1EDITLINE(3) BSD Library Functions Manual EDITLINE(3)
2
4 editline, el_init, el_init_fd, el_end, el_reset, el_gets, el_wgets,
5 el_getc, el_wgetc, el_push, el_wpush, el_parse, el_wparse, el_set,
6 el_wset, el_get, el_wget, el_source, el_resize, el_cursor, el_line,
7 el_wline, el_insertstr, el_winsertstr, el_deletestr, el_wdeletestr,
8 history_init, history_winit, history_end, history_wend, history,
9 history_w, tok_init, tok_winit, tok_end, tok_wend, tok_reset, tok_wreset,
10 tok_line, tok_wline, tok_str, tok_wstr — line editor, history and tok‐
11 enization functions
12
14 Command Line Editor Library (libedit, -ledit)
15
17 #include <histedit.h>
18 EditLine *
20 el_init(const char *prog, FILE *fin, FILE *fout, FILE *ferr);
21 EditLine *
23 el_init_fd(const char *prog, FILE *fin, FILE *fout, FILE *ferr, int fdin,
24 int fdout, int fderr);
25 void
27 el_end(EditLine *e);
28 void
30 el_reset(EditLine *e);
31 const char *
33 el_gets(EditLine *e, int *count);
34 const wchar_t *
36 el_wgets(EditLine *e, int *count);
37 int
39 el_getc(EditLine *e, char *ch);
40 int
42 el_wgetc(EditLine *e, wchar_t *wc);
43 void
45 el_push(EditLine *e, const char *mbs);
46 void
48 el_wpush(EditLine *e, const wchar_t *wcs);
49 int
51 el_parse(EditLine *e, int argc, const char *argv[]);
52 int
54 el_wparse(EditLine *e, int argc, const wchar_t *argv[]);
55 int
57 el_set(EditLine *e, int op, ...);
58 int
60 el_wset(EditLine *e, int op, ...);
61 int
63 el_get(EditLine *e, int op, ...);
64 int
66 el_wget(EditLine *e, int op, ...);
67 int
69 el_source(EditLine *e, const char *file);
70 void
72 el_resize(EditLine *e);
73 int
75 el_cursor(EditLine *e, int count);
76 const LineInfo *
78 el_line(EditLine *e);
79 const LineInfoW *
81 el_wline(EditLine *e);
82 int
84 el_insertstr(EditLine *e, const char *str);
85 int
87 el_winsertstr(EditLine *e, const wchar_t *str);
88 void
90 el_deletestr(EditLine *e, int count);
91 void
93 el_wdeletestr(EditLine *e, int count);
94 History *
96 history_init(void);
97 HistoryW *
99 history_winit(void);
100 void
102 history_end(History *h);
103 void
105 history_wend(HistoryW *h);
106 int
108 history(History *h, HistEvent *ev, int op, ...);
109 int
111 history_w(HistoryW *h, HistEventW *ev, int op, ...);
112 Tokenizer *
114 tok_init(const char *IFS);
115 TokenizerW *
117 tok_winit(const wchar_t *IFS);
118 void
120 tok_end(Tokenizer *t);
121 void
123 tok_wend(TokenizerW *t);
124 void
126 tok_reset(Tokenizer *t);
127 void
129 tok_wreset(TokenizerW *t);
130 int
132 tok_line(Tokenizer *t, const LineInfo *li, int *argc,
133 const char **argv[], int *cursorc, int *cursoro);
134 int
136 tok_wline(TokenizerW *t, const LineInfoW *li, int *argc,
137 const wchar_t **argv[], int *cursorc, int *cursoro);
138 int
140 tok_str(Tokenizer *t, const char *str, int *argc, const char **argv[]);
141 int
143 tok_wstr(TokenizerW *t, const wchar_t *str, int *argc,
144 const wchar_t **argv[]);
145
147 The editline library provides generic line editing, history and tokeniza‐
148 tion functions, similar to those found in sh(1).
149 These functions are available in the libedit library (which needs the
151 libtermcap library). Programs should be linked with -ledit -ltermcap.
152 The editline library respects the LC_CTYPE locale set by the application
154 program and never uses setlocale(3) to change the locale.
155
157 The line editing functions use a common data structure, EditLine, which
158 is created by el_init() or el_init_fd() and freed by el_end().
159 The wide-character functions behave the same way as their narrow counter‐
161 parts.
