aboutsummaryrefslogtreecommitdiff
path: root/readline/doc/readline.3
blob: 90cd9971e8e92abd8aecaf40fe4ea588af2449ac (plain)
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
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
.\"
.\" MAN PAGE COMMENTS to
.\"
.\"	Chet Ramey
.\"	Information Network Services
.\"	Case Western Reserve University
.\"	chet@ins.CWRU.Edu
.\"
.\"	Last Change: Tue Sep 13 12:07:26 EDT 2005
.\"
.TH READLINE 3 "2005 Sep 13" "GNU Readline 5.1-beta1"
.\"
.\" File Name macro.  This used to be `.PN', for Path Name,
.\" but Sun doesn't seem to like that very much.
.\"
.de FN
\fI\|\\$1\|\fP
..
.SH NAME
readline \- get a line from a user with editing
.SH SYNOPSIS
.LP
.nf
.ft B
#include <stdio.h>
#include <readline/readline.h>
#include <readline/history.h>
.ft
.fi
.LP
.nf
\fIchar *\fP
.br
\fBreadline\fP (\fIconst char *prompt\fP);
.fi
.SH COPYRIGHT
.if n Readline is Copyright (C) 1989\-2004 by the Free Software Foundation, Inc.
.if t Readline is Copyright \(co 1989\-2004 by the Free Software Foundation, Inc.
.SH DESCRIPTION
.LP
.B readline
will read a line from the terminal
and return it, using
.B prompt
as a prompt.  If 
.B prompt
is \fBNULL\fP or the empty string, no prompt is issued.
The line returned is allocated with
.IR malloc (3);
the caller must free it when finished.  The line returned
has the final newline removed, so only the text of the line
remains.
.LP
.B readline
offers editing capabilities while the user is entering the
line.
By default, the line editing commands
are similar to those of emacs.
A vi\-style line editing interface is also available.
.LP
This manual page describes only the most basic use of \fBreadline\fP.
Much more functionality is available; see
\fIThe GNU Readline Library\fP and \fIThe GNU History Library\fP
for additional information.
.SH RETURN VALUE
.LP
.B readline
returns the text of the line read.  A blank line
returns the empty string.  If
.B EOF
is encountered while reading a line, and the line is empty,
.B NULL
is returned.  If an
.B EOF
is read with a non\-empty line, it is
treated as a newline.
.SH NOTATION
.LP
An emacs-style notation is used to denote
keystrokes.  Control keys are denoted by C\-\fIkey\fR, e.g., C\-n
means Control\-N.  Similarly, 
.I meta
keys are denoted by M\-\fIkey\fR, so M\-x means Meta\-X.  (On keyboards
without a 
.I meta
key, M\-\fIx\fP means ESC \fIx\fP, i.e., press the Escape key
then the
.I x
key.  This makes ESC the \fImeta prefix\fP.
The combination M\-C\-\fIx\fP means ESC\-Control\-\fIx\fP,
or press the Escape key
then hold the Control key while pressing the
.I x
key.)
.PP
Readline commands may be given numeric
.IR arguments ,
which normally act as a repeat count.  Sometimes, however, it is the
sign of the argument that is significant.  Passing a negative argument
to a command that acts in the forward direction (e.g., \fBkill\-line\fP)
causes that command to act in a backward direction.  Commands whose
behavior with arguments deviates from this are noted.
.PP
When a command is described as \fIkilling\fP text, the text
deleted is saved for possible future retrieval
(\fIyanking\fP).  The killed text is saved in a
\fIkill ring\fP.  Consecutive kills cause the text to be
accumulated into one unit, which can be yanked all at once. 
Commands which do not kill text separate the chunks of text
on the kill ring.
.SH INITIALIZATION FILE
.LP
Readline is customized by putting commands in an initialization
file (the \fIinputrc\fP file).
The name of this file is taken from the value of the
.B INPUTRC
environment variable.  If that variable is unset, the default is
.IR ~/.inputrc .
When a program which uses the readline library starts up, the
init file is read, and the key bindings and variables are set.
There are only a few basic constructs allowed in the
readline init file.  Blank lines are ignored.
Lines beginning with a \fB#\fP are comments.
Lines beginning with a \fB$\fP indicate conditional constructs.
Other lines denote key bindings and variable settings.
Each program using this library may add its own commands
and bindings.
.PP
For example, placing
.RS
.PP
M\-Control\-u: universal\-argument
.RE
or
.RS
C\-Meta\-u: universal\-argument
.RE
.sp
into the 
.I inputrc
would make M\-C\-u execute the readline command
.IR universal\-argument .
.PP
The following symbolic character names are recognized while
processing key bindings:
.IR DEL ,
.IR ESC ,
.IR ESCAPE ,
.IR LFD ,
.IR NEWLINE ,
.IR RET ,
.IR RETURN ,
.IR RUBOUT ,
.IR SPACE ,
.IR SPC ,
and
.IR TAB .
.PP
In addition to command names, readline allows keys to be bound
to a string that is inserted when the key is pressed (a \fImacro\fP).
