Terminal emulation statistics.
* Redisplay:: When the display gets confusing.
* Wrap:: Automatic margins.
* Reset:: Recovering from ill-behaved applications.
* Window Size:: Changing the size of your terminal.
* Character Processing:: Change the effect of special characters.
File: screen.info, Node: Control Sequences, Next: Input Translation, Up: Virtual Terminal
Control Sequences
=================
The following is a list of control sequences recognized by `screen'.
`(V)' and `(A)' indicate VT100-specific and ANSI- or ISO-specific
functions, respectively.
ESC E Next Line
ESC D Index
ESC M Reverse Index
ESC H Horizontal Tab Set
ESC Z Send VT100 Identification String
ESC 7 (V) Save Cursor and Attributes
ESC 8 (V) Restore Cursor and Attributes
ESC [s (A) Save Cursor and Attributes
ESC [u (A) Restore Cursor and Attributes
ESC c Reset to Initial State
ESC g Visual Bell
ESC Pn p Cursor Visibility (97801)
Pn = 6 Invisible
7 Visible
ESC = (V) Application Keypad Mode
ESC > (V) Numeric Keypad Mode
ESC # 8 (V) Fill Screen with E's
ESC \ (A) String Terminator
ESC ^ (A) Privacy Message String (Message Line)
ESC ! Global Message String (Message Line)
ESC k Title Definition String
ESC P (A) Device Control String
Outputs a string directly to the host
terminal without interpretation.
ESC _ (A) Application Program Command (Hardstatus)
ESC ] 0 ; string ^G (A) Operating System Command (Hardstatus, xterm
title hack)
ESC ] 83 ; cmd ^G (A) Execute screen command. This only works if
multi-user support is compiled into screen.
The pseudo-user ":window:" is used to check
the access control list. Use "addacl :window:
-rwx #?" to create a user with no rights and
allow only the needed commands.
Control-N (A) Lock Shift G1 (SO)
Control-O (A) Lock Shift G0 (SI)
ESC n (A) Lock Shift G2
ESC o (A) Lock Shift G3
ESC N (A) Single Shift G2
ESC O (A) Single Shift G3
ESC ( Pcs (A) Designate character set as G0
ESC ) Pcs (A) Designate character set as G1
ESC * Pcs (A) Designate character set as G2
ESC + Pcs (A) Designate character set as G3
ESC [ Pn ; Pn H Direct Cursor Addressing
ESC [ Pn ; Pn f same as above
ESC [ Pn J Erase in Display
Pn = None or 0 From Cursor to End of Screen
1 From Beginning of Screen to Cursor
2 Entire Screen
ESC [ Pn K Erase in Line
Pn = None or 0 From Cursor to End of Line
1 From Beginning of Line to Cursor
2 Entire Line
ESC [ Pn X Erase character
ESC [ Pn A Cursor Up
ESC [ Pn B Cursor Down
ESC [ Pn C Cursor Right
ESC [ Pn D Cursor Left
ESC [ Pn E Cursor next line
ESC [ Pn F Cursor previous line
ESC [ Pn G Cursor horizontal position
ESC [ Pn ` same as above
ESC [ Pn d Cursor vertical position
ESC [ Ps ;...; Ps m Select Graphic Rendition
Ps = None or 0 Default Rendition
1 Bold
2 (A) Faint
3 (A) Standout Mode (ANSI: Italicized)
4 Underlined
5 Blinking
7 Negative Image
22 (A) Normal Intensity
23 (A) Standout Mode off (ANSI: Italicized off)
24 (A) Not Underlined
25 (A) Not Blinking
27 (A) Positive Image
30 (A) Foreground Black
31 (A) Foreground Red
32 (A) Foreground Green
33 (A) Foreground Yellow
34 (A) Foreground Blue
35 (A) Foreground Magenta
36 (A) Foreground Cyan
37 (A) Foreground White
39 (A) Foreground Default
40 (A) Background Black
... ...