162 The following functions are available:
164 el_init()
166 Initialize the line editor, and return a data structure to be used
167 by all other line editing functions, or NULL on failure. prog is
168 the name of the invoking program, used when reading the editrc(5)
169 file to determine which settings to use. fin, fout and ferr are
170 the input, output, and error streams (respectively) to use. In
171 this documentation, references to “the tty” are actually to this
172 input/output stream combination.
173 el_init_fd()
175 Like el_init() but allows specifying file descriptors for the
176 stdio(3) corresponding streams, in case those were created with
177 funopen(3).
178 el_end()
180 Clean up and finish with e, assumed to have been created with
181 el_init() or el_init_fd().
182 el_reset()
184 Reset the tty and the parser. This should be called after an error
185 which may have upset the tty's state.
186 el_gets()
188 Read a line from the tty. count is modified to contain the number
189 of characters read. Returns the line read if successful, or NULL
190 if no characters were read or if an error occurred. If an error
191 occurred, count is set to -1 and errno contains the error code that
192 caused it. The return value may not remain valid across calls to
193 el_gets() and must be copied if the data is to be retained.
194 el_wgetc()
196 Read a wide character from the tty, respecting the current locale,
197 or from the input queue described in editline(7) if that is not
198 empty, and store it in wc. If an invalid or incomplete character
199 is found, it is discarded, errno is set to EILSEQ, and the next
200 character is read and stored in wc. Returns 1 if a valid character
201 was read, 0 on end of file, or -1 on read(2) failure. In the lat‐
202 ter case, errno is set to indicate the error.
203 el_getc()
205 Read a wide character as described for el_wgetc() and return 0 on
206 end of file or -1 on failure. If the wide character can be repre‐
207 sented as a single-byte character, convert it with wctob(3), store
208 the result in ch, and return 1; otherwise, set errno to ERANGE and
209 return -1. In the C or POSIX locale, this simply reads a byte, but
210 for any other locale, including UTF-8, this is rarely useful.
211 el_wpush()
213 Push the wide character string wcs back onto the input queue de‐
214 scribed in editline(7). If the queue overflows, for example due to
215 a recursive macro, or if an error occurs, for example because wcs
216 is NULL or memory allocation fails, the function beeps at the user,
217 but does not report the problem to the caller.
218 el_push()
220 Use the current locale to convert the multibyte string mbs to a
221 wide character string, and pass the result to el_wpush().
222 el_parse()
224 Parses the argv array (which is argc elements in size) to execute
225 builtin editline commands. If the command is prefixed with “prog”:
226 then el_parse() will only execute the command if “prog” matches the
227 prog argument supplied to el_init(). The return value is -1 if the
228 command is unknown, 0 if there was no error or “prog” didn't match,
229 or 1 if the command returned an error. Refer to editrc(5) for more
230 information.
231 el_set()
233 Set editline parameters. op determines which parameter to set, and
234 each operation has its own parameter list. Returns 0 on success,
235 -1 on failure.
236 The following values for op are supported, along with the required
238 argument list:
239 EL_PROMPT, char *(*f)(EditLine *)
241 Define prompt printing function as f, which is to return a
242 string that contains the prompt.
243 EL_PROMPT_ESC, char *(*f)(EditLine *), char c
245 Same as EL_PROMPT, but the c argument indicates the
246 start/stop literal prompt character.
247 If a start/stop literal character is found in the prompt, the
249 character itself is not printed, but characters after it are
250 printed directly to the terminal without affecting the state
251 of the current line. A subsequent second start/stop literal
252 character ends this behavior. This is typically used to em‐
253 bed literal escape sequences that change the color/style of
254 the terminal in the prompt. Note that the literal escape
255 character cannot be the last character in the prompt, as the
256 escape sequence is attached to the next character in the
257 prompt. 0 unsets it.
258 EL_REFRESH
260 Re-display the current line on the next terminal line.
261 EL_RPROMPT, char *(*f)(EditLine *)
263 Define right side prompt printing function as f, which is to
264 return a string that contains the prompt.
265 EL_RPROMPT_ESC, char *(*f)(EditLine *), char c
267 Define the right prompt printing function but with a literal
268 escape character.
269 EL_TERMINAL, const char *type
271 Define terminal type of the tty to be type, or to TERM if
272 type is NULL.