.PP
.SS Key Bindings
.PP
The syntax for controlling key bindings in the
.I inputrc
file is simple.  All that is required is the name of the
command or the text of a macro and a key sequence to which
it should be bound. The name may be specified in one of two ways:
as a symbolic key name, possibly with \fIMeta\-\fP or \fIControl\-\fP
prefixes, or as a key sequence.
.PP
When using the form \fBkeyname\fP:\^\fIfunction-name\fP or \fImacro\fP,
.I keyname
is the name of a key spelled out in English.  For example:
.sp
.RS
Control\-u: universal\-argument
.br
Meta\-Rubout: backward\-kill\-word
.br
Control\-o: "> output"
.RE
.LP
In the above example,
.I C\-u
is bound to the function
.BR universal\-argument ,
.I M-DEL
is bound to the function
.BR backward\-kill\-word ,
and
.I C\-o
is bound to run the macro
expressed on the right hand side (that is, to insert the text
.if t \f(CW> output\fP
.if n ``> output''
into the line).
.PP
In the second form, \fB"keyseq"\fP:\^\fIfunction\-name\fP or \fImacro\fP,
.B keyseq
differs from
.B keyname
above in that strings denoting
an entire key sequence may be specified by placing the sequence
within double quotes.  Some GNU Emacs style key escapes can be
used, as in the following example, but the symbolic character names
are not recognized.
.sp
.RS
"\eC\-u": universal\-argument
.br
"\eC\-x\eC\-r": re\-read\-init\-file
.br
"\ee[11~": "Function Key 1"
.RE
.PP
In this example,
.I C-u
is again bound to the function
.BR universal\-argument .
.I "C-x C-r"
is bound to the function
.BR re\-read\-init\-file ,
and 
.I "ESC [ 1 1 ~"
is bound to insert the text
.if t \f(CWFunction Key 1\fP.
.if n ``Function Key 1''.
.PP
The full set of GNU Emacs style escape sequences available when specifying
key sequences is
.RS
.PD 0
.TP
.B \eC\-
control prefix
.TP
.B \eM\-
meta prefix
.TP
.B \ee
an escape character
.TP
.B \e\e
backslash
.TP
.B \e"
literal ", a double quote
.TP
.B \e'
literal ', a single quote
.RE
.PD
.PP
In addition to the GNU Emacs style escape sequences, a second
set of backslash escapes is available:
.RS
.PD 0
.TP
.B \ea
alert (bell)
.TP
.B \eb
backspace
.TP
.B \ed
delete
.TP
.B \ef
form feed
.TP
.B \en
newline
.TP
.B \er
carriage return
.TP
.B \et
horizontal tab
.TP
.B \ev
vertical tab
.TP
.B \e\fInnn\fP
the eight-bit character whose value is the octal value \fInnn\fP
(one to three digits)
.TP
.B \ex\fIHH\fP
the eight-bit character whose value is the hexadecimal value \fIHH\fP
(one or two hex digits)
.RE
.PD
.PP
When entering the text of a macro, single or double quotes should
be used to indicate a macro definition.  Unquoted text
is assumed to be a function name.
In the macro body, the backslash escapes described above are expanded.
Backslash will quote any other character in the macro text,
including " and '.
.PP
.B Bash
allows the current readline key bindings to be displayed or modified
with the
.B bind
builtin command.  The editing mode may be switched during interactive
use by using the
.B \-o
option to the
.B set
builtin command.  Other programs using this library provide
similar mechanisms.  The
.I inputrc
file may be edited and re-read if a program does not provide
any other means to incorporate new bindings.
.SS Variables
.PP
Readline has variables that can be used to further customize its
behavior.  A variable may be set in the
.I inputrc
file with a statement of the form
.RS
.PP
\fBset\fP \fIvariable\-name\fP \fIvalue\fP
.RE
.PP
Except where noted, readline variables can take the values
.B On
or
.B Off
(without regard to case).
Unrecognized variable names are ignored.
When a variable value is read, empty or null values, "on" (case-insensitive),
and "1" are equivalent to \fBOn\fP.  All other values are equivalent to
\fBOff\fP.
The variables and their default values are:
.PP
.PD 0
.TP
.B bell\-style (audible)
Controls what happens when readline wants to ring the terminal bell.
If set to \fBnone\fP, readline never rings the bell.  If set to
\fBvisible\fP, readline uses a visible bell if one is available.
If set to \fBaudible\fP, readline attempts to ring the terminal's bell.
.TP
.B bind\-tty\-special\-chars (On)
If set to \fBOn\fP, readline attempts to bind the control characters  
treated specially by the kernel's terminal driver to their readline
equivalents.
.TP
.B comment\-begin (``#'')
The string that is inserted in \fBvi\fP mode when the
.B insert\-comment
command is executed.
This command is bound to
.B M\-#
in emacs mode and to
.B #
in vi command mode.
.TP 
.B completion\-ignore\-case (Off)
If set to \fBOn\fP, readline performs filename matching and completion
in a case\-insensitive fashion.