49 (A) Background Default
ESC [ Pn g Tab Clear
Pn = None or 0 Clear Tab at Current Position
3 Clear All Tabs
ESC [ Pn ; Pn r (V) Set Scrolling Region
ESC [ Pn I (A) Horizontal Tab
ESC [ Pn Z (A) Backward Tab
ESC [ Pn L (A) Insert Line
ESC [ Pn M (A) Delete Line
ESC [ Pn @ (A) Insert Character
ESC [ Pn P (A) Delete Character
ESC [ Pn S Scroll Scrolling Region Up
ESC [ Pn T Scroll Scrolling Region Down
ESC [ Pn ^ same as above
ESC [ Ps ;...; Ps h Set Mode
ESC [ Ps ;...; Ps l Reset Mode
Ps = 4 (A) Insert Mode
20 (A) `Automatic Linefeed' Mode.
34 Normal Cursor Visibility
?1 (V) Application Cursor Keys
?3 (V) Change Terminal Width to 132 columns
?5 (V) Reverse Video
?6 (V) `Origin' Mode
?7 (V) `Wrap' Mode
?9 X10 mouse tracking
?25 (V) Visible Cursor
?1000 (V) VT200 mouse tracking
ESC [ 5 i (A) Start relay to printer (ANSI Media Copy)
ESC [ 4 i (A) Stop relay to printer (ANSI Media Copy)
ESC [ 8 ; Ph ; Pw t Resize the window to `Ph' lines and
`Pw' columns (SunView special)
ESC [ c Send VT100 Identification String
ESC [ x (V) Send Terminal Parameter Report
ESC [ > c Send Secondary Device Attributes String
ESC [ 6 n Send Cursor Position Report
File: screen.info, Node: Input Translation, Next: Digraph, Prev: Control Sequences, Up: Virtual Terminal
Input Translation
=================
In order to do a full VT100 emulation `screen' has to detect that a
sequence of characters in the input stream was generated by a keypress
on the user's keyboard and insert the VT100 style escape sequence.
`Screen' has a very flexible way of doing this by making it possible to
map arbitrary commands on arbitrary sequences of characters. For
standard VT100 emulation the command will always insert a string in the
input buffer of the window (see also command `stuff', *note Paste::).
Because the sequences generated by a keypress can change after a
reattach from a different terminal type, it is possible to bind
commands to the termcap name of the keys. `Screen' will insert the
correct binding after each reattach. See *Note Bindkey:: for further
details on the syntax and examples.
Here is the table of the default key bindings. (A) means that the
command is executed if the keyboard is switched into application mode.
Key name Termcap name Command
-----------------------------------------------------
Cursor up ku stuff \033[A
stuff \033OA (A)
Cursor down kd stuff \033[B
stuff \033OB (A)
Cursor right kr stuff \033[C
stuff \033OC (A)
Cursor left kl stuff \033[D
stuff \033OD (A)
Function key 0 k0 stuff \033[10~
Function key 1 k1 stuff \033OP
Function key 2 k2 stuff \033OQ
Function key 3 k3 stuff \033OR
Function key 4 k4 stuff \033OS
Function key 5 k5 stuff \033[15~
Function key 6 k6 stuff \033[17~
Function key 7 k7 stuff \033[18~
Function key 8 k8 stuff \033[19~
Function key 9 k9 stuff \033[20~
Function key 10 k; stuff \033[21~
Function key 11 F1 stuff \033[23~
Function key 12 F2 stuff \033[24~
Home kh stuff \033[1~
End kH stuff \033[4~
Insert kI stuff \033[2~
Delete kD stuff \033[3~
Page up kP stuff \033[5~
Page down kN stuff \033[6~
Keypad 0 f0 stuff 0
stuff \033Op (A)
Keypad 1 f1 stuff 1
stuff \033Oq (A)
Keypad 2 f2 stuff 2
stuff \033Or (A)
Keypad 3 f3 stuff 3
stuff \033Os (A)
Keypad 4 f4 stuff 4
stuff \033Ot (A)
Keypad 5 f5 stuff 5
stuff \033Ou (A)
Keypad 6 f6 stuff 6
stuff \033Ov (A)
Keypad 7 f7 stuff 7
stuff \033Ow (A)
Keypad 8 f8 stuff 8
stuff \033Ox (A)
Keypad 9 f9 stuff 9
stuff \033Oy (A)
Keypad + f+ stuff +
stuff \033Ok (A)
Keypad - f- stuff -
stuff \033Om (A)
Keypad * f* stuff *
stuff \033Oj (A)
Keypad / f/ stuff /
stuff \033Oo (A)
Keypad = fq stuff =
stuff \033OX (A)
Keypad . f. stuff .