273 EL_EDITOR, const char *mode
275 Set editing mode to mode, which must be one of “emacs” or
276 “vi”.
277 EL_SIGNAL, int flag
279 If flag is non-zero, editline will install its own signal
280 handler for the following signals when reading command input:
281 SIGCONT, SIGHUP, SIGINT, SIGQUIT, SIGSTOP, SIGTERM, SIGTSTP,
282 and SIGWINCH. Otherwise, the current signal handlers will be
283 used.
284 EL_BIND, const char *, ..., NULL
286 Perform the bind builtin command. Refer to editrc(5) for
287 more information.
288 EL_ECHOTC, const char *, ..., NULL
290 Perform the echotc builtin command. Refer to editrc(5) for
291 more information.
292 EL_SETTC, const char *, ..., NULL
294 Perform the settc builtin command. Refer to editrc(5) for
295 more information.
296 EL_SETTY, const char *, ..., NULL
298 Perform the setty builtin command. Refer to editrc(5) for
299 more information.
300 EL_TELLTC, const char *, ..., NULL
302 Perform the telltc builtin command. Refer to editrc(5) for
303 more information.
304 EL_ADDFN, const char *name, const char *help, unsigned char
306 (*func)(EditLine *e, int ch)
307 Add a user defined function, func(), referred to as name
308 which is invoked when a key which is bound to name is en‐
309 tered. help is a description of name. At invocation time,
310 ch is the key which caused the invocation. The return value
311 of func() should be one of:
312 CC_NORM Add a normal character.
314 CC_NEWLINE End of line was entered.
316 CC_EOF EOF was entered.
318 CC_ARGHACK Expecting further command input as arguments,
320 do nothing visually.
321 CC_REFRESH Refresh display.
323 CC_REFRESH_BEEP
325 Refresh display, and beep.
326 CC_CURSOR Cursor moved, so update and perform CC_REFRESH.
328 CC_REDISPLAY Redisplay entire input line. This is useful if
330 a key binding outputs extra information.
331 CC_ERROR An error occurred. Beep, and flush tty.
333 CC_FATAL Fatal error, reset tty to known state.
335 EL_HIST, History *(*func)(History *, int op, ...), const char *ptr
337 Defines which history function to use, which is usually
338 history(). ptr should be the value returned by
339 history_init().
340 EL_EDITMODE, int flag
342 If flag is non-zero, editing is enabled (the default). Note
343 that this is only an indication, and does not affect the op‐
344 eration of editline. At this time, it is the caller's re‐
345 sponsibility to check this (using el_get()) to determine if
346 editing should be enabled or not.
347 EL_UNBUFFERED, int flag
349 If flag is zero, unbuffered mode is disabled (the default).
350 In unbuffered mode, el_gets() will return immediately after
351 processing a single character.
352 EL_SAFEREAD, int flag
354 If the flag argument is non-zero, then editline attempts to
355 recover from read errors, ignoring the first interrrupted er‐
356 ror, and trying to reset the input file descriptor to reset
357 non-blocking I/O. This is disabled by default, and desirable
358 only when editline is used in shell-like applications.
359 EL_GETCFN, el_rfunc_t f
361 Whenever reading a character, use the function
362 int f(EditLine *e, wchar_t *wc)
363 which stores the character in wc and returns 1 on success, 0
364 on end of file, or -1 on I/O or encoding errors. Functions
365 internally using it include el_wgets(), el_wgetc(),
366 el_gets(), and el_getc(). Initially, a builtin function is
367 installed, and replacing it is discouraged because writing
368 such a function is very error prone. The builtin function
369 can be restored at any time by passing the special value
370 EL_BUILTIN_GETCFN instead of a function pointer.
371 EL_CLIENTDATA, void *data
373 Register data to be associated with this EditLine structure.
374 It can be retrieved with the corresponding el_get() call.
375 EL_SETFP, int fd, FILE *fp
377 Set the current editline file pointer for “input” fd = 0,
378 “output” fd = 1, or “error” fd = 2 from fp.
379 el_get()
381 Get editline parameters. op determines which parameter to retrieve
382 into result. Returns 0 if successful, -1 otherwise.
383 The following values for op are supported, along with actual type
385 of result:
386 EL_PROMPT, char *(*f)(EditLine *), char *c
388 Set f to a pointer to the function that displays the prompt.
389 If c is not NULL, set it to the start/stop literal prompt
390 character.