.TP
.B completion\-query\-items (100)
This determines when the user is queried about viewing
the number of possible completions
generated by the \fBpossible\-completions\fP command.
It may be set to any integer value greater than or equal to
zero.  If the number of possible completions is greater than
or equal to the value of this variable, the user is asked whether
or not he wishes to view them; otherwise they are simply listed
on the terminal.  A negative value causes readline to never ask.
.TP
.B convert\-meta (On)
If set to \fBOn\fP, readline will convert characters with the
eighth bit set to an ASCII key sequence
by stripping the eighth bit and prefixing it with an
escape character (in effect, using escape as the \fImeta prefix\fP).
.TP
.B disable\-completion (Off)
If set to \fBOn\fP, readline will inhibit word completion.  Completion 
characters will be inserted into the line as if they had been
mapped to \fBself-insert\fP.
.TP
.B editing\-mode (emacs)
Controls whether readline begins with a set of key bindings similar
to emacs or vi.
.B editing\-mode
can be set to either
.B emacs
or
.BR vi .
.TP
.B enable\-keypad (Off)
When set to \fBOn\fP, readline will try to enable the application
keypad when it is called.  Some systems need this to enable the
arrow keys.
.TP
.B expand\-tilde (Off)
If set to \fBon\fP, tilde expansion is performed when readline
attempts word completion.
.TP
.B history\-preserve\-point (Off)
If set to \fBon\fP, the history code attempts to place point at the 
same location on each history line retrieved with \fBprevious-history\fP 
or \fBnext-history\fP.
.TP
.B horizontal\-scroll\-mode (Off)
When set to \fBOn\fP, makes readline use a single line for display,
scrolling the input horizontally on a single screen line when it
becomes longer than the screen width rather than wrapping to a new line.
.TP
.B input\-meta (Off)
If set to \fBOn\fP, readline will enable eight-bit input (that is,
it will not clear the eighth bit in the characters it reads),
regardless of what the terminal claims it can support.  The name
.B meta\-flag
is a synonym for this variable.
.TP
.B isearch\-terminators (``C\-[ C\-J'')
The string of characters that should terminate an incremental
search without subsequently executing the character as a command.
If this variable has not been given a value, the characters
\fIESC\fP and \fIC\-J\fP will terminate an incremental search.
.TP
.B keymap (emacs)
Set the current readline keymap.  The set of legal keymap names is
\fIemacs, emacs-standard, emacs-meta, emacs-ctlx, vi, vi-move,
vi-command\fP, and
.IR vi-insert .
\fIvi\fP is equivalent to \fIvi-command\fP; \fIemacs\fP is
equivalent to \fIemacs-standard\fP.  The default value is
.IR emacs .
The value of
.B editing\-mode
also affects the default keymap.
.TP
.B mark\-directories (On)
If set to \fBOn\fP, completed directory names have a slash
appended.
.TP
.B mark\-modified\-lines (Off)
If set to \fBOn\fP, history lines that have been modified are displayed
with a preceding asterisk (\fB*\fP).
.TP
.B mark\-symlinked\-directories (Off)
If set to \fBOn\fP, completed names which are symbolic links to directories
have a slash appended (subject to the value of
\fBmark\-directories\fP).
.TP
.B match\-hidden\-files (On)
This variable, when set to \fBOn\fP, causes readline to match files whose 
names begin with a `.' (hidden files) when performing filename     
completion, unless the leading `.' is     
supplied by the user in the filename to be completed.
.TP
.B output\-meta (Off)
If set to \fBOn\fP, readline will display characters with the
eighth bit set directly rather than as a meta-prefixed escape
sequence.
.TP
.B page\-completions (On)
If set to \fBOn\fP, readline uses an internal \fImore\fP-like pager
to display a screenful of possible completions at a time.
.TP
.B print\-completions\-horizontally (Off)
If set to \fBOn\fP, readline will display completions with matches
sorted horizontally in alphabetical order, rather than down the screen.
.TP
.B show\-all\-if\-ambiguous (Off)
This alters the default behavior of the completion functions.  If
set to
.BR on ,
words which have more than one possible completion cause the
matches to be listed immediately instead of ringing the bell.
.TP
.B show\-all\-if\-unmodified (Off)
This alters the default behavior of the completion functions in
a fashion similar to \fBshow\-all\-if\-ambiguous\fP.
If set to
.BR on , 
words which have more than one possible completion without any
possible partial completion (the possible completions don't share 
a common prefix) cause the matches to be listed immediately instead
of ringing the bell.
.TP
.B visible\-stats (Off)
If set to \fBOn\fP, a character denoting a file's type as reported  
by \fIstat\fP(2) is appended to the filename when listing possible
completions.
.PD
.SS Conditional Constructs
.PP
Readline implements a facility similar in spirit to the conditional
compilation features of the C preprocessor which allows key
bindings and variable settings to be performed as the result
of tests.  There are four parser directives used.
.IP \fB$if\fP
The 
.B $if
construct allows bindings to be made based on the
editing mode, the terminal being used, or the application using
readline.  The text of the test extends to the end of the line;
no characters are required to isolate it.