stuff \033On (A)
Keypad , f, stuff ,
stuff \033Ol (A)
Keypad enter fe stuff \015
stuff \033OM (A)
File: screen.info, Node: Digraph, Next: Bell, Prev: Input Translation, Up: Virtual Terminal
Digraph
=======
- Command: digraph [preset]
(none)
This command prompts the user for a digraph sequence. The next two
characters typed are looked up in a builtin table and the
resulting character is inserted in the input stream. For example,
if the user enters `a"', an a-umlaut will be inserted. If the
first character entered is a 0 (zero), `screen' will treat the
following characters (up to three) as an octal number instead.
The optional argument PRESET is treated as user input, thus one
can create an "umlaut" key. For example the command `bindkey ^K
digraph '"'' enables the user to generate an a-umlaut by typing
`CTRL-K a'.
File: screen.info, Node: Bell, Next: Clear, Prev: Digraph, Up: Virtual Terminal
Bell
====
- Command: bell_msg [message]
(none)
When a bell character is sent to a background window, `screen'
displays a notification in the message line. The notification
message can be re-defined by this command. Each occurrence of `%'
in MESSAGE is replaced by the number of the window to which a bell
has been sent, and each occurrence of `^G' is replaced by the
definition for bell in your termcap (usually an audible bell).
The default message is
'Bell in window %n'
An empty message can be supplied to the `bell_msg' command to
suppress output of a message line (`bell_msg ""'). Without
parameter, the current message is shown.
- Command: vbell [state]
(`C-a C-g')
Sets or toggles the visual bell setting for the current window. If
`vbell' is switched to `on', but your terminal does not support a
visual bell, the visual bell message is displayed in the status
line when the bell character is received. Visual bell support of
a terminal is defined by the termcap variable `vb'. *Note Visual
Bell: (termcap)Bell, for more information on visual bells. The
equivalent terminfo capability is `flash'.
Per default, `vbell' is `off', thus the audible bell is used.
- Command: vbell_msg [message]
(none)
Sets the visual bell message. MESSAGE is printed to the status
line if the window receives a bell character (^G), `vbell' is set
to `on' and the terminal does not support a visual bell. The
default message is `Wuff, Wuff!!'. Without parameter, the current
message is shown.
- Command: vbellwait sec
(none)
Define a delay in seconds after each display of `screen' 's visual
bell message. The default is 1 second.
File: screen.info, Node: Clear, Next: Info, Prev: Bell, Up: Virtual Terminal
Clear
=====
- Command: clear
(`C-a C')
Clears the screen and saves its contents to the scrollback buffer.
File: screen.info, Node: Info, Next: Redisplay, Prev: Clear, Up: Virtual Terminal
Info
====
- Command: info
(`C-a i', `C-a C-i')
Uses the message line to display some information about the current
window: the cursor position in the form `(COLUMN,ROW)' starting
with `(1,1)', the terminal width and height plus the size of the
scrollback buffer in lines, like in `(80,24)+50', the current
state of window XON/XOFF flow control is shown like this (*note
Flow Control::):
+flow automatic flow control, currently on.
-flow automatic flow control, currently off.
+(+)flow flow control enabled. Agrees with automatic control.
-(+)flow flow control disabled. Disagrees with automatic control.
+(-)flow flow control enabled. Disagrees with automatic control.
-(-)flow flow control disabled. Agrees with automatic control.
The current line wrap setting (`+wrap' indicates enabled, `-wrap'
not) is also shown. The flags `ins', `org', `app', `log', `mon'
and `nored' are displayed when the window is in insert mode,
origin mode, application-keypad mode, has output logging, insert
mode, origin mode, application-keypad mode, output logging,
activity monitoring or partial redraw enabled.
The currently active character set (`G0', `G1', `G2', or `G3'),
and in square brackets the terminal character sets that are
currently designated as `G0' through `G3'. If the window is in
UTF-8 mode, the string `UTF-8' is shown instead. Additional modes
depending on the type of the window are displayed at the end of
the status line (*note Window Types::).
If the state machine of the terminal emulator is in a non-default
state, the info line is started with a string identifying the
current state.
For system information use `time'.
- Command: dinfo
(none)
Show what screen thinks about your terminal. Useful if you want to
know why features like color or the alternate charset don't work.
|