391 EL_RPROMPT, char *(*f)(EditLine *), char *c
393 Set f to a pointer to the function that displays the prompt.
394 If c is not NULL, set it to the start/stop literal prompt
395 character.
396 EL_EDITOR, const char **n
398 Set the name of the editor in n, which will be one of “emacs”
399 or “vi”.
400 EL_GETTC, const char *name, void *value
402 If name is a valid termcap(5) capability set value to the
403 current value of that capability.
404 EL_SIGNAL, int *s
406 Set s to non-zero if editline has installed private signal
407 handlers (see el_get() above).
408 EL_EDITMODE, int *c
410 Set c to non-zero if editing is enabled.
411 EL_GETCFN, el_rfunc_t *f
413 Set f to a pointer to the function that reads characters, or
414 to EL_BUILTIN_GETCFN if the builtin function is in use.
415 EL_CLIENTDATA, void **data
417 Set data to the previously registered client data set by an
418 el_set() call.
419 EL_UNBUFFERED, int *c
421 Set c to non-zero if unbuffered mode is enabled.
422 EL_SAFEREAD, int *c
424 Set c to non-zero if safe read is set.
425 EL_GETFP, int fd, FILE **fp
427 Set fp to the current editline file pointer for “input” fd =
428 0, “output” fd = 1, or “error” fd = 2.
429 el_source()
431 Initialize editline by reading the contents of file. el_parse() is
432 called for each line in file. If file is NULL, try $EDITRC and if
433 that is not set $HOME/.editrc. Refer to editrc(5) for details on
434 the format of file. el_source() returns 0 on success and -1 on er‐
435 ror.
436 el_resize()
438 Must be called if the terminal size changes. If EL_SIGNAL has been
439 set with el_set(), then this is done automatically. Otherwise,
440 it's the responsibility of the application to call el_resize() on
441 the appropriate occasions.
442 el_cursor()
444 Move the cursor to the right (if positive) or to the left (if nega‐
445 tive) count characters. Returns the resulting offset of the cursor
446 from the beginning of the line.
447 el_line()
449 Return the editing information for the current line in a LineInfo
450 structure, which is defined as follows:
451 typedef struct lineinfo {
453 const char *buffer; /* address of buffer */
454 const char *cursor; /* address of cursor */
455 const char *lastchar; /* address of last character */
456 } LineInfo;
457 buffer is not NUL terminated. This function may be called after
459 el_gets() to obtain the LineInfo structure pertaining to line re‐
460 turned by that function, and from within user defined functions
461 added with EL_ADDFN.
462 el_insertstr()
464 Insert str into the line at the cursor. Returns -1 if str is empty
465 or won't fit, and 0 otherwise.
466 el_deletestr()
468 Delete count characters before the cursor.
469
471 The history functions use a common data structure, History, which is cre‐
472 ated by history_init() and freed by history_end().
473 The following functions are available:
475 history_init()
477 Initialize the history list, and return a data structure to be used
478 by all other history list functions, or NULL on failure.
479 history_end()
481 Clean up and finish with h, assumed to have been created with
482 history_init().
483 history()
485 Perform operation op on the history list, with optional arguments
486 as needed by the operation. ev is changed accordingly to opera‐
487 tion. The following values for op are supported, along with the
488 required argument list:
489 H_SETSIZE, int size
491 Set size of history to size elements.
492 H_GETSIZE
494 Get number of events currently in history.
495 H_END
497 Cleans up and finishes with h, assumed to be created with
498 history_init().
499 H_CLEAR
501 Clear the history.
502 H_FUNC, void *ptr, history_gfun_t first, history_gfun_t next,
504 history_gfun_t last, history_gfun_t prev, history_gfun_t
505 curr, history_sfun_t set, history_vfun_t clear,
506 history_efun_t enter, history_efun_t add
507 Define functions to perform various history operations. ptr
508 is the argument given to a function when it's invoked.
509 H_FIRST
511 Return the first element in the history.
512 H_LAST
514 Return the last element in the history.
515 H_PREV
517 Return the previous element in the history. It is newer than
518 the current one.
519 H_NEXT
521 Return the next element in the history. It is older than the
522 current one.