.RS
.IP \fBmode\fP
The \fBmode=\fP form of the \fB$if\fP directive is used to test
whether readline is in emacs or vi mode.
This may be used in conjunction
with the \fBset keymap\fP command, for instance, to set bindings in
the \fIemacs-standard\fP and \fIemacs-ctlx\fP keymaps only if
readline is starting out in emacs mode.
.IP \fBterm\fP
The \fBterm=\fP form may be used to include terminal-specific
key bindings, perhaps to bind the key sequences output by the
terminal's function keys.  The word on the right side of the
.B =
is tested against the full name of the terminal and the portion
of the terminal name before the first \fB\-\fP.  This allows
.I sun
to match both
.I sun
and
.IR sun\-cmd ,
for instance.
.IP \fBapplication\fP
The \fBapplication\fP construct is used to include
application-specific settings.  Each program using the readline
library sets the \fIapplication name\fP, and an initialization
file can test for a particular value.
This could be used to bind key sequences to functions useful for
a specific program.  For instance, the following command adds a
key sequence that quotes the current or previous word in Bash:
.sp 1
.RS
.nf
\fB$if\fP Bash
# Quote the current or previous word
"\eC-xq": "\eeb\e"\eef\e""
\fB$endif\fP
.fi
.RE
.RE
.IP \fB$endif\fP
This command, as seen in the previous example, terminates an
\fB$if\fP command.
.IP \fB$else\fP
Commands in this branch of the \fB$if\fP directive are executed if
the test fails.
.IP \fB$include\fP
This directive takes a single filename as an argument and reads commands
and bindings from that file.  For example, the following directive
would read \fI/etc/inputrc\fP:
.sp 1
.RS
.nf
\fB$include\fP \^ \fI/etc/inputrc\fP
.fi 
.RE
.SH SEARCHING
.PP
Readline provides commands for searching through the command history
for lines containing a specified string.
There are two search modes:
.I incremental
and
.IR non-incremental .
.PP
Incremental searches begin before the user has finished typing the
search string.
As each character of the search string is typed, readline displays
the next entry from the history matching the string typed so far.
An incremental search requires only as many characters as needed to
find the desired history entry.
To search backward in the history for a particular string, type
\fBC\-r\fP.  Typing \fBC\-s\fP searches forward through the history.
The characters present in the value of the \fBisearch-terminators\fP
variable are used to terminate an incremental search.
If that variable has not been assigned a value the \fIEscape\fP and
\fBC\-J\fP characters will terminate an incremental search.
\fBC\-G\fP will abort an incremental search and restore the original
line.
When the search is terminated, the history entry containing the
search string becomes the current line.
.PP
To find other matching entries in the history list, type \fBC\-s\fP or
\fBC\-r\fP as appropriate.
This will search backward or forward in the history for the next
line matching the search string typed so far.
Any other key sequence bound to a readline command will terminate
the search and execute that command.
For instance, a newline will terminate the search and accept
the line, thereby executing the command from the history list.
A movement command will terminate the search, make the last line found
the current line, and begin editing.
.PP
Non-incremental searches read the entire search string before starting
to search for matching history lines.  The search string may be
typed by the user or be part of the contents of the current line.
.SH EDITING COMMANDS
.PP
The following is a list of the names of the commands and the default
key sequences to which they are bound.
Command names without an accompanying key sequence are unbound by default.
.PP
In the following descriptions, \fIpoint\fP refers to the current cursor
position, and \fImark\fP refers to a cursor position saved by the
\fBset\-mark\fP command.
The text between the point and mark is referred to as the \fIregion\fP.
.SS Commands for Moving
.PP
.PD 0
.TP
.B beginning\-of\-line (C\-a)
Move to the start of the current line.
.TP
.B end\-of\-line (C\-e)
Move to the end of the line.
.TP
.B forward\-char (C\-f)
Move forward a character.
.TP
.B backward\-char (C\-b)
Move back a character.
.TP
.B forward\-word (M\-f)
Move forward to the end of the next word.  Words are composed of
alphanumeric characters (letters and digits).
.TP
.B backward\-word (M\-b)
Move back to the start of the current or previous word.  Words are
composed of alphanumeric characters (letters and digits).
.TP
.B clear\-screen (C\-l)
Clear the screen leaving the current line at the top of the screen.
With an argument, refresh the current line without clearing the
screen.
.TP
.B redraw\-current\-line
Refresh the current line.
.PD
.SS Commands for Manipulating the History
.PP
.PD 0
.TP
.B accept\-line (Newline, Return)
Accept the line regardless of where the cursor is.
If this line is
non-empty, it may be added to the history list for future recall with
\fBadd_history()\fP.
If the line is a modified history line, the history line is restored to its original state.
.TP
.B previous\-history (C\-p)
Fetch the previous command from the history list, moving back in
the list.
.TP
.B next\-history (C\-n)
Fetch the next command from the history list, moving forward in the
list.
.TP
.B beginning\-of\-history (M\-<)
Move to the first line in the history.
.TP
.B end\-of\-history (M\->)
Move to the end of the input history, i.e., the line currently being
entered.
.TP
.B reverse\-search\-history (C\-r)
Search backward starting at the current line and moving `up' through
the history as necessary.  This is an incremental search.
.TP
.B forward\-search\-history (C\-s)
Search forward starting at the current line and moving `down' through
the history as necessary.  This is an incremental search.
.TP
.B non\-incremental\-reverse\-search\-history (M\-p)
Search backward through the history starting at the current line
using a non-incremental search for a string supplied by the user.
.TP
.B non\-incremental\-forward\-search\-history (M\-n)
Search forward through the history using a non-incremental search
for a string supplied by the user.
.TP
.B history\-search\-forward
Search forward through the history for the string of characters
between the start of the current line and the current cursor
position (the \fIpoint\fP).
This is a non-incremental search.
.TP
.B history\-search\-backward
Search backward through the history for the string of characters
between the start of the current line and the point.
This is a non-incremental search.
.TP
.B yank\-nth\-arg (M\-C\-y)
Insert the first argument to the previous command (usually
the second word on the previous line) at point.
With an argument
.IR n ,
insert the \fIn\fPth word from the previous command (the words
in the previous command begin with word 0).  A negative argument
inserts the \fIn\fPth word from the end of the previous command.
Once the argument \fIn\fP is computed, the argument is extracted
as if the "!\fIn\fP" history expansion had been specified.
.TP
.B
yank\-last\-arg (M\-.\^, M\-_\^)
Insert the last argument to the previous command (the last word of
the previous history entry).  With an argument,
behave exactly like \fByank\-nth\-arg\fP.
Successive calls to \fByank\-last\-arg\fP move back through the history
list, inserting the last argument of each line in turn.
The history expansion facilities are used to extract the last argument,
as if the "!$" history expansion had been specified.
.PD
.SS Commands for Changing Text
.PP
.PD 0
.TP
.B delete\-char (C\-d)
Delete the character at point.  If point is at the
beginning of the line, there are no characters in the line, and
the last character typed was not bound to \fBdelete\-char\fP, then return
.SM
.BR EOF .
.TP
.B backward\-delete\-char (Rubout)
Delete the character behind the cursor.  When given a numeric argument,
save the deleted text on the kill ring.
.TP
.B forward\-backward\-delete\-char   
Delete the character under the cursor, unless the cursor is at the
end of the line, in which case the character behind the cursor is
deleted.
.TP
.B quoted\-insert (C\-q, C\-v)
Add the next character that you type to the line verbatim.  This is
how to insert characters like \fBC\-q\fP, for example.
.TP
.B tab\-insert (M-TAB)
Insert a tab character.
.TP
.B self\-insert (a,\ b,\ A,\ 1,\ !,\ ...)
Insert the character typed.
.TP
.B transpose\-chars (C\-t)
Drag the character before point forward over the character at point,
moving point forward as well.
If point is at the end of the line, then this transposes
the two characters before point.
Negative arguments have no effect.
.TP
.B transpose\-words (M\-t)
Drag the word before point past the word after point,
moving point over that word as well.
If point is at the end of the line, this transposes
the last two words on the line.
.TP
.B upcase\-word (M\-u)
Uppercase the current (or following) word.  With a negative argument,
uppercase the previous word, but do not move point.
.TP
.B downcase\-word (M\-l)
Lowercase the current (or following) word.  With a negative argument,
lowercase the previous word, but do not move point.
.TP
.B capitalize\-word (M\-c)
Capitalize the current (or following) word.  With a negative argument,
capitalize the previous word, but do not move point.
.TP
.B overwrite\-mode
Toggle overwrite mode.  With an explicit positive numeric argument,
switches to overwrite mode.  With an explicit non-positive numeric
argument, switches to insert mode.  This command affects only
\fBemacs\fP mode; \fBvi\fP mode does overwrite differently.
Each call to \fIreadline()\fP starts in insert mode.
In overwrite mode, characters bound to \fBself\-insert\fP replace   
the text at point rather than pushing the text to the right.
Characters bound to \fBbackward\-delete\-char\fP replace the character
before point with a space.  By default, this command is unbound.
.PD
.SS Killing and Yanking
.PP
.PD 0
.TP
.B kill\-line (C\-k)
Kill the text from point to the end of the line.
.TP
.B backward\-kill\-line (C\-x Rubout)
Kill backward to the beginning of the line.
.TP
.B unix\-line\-discard (C\-u)
Kill backward from point to the beginning of the line.
The killed text is saved on the kill-ring.
.\" There is no real difference between this and backward-kill-line
.TP
.B kill\-whole\-line
Kill all characters on the current line, no matter where point is.
.TP
.B kill\-word  (M\-d)
Kill from point the end of the current word, or if between
words, to the end of the next word.  Word boundaries are the same as
those used by \fBforward\-word\fP.
.TP
.B backward\-kill\-word (M\-Rubout)
Kill the word behind point.