523 H_CURR
525 Return the current element in the history.
526 H_SET, int position
528 Set the cursor to point to the requested element.
529 H_ADD, const char *str
531 Append str to the current element of the history, or perform
532 the H_ENTER operation with argument str if there is no cur‐
533 rent element.
534 H_APPEND, const char *str
536 Append str to the last new element of the history.
537 H_ENTER, const char *str
539 Add str as a new element to the history and, if necessary,
540 removing the oldest entry to keep the list to the created
541 size. If H_SETUNIQUE has been called with a non-zero argu‐
542 ment, the element will not be entered into the history if its
543 contents match the ones of the current history element. If
544 the element is entered history() returns 1; if it is ignored
545 as a duplicate returns 0. Finally history() returns -1 if an
546 error occurred.
547 H_PREV_STR, const char *str
549 Return the closest previous event that starts with str.
550 H_NEXT_STR, const char *str
552 Return the closest next event that starts with str.
553 H_PREV_EVENT, int e
555 Return the previous event numbered e.
556 H_NEXT_EVENT, int e
558 Return the next event numbered e.
559 H_LOAD, const char *file
561 Load the history list stored in file.
562 H_SAVE, const char *file
564 Save the history list to file.
565 H_SAVE_FP, FILE *fp
567 Save the history list to the opened FILE pointer fp.
568 H_NSAVE_FP, size_t n, FILE *fp
570 Save the last n history entries to the opened FILE pointer
571 fp.
572 H_SETUNIQUE, int unique
574 Set flag that adjacent identical event strings should not be
575 entered into the history.
576 H_GETUNIQUE
578 Retrieve the current setting if adjacent identical elements
579 should be entered into the history.
580 H_DEL, int e
582 Delete the event numbered e. This function is only provided
583 for readline compatibility. The caller is responsible for
584 free'ing the string in the returned HistEvent.
585 history() returns >= 0 if the operation op succeeds. Otherwise, -1
587 is returned and ev is updated to contain more details about the er‐
588 ror.
589
591 The tokenization functions use a common data structure, Tokenizer, which
592 is created by tok_init() and freed by tok_end().
593 The following functions are available:
595 tok_init()
597 Initialize the tokenizer, and return a data structure to be used by
598 all other tokenizer functions. IFS contains the Input Field Sepa‐
599 rators, which defaults to ⟨space⟩, ⟨tab⟩, and ⟨newline⟩ if NULL.
600 tok_end()
602 Clean up and finish with t, assumed to have been created with
603 tok_init().
604 tok_reset()
606 Reset the tokenizer state. Use after a line has been successfully
607 tokenized by tok_line() or tok_str() and before a new line is to be
608 tokenized.
609 tok_line()
611 Tokenize li, If successful, modify: argv to contain the words, argc
612 to contain the number of words, cursorc (if not NULL) to contain
613 the index of the word containing the cursor, and cursoro (if not
614 NULL) to contain the offset within argv[cursorc] of the cursor.
615 Returns 0 if successful, -1 for an internal error, 1 for an un‐
617 matched single quote, 2 for an unmatched double quote, and 3 for a
618 backslash quoted ⟨newline⟩. A positive exit code indicates that
619 another line should be read and tokenization attempted again.
620 tok_str()
622 A simpler form of tok_line(); str is a NUL terminated string to to‐
623 kenize.
624
626 sh(1), signal(3), termcap(3), editrc(5), termcap(5), editline(7)
627
629 The editline library first appeared in 4.4BSD. CC_REDISPLAY appeared in
630 NetBSD 1.3. CC_REFRESH_BEEP, EL_EDITMODE and the readline emulation ap‐
631 peared in NetBSD 1.4. EL_RPROMPT appeared in NetBSD 1.5.
632
634 The editline library was written by Christos Zoulas. Luke Mewburn wrote
635 this manual and implemented CC_REDISPLAY, CC_REFRESH_BEEP, EL_EDITMODE,
636 and EL_RPROMPT. Jaromir Dolecek implemented the readline emulation.
637 Johny Mattsson implemented wide-character support.
638
640 At this time, it is the responsibility of the caller to check the result
641 of the EL_EDITMODE operation of el_get() (after an el_source() or
642 el_parse()) to determine if editline should be used for further input.
643 I.e., EL_EDITMODE is purely an indication of the result of the most re‐
644 cent editrc(5) edit command.
645BSD August 15, 2021 BSD