Word boundaries are the same as those used by \fBbackward\-word\fP.
.TP
.B unix\-word\-rubout (C\-w)
Kill the word behind point, using white space as a word boundary.
The killed text is saved on the kill-ring.
.TP
.B unix\-filename\-rubout
Kill the word behind point, using white space and the slash character
as the word boundaries.
The killed text is saved on the kill-ring.
.TP
.B delete\-horizontal\-space (M\-\e)
Delete all spaces and tabs around point.
.TP
.B kill\-region
Kill the text between the point and \fImark\fP (saved cursor position).
This text is referred to as the \fIregion\fP.
.TP
.B copy\-region\-as\-kill
Copy the text in the region to the kill buffer.
.TP
.B copy\-backward\-word
Copy the word before point to the kill buffer.
The word boundaries are the same as \fBbackward\-word\fP.
.TP
.B copy\-forward\-word
Copy the word following point to the kill buffer.
The word boundaries are the same as \fBforward\-word\fP.
.TP
.B yank (C\-y)
Yank the top of the kill ring into the buffer at point.
.TP
.B yank\-pop (M\-y)
Rotate the kill ring, and yank the new top.  Only works following
.B yank
or
.BR yank\-pop .
.PD
.SS Numeric Arguments
.PP
.PD 0
.TP
.B digit\-argument (M\-0, M\-1, ..., M\-\-)
Add this digit to the argument already accumulating, or start a new
argument.  M\-\- starts a negative argument.
.TP
.B universal\-argument
This is another way to specify an argument.
If this command is followed by one or more digits, optionally with a
leading minus sign, those digits define the argument.
If the command is followed by digits, executing
.B universal\-argument
again ends the numeric argument, but is otherwise ignored.
As a special case, if this command is immediately followed by a
character that is neither a digit or minus sign, the argument count
for the next command is multiplied by four.
The argument count is initially one, so executing this function the
first time makes the argument count four, a second time makes the
argument count sixteen, and so on.
.PD
.SS Completing
.PP
.PD 0
.TP
.B complete (TAB)
Attempt to perform completion on the text before point.
The actual completion performed is application-specific.
.BR Bash ,
for instance, attempts completion treating the text as a variable
(if the text begins with \fB$\fP), username (if the text begins with
\fB~\fP), hostname (if the text begins with \fB@\fP), or
command (including aliases and functions) in turn.  If none
of these produces a match, filename completion is attempted.
.BR Gdb ,
on the other hand,
allows completion of program functions and variables, and
only attempts filename completion under certain circumstances.
.TP
.B possible\-completions (M\-?)
List the possible completions of the text before point.
.TP
.B insert\-completions (M\-*)
Insert all completions of the text before point
that would have been generated by
\fBpossible\-completions\fP.
.TP
.B menu\-complete
Similar to \fBcomplete\fP, but replaces the word to be completed
with a single match from the list of possible completions.
Repeated execution of \fBmenu\-complete\fP steps through the list
of possible completions, inserting each match in turn.
At the end of the list of completions, the bell is rung
(subject to the setting of \fBbell\-style\fP)
and the original text is restored.
An argument of \fIn\fP moves \fIn\fP positions forward in the list
of matches; a negative argument may be used to move backward 
through the list.
This command is intended to be bound to \fBTAB\fP, but is unbound
by default.
.TP
.B delete\-char\-or\-list
Deletes the character under the cursor if not at the beginning or
end of the line (like \fBdelete-char\fP).
If at the end of the line, behaves identically to
\fBpossible-completions\fP.
.PD
.SS Keyboard Macros
.PP
.PD 0
.TP
.B start\-kbd\-macro (C\-x (\^)
Begin saving the characters typed into the current keyboard macro.
.TP
.B end\-kbd\-macro (C\-x )\^)
Stop saving the characters typed into the current keyboard macro
and store the definition.
.TP
.B call\-last\-kbd\-macro (C\-x e)
Re-execute the last keyboard macro defined, by making the characters
in the macro appear as if typed at the keyboard.
.PD
.SS Miscellaneous
.PP
.PD 0
.TP
.B re\-read\-init\-file (C\-x C\-r)
Read in the contents of the \fIinputrc\fP file, and incorporate
any bindings or variable assignments found there.
.TP
.B abort (C\-g)
Abort the current editing command and
ring the terminal's bell (subject to the setting of
.BR bell\-style ).
.TP
.B do\-uppercase\-version (M\-a, M\-b, M\-\fIx\fP, ...)
If the metafied character \fIx\fP is lowercase, run the command
that is bound to the corresponding uppercase character.
.TP
.B prefix\-meta (ESC)
Metafy the next character typed.
.SM
.B ESC
.B f
is equivalent to
.BR Meta\-f .
.TP
.B undo (C\-_, C\-x C\-u)
Incremental undo, separately remembered for each line.
.TP
.B revert\-line (M\-r)
Undo all changes made to this line.  This is like executing the
.B undo
command enough times to return the line to its initial state.
.TP
.B tilde\-expand (M\-&)
Perform tilde expansion on the current word.
.TP
.B set\-mark (C\-@, M\-<space>)
Set the mark to the point.  If a
numeric argument is supplied, the mark is set to that position.
.TP
.B exchange\-point\-and\-mark (C\-x C\-x)
Swap the point with the mark.  The current cursor position is set to
the saved position, and the old cursor position is saved as the mark.
.TP
.B character\-search (C\-])
A character is read and point is moved to the next occurrence of that
character.  A negative count searches for previous occurrences.
.TP
.B character\-search\-backward (M\-C\-])
A character is read and point is moved to the previous occurrence of that
character.  A negative count searches for subsequent occurrences.
.TP
.B insert\-comment (M\-#)
Without a numeric argument, the value of the readline
.B comment\-begin
variable is inserted at the beginning of the current line.
If a numeric argument is supplied, this command acts as a toggle:  if
the characters at the beginning of the line do not match the value   
of \fBcomment\-begin\fP, the value is inserted, otherwise             
the characters in \fBcomment-begin\fP are deleted from the beginning of
the line.
In either case, the line is accepted as if a newline had been typed.
The default value of
.B comment\-begin
makes the current line a shell comment.
If a numeric argument causes the comment character to be removed, the line
will be executed by the shell.
.TP
.B dump\-functions
Print all of the functions and their key bindings to the
readline output stream.  If a numeric argument is supplied,
the output is formatted in such a way that it can be made part
of an \fIinputrc\fP file.
.TP
.B dump\-variables
Print all of the settable variables and their values to the
readline output stream.  If a numeric argument is supplied,
the output is formatted in such a way that it can be made part
of an \fIinputrc\fP file.
.TP
.B dump\-macros
Print all of the readline key sequences bound to macros and the
strings they output.  If a numeric argument is supplied,
the output is formatted in such a way that it can be made part
of an \fIinputrc\fP file.
.TP
.B emacs\-editing\-mode (C\-e)
When in
.B vi
command mode, this causes a switch to
.B emacs
editing mode.
.TP
.B vi\-editing\-mode (M\-C\-j)
When in
.B emacs
editing mode, this causes a switch to
.B vi
editing mode.
.PD
.SH DEFAULT KEY BINDINGS
.LP
The following is a list of the default emacs and vi bindings.
Characters with the eighth bit set are written as M\-<character>, and
are referred to as
.I metafied
characters.
The printable ASCII characters not mentioned in the list of emacs
standard bindings are bound to the
.B self\-insert
function, which just inserts the given character into the input line.
In vi insertion mode, all characters not specifically mentioned are
bound to
.BR self\-insert .
Characters assigned to signal generation by
.IR stty (1)
or the terminal driver, such as C-Z or C-C,
retain that function.
Upper and lower case metafied characters are bound to the same function in
the emacs mode meta keymap.
The remaining characters are unbound, which causes readline
to ring the bell (subject to the setting of the
.B bell\-style
variable).
.SS Emacs Mode
.RS +.6i
.nf
.ta 2.5i
.sp
Emacs Standard bindings
.sp
"C-@"  set-mark
"C-A"  beginning-of-line
"C-B"  backward-char
"C-D"  delete-char
"C-E"  end-of-line
"C-F"  forward-char
"C-G"  abort
"C-H"  backward-delete-char
"C-I"  complete
"C-J"  accept-line
"C-K"  kill-line
"C-L"  clear-screen
"C-M"  accept-line
"C-N"  next-history
"C-P"  previous-history
"C-Q"  quoted-insert
"C-R"  reverse-search-history
"C-S"  forward-search-history
"C-T"  transpose-chars
"C-U"  unix-line-discard
"C-V"  quoted-insert
"C-W"  unix-word-rubout
"C-Y"  yank
"C-]"  character-search
"C-_"  undo
"\^ " to "/"  self-insert
"0"  to "9"  self-insert
":"  to "~"  self-insert
"C-?"  backward-delete-char
.PP
Emacs Meta bindings
.sp
"M-C-G"  abort
"M-C-H"  backward-kill-word
"M-C-I"  tab-insert
"M-C-J"  vi-editing-mode
"M-C-M"  vi-editing-mode
"M-C-R"  revert-line
"M-C-Y"  yank-nth-arg
"M-C-["  complete
"M-C-]"  character-search-backward
"M-space"  set-mark
"M-#"  insert-comment
"M-&"  tilde-expand
"M-*"  insert-completions
"M--"  digit-argument
"M-."  yank-last-arg
"M-0"  digit-argument
"M-1"  digit-argument
"M-2"  digit-argument
"M-3"  digit-argument
"M-4"  digit-argument
"M-5"  digit-argument
"M-6"  digit-argument
"M-7"  digit-argument
"M-8"  digit-argument
"M-9"  digit-argument
"M-<"  beginning-of-history
"M-="  possible-completions
"M->"  end-of-history
"M-?"  possible-completions
"M-B"  backward-word
"M-C"  capitalize-word
"M-D"  kill-word
"M-F"  forward-word
"M-L"  downcase-word
"M-N"  non-incremental-forward-search-history
"M-P"  non-incremental-reverse-search-history
"M-R"  revert-line
"M-T"  transpose-words
"M-U"  upcase-word
"M-Y"  yank-pop
"M-\e"  delete-horizontal-space
"M-~"  tilde-expand
"M-C-?"  backward-kill-word
"M-_"  yank-last-arg
.PP
Emacs Control-X bindings
.sp
"C-XC-G"  abort
"C-XC-R"  re-read-init-file
"C-XC-U"  undo
"C-XC-X"  exchange-point-and-mark
"C-X("  start-kbd-macro
"C-X)"  end-kbd-macro
"C-XE"  call-last-kbd-macro
"C-XC-?"  backward-kill-line
.sp
.RE
.SS VI Mode bindings
.RS +.6i
.nf
.ta 2.5i
.sp
.PP
VI Insert Mode functions
.sp
"C-D"  vi-eof-maybe
"C-H"  backward-delete-char
"C-I"  complete
"C-J"  accept-line
"C-M"  accept-line
"C-R"  reverse-search-history
"C-S"  forward-search-history
"C-T"  transpose-chars
"C-U"  unix-line-discard
"C-V"  quoted-insert
"C-W"  unix-word-rubout
"C-Y"  yank
"C-["  vi-movement-mode
"C-_"  undo
"\^ " to "~"  self-insert
"C-?"  backward-delete-char
.PP
VI Command Mode functions
.sp
"C-D"  vi-eof-maybe
"C-E"  emacs-editing-mode
"C-G"  abort
"C-H"  backward-char
"C-J"  accept-line
"C-K"  kill-line
"C-L"  clear-screen
"C-M"  accept-line
"C-N"  next-history
"C-P"  previous-history
"C-Q"  quoted-insert
"C-R"  reverse-search-history
"C-S"  forward-search-history
"C-T"  transpose-chars
"C-U"  unix-line-discard
"C-V"  quoted-insert
"C-W"  unix-word-rubout
"C-Y"  yank
"C-_"  vi-undo
"\^ "  forward-char
"#"  insert-comment
"$"  end-of-line
"%"  vi-match
"&"  vi-tilde-expand
"*"  vi-complete
"+"  next-history
","  vi-char-search
"-"  previous-history
"."  vi-redo
"/"  vi-search
"0"  beginning-of-line
"1" to "9"  vi-arg-digit
";"  vi-char-search
"="  vi-complete
"?"  vi-search
"A"  vi-append-eol
"B"  vi-prev-word
"C"  vi-change-to
"D"  vi-delete-to
"E"  vi-end-word
"F"  vi-char-search
"G"  vi-fetch-history
"I"  vi-insert-beg
"N"  vi-search-again
"P"  vi-put
"R"  vi-replace
"S"  vi-subst
"T"  vi-char-search
"U"  revert-line
"W"  vi-next-word
"X"  backward-delete-char
"Y"  vi-yank-to
"\e"  vi-complete
"^"  vi-first-print
"_"  vi-yank-arg
"`"  vi-goto-mark
"a"  vi-append-mode
"b"  vi-prev-word
"c"  vi-change-to
"d"  vi-delete-to
"e"  vi-end-word
"f"  vi-char-search
"h"  backward-char
"i"  vi-insertion-mode
"j"  next-history
"k"  prev-history
"l"  forward-char
"m"  vi-set-mark
"n"  vi-search-again
"p"  vi-put
"r"  vi-change-char
"s"  vi-subst
"t"  vi-char-search
"u"  vi-undo
"w"  vi-next-word
"x"  vi-delete
"y"  vi-yank-to
"|"  vi-column
"~"  vi-change-case
.RE
.SH "SEE ALSO"
.PD 0
.TP
\fIThe Gnu Readline Library\fP, Brian Fox and Chet Ramey
.TP
\fIThe Gnu History Library\fP, Brian Fox and Chet Ramey
.TP
\fIbash\fP(1)
.PD
.SH FILES
.PD 0
.TP
.FN ~/.inputrc
Individual \fBreadline\fP initialization file
.PD
.SH AUTHORS
Brian Fox, Free Software Foundation
.br
bfox@gnu.org
.PP
Chet Ramey, Case Western Reserve University
.br
chet@ins.CWRU.Edu
.SH BUG REPORTS
If you find a bug in
.B readline,
you should report it.  But first, you should
make sure that it really is a bug, and that it appears in the latest
version of the
.B readline
library that you have.
.PP
Once you have determined that a bug actually exists, mail a
bug report to \fIbug\-readline\fP@\fIgnu.org\fP.
If you have a fix, you are welcome to mail that
as well!  Suggestions and `philosophical' bug reports may be mailed
to \fPbug-readline\fP@\fIgnu.org\fP or posted to the Usenet
newsgroup
.BR gnu.bash.bug .
.PP
Comments and bug reports concerning
this manual page should be directed to
.IR chet@ins.CWRU.Edu .
.SH BUGS
.PP
It's too big and too slow.