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1 | @ignore |
2 | This file documents the user interface to the GNU History library. | |
3 | ||
9255ee31 | 4 | Copyright (C) 1988-2002 Free Software Foundation, Inc. |
d60d9f65 SS |
5 | Authored by Brian Fox and Chet Ramey. |
6 | ||
7 | Permission is granted to make and distribute verbatim copies of this manual | |
8 | provided the copyright notice and this permission notice are preserved on | |
9 | all copies. | |
10 | ||
11 | Permission is granted to process this file through Tex and print the | |
12 | results, provided the printed document carries copying permission notice | |
13 | identical to this one except for the removal of this paragraph (this | |
14 | paragraph not being relevant to the printed manual). | |
15 | ||
16 | Permission is granted to copy and distribute modified versions of this | |
17 | manual under the conditions for verbatim copying, provided also that the | |
18 | GNU Copyright statement is available to the distributee, and provided that | |
19 | the entire resulting derived work is distributed under the terms of a | |
20 | permission notice identical to this one. | |
21 | ||
22 | Permission is granted to copy and distribute translations of this manual | |
23 | into another language, under the above conditions for modified versions. | |
24 | @end ignore | |
25 | ||
26 | @node Programming with GNU History | |
27 | @chapter Programming with GNU History | |
28 | ||
29 | This chapter describes how to interface programs that you write | |
9255ee31 | 30 | with the @sc{gnu} History Library. |
d60d9f65 | 31 | It should be considered a technical guide. |
9255ee31 | 32 | For information on the interactive use of @sc{gnu} History, @pxref{Using |
d60d9f65 SS |
33 | History Interactively}. |
34 | ||
35 | @menu | |
36 | * Introduction to History:: What is the GNU History library for? | |
37 | * History Storage:: How information is stored. | |
38 | * History Functions:: Functions that you can use. | |
39 | * History Variables:: Variables that control behaviour. | |
40 | * History Programming Example:: Example of using the GNU History Library. | |
41 | @end menu | |
42 | ||
43 | @node Introduction to History | |
44 | @section Introduction to History | |
45 | ||
9255ee31 EZ |
46 | Many programs read input from the user a line at a time. The @sc{gnu} |
47 | History library is able to keep track of those lines, associate arbitrary | |
48 | data with each line, and utilize information from previous lines in | |
49 | composing new ones. | |
d60d9f65 SS |
50 | |
51 | The programmer using the History library has available functions | |
52 | for remembering lines on a history list, associating arbitrary data | |
53 | with a line, removing lines from the list, searching through the list | |
54 | for a line containing an arbitrary text string, and referencing any line | |
55 | in the list directly. In addition, a history @dfn{expansion} function | |
56 | is available which provides for a consistent user interface across | |
57 | different programs. | |
58 | ||
59 | The user using programs written with the History library has the | |
60 | benefit of a consistent user interface with a set of well-known | |
61 | commands for manipulating the text of previous lines and using that text | |
62 | in new commands. The basic history manipulation commands are similar to | |
63 | the history substitution provided by @code{csh}. | |
64 | ||
65 | If the programmer desires, he can use the Readline library, which | |
66 | includes some history manipulation by default, and has the added | |
67 | advantage of command line editing. | |
68 | ||
1b17e766 EZ |
69 | Before declaring any functions using any functionality the History |
70 | library provides in other code, an application writer should include | |
71 | the file @code{<readline/history.h>} in any file that uses the | |
72 | History library's features. It supplies extern declarations for all | |
73 | of the library's public functions and variables, and declares all of | |
74 | the public data structures. | |
75 | ||
d60d9f65 SS |
76 | @node History Storage |
77 | @section History Storage | |
78 | ||
79 | The history list is an array of history entries. A history entry is | |
80 | declared as follows: | |
81 | ||
82 | @example | |
9255ee31 EZ |
83 | typedef void *histdata_t; |
84 | ||
d60d9f65 SS |
85 | typedef struct _hist_entry @{ |
86 | char *line; | |
9255ee31 | 87 | histdata_t data; |
d60d9f65 SS |
88 | @} HIST_ENTRY; |
89 | @end example | |
90 | ||
91 | The history list itself might therefore be declared as | |
92 | ||
93 | @example | |
94 | HIST_ENTRY **the_history_list; | |
95 | @end example | |
96 | ||
97 | The state of the History library is encapsulated into a single structure: | |
98 | ||
99 | @example | |
9255ee31 EZ |
100 | /* |
101 | * A structure used to pass around the current state of the history. | |
102 | */ | |
d60d9f65 | 103 | typedef struct _hist_state @{ |
9255ee31 EZ |
104 | HIST_ENTRY **entries; /* Pointer to the entries themselves. */ |
105 | int offset; /* The location pointer within this array. */ | |
106 | int length; /* Number of elements within this array. */ | |
107 | int size; /* Number of slots allocated to this array. */ | |
d60d9f65 SS |
108 | int flags; |
109 | @} HISTORY_STATE; | |
110 | @end example | |
111 | ||
112 | If the flags member includes @code{HS_STIFLED}, the history has been | |
113 | stifled. | |
114 | ||
115 | @node History Functions | |
116 | @section History Functions | |
117 | ||
118 | This section describes the calling sequence for the various functions | |
9255ee31 | 119 | exported by the @sc{gnu} History library. |
d60d9f65 SS |
120 | |
121 | @menu | |
122 | * Initializing History and State Management:: Functions to call when you | |
123 | want to use history in a | |
124 | program. | |
125 | * History List Management:: Functions used to manage the list | |
126 | of history entries. | |
127 | * Information About the History List:: Functions returning information about | |
128 | the history list. | |
129 | * Moving Around the History List:: Functions used to change the position | |
130 | in the history list. | |
131 | * Searching the History List:: Functions to search the history list | |
132 | for entries containing a string. | |
133 | * Managing the History File:: Functions that read and write a file | |
134 | containing the history list. | |
135 | * History Expansion:: Functions to perform csh-like history | |
136 | expansion. | |
137 | @end menu | |
138 | ||
139 | @node Initializing History and State Management | |
140 | @subsection Initializing History and State Management | |
141 | ||
142 | This section describes functions used to initialize and manage | |
143 | the state of the History library when you want to use the history | |
144 | functions in your program. | |
145 | ||
9255ee31 | 146 | @deftypefun void using_history (void) |
d60d9f65 SS |
147 | Begin a session in which the history functions might be used. This |
148 | initializes the interactive variables. | |
149 | @end deftypefun | |
150 | ||
9255ee31 | 151 | @deftypefun {HISTORY_STATE *} history_get_history_state (void) |
d60d9f65 SS |
152 | Return a structure describing the current state of the input history. |
153 | @end deftypefun | |
154 | ||
155 | @deftypefun void history_set_history_state (HISTORY_STATE *state) | |
156 | Set the state of the history list according to @var{state}. | |
157 | @end deftypefun | |
158 | ||
159 | @node History List Management | |
160 | @subsection History List Management | |
161 | ||
162 | These functions manage individual entries on the history list, or set | |
163 | parameters managing the list itself. | |
164 | ||
9255ee31 | 165 | @deftypefun void add_history (const char *string) |
d60d9f65 SS |
166 | Place @var{string} at the end of the history list. The associated data |
167 | field (if any) is set to @code{NULL}. | |
168 | @end deftypefun | |
169 | ||
170 | @deftypefun {HIST_ENTRY *} remove_history (int which) | |
171 | Remove history entry at offset @var{which} from the history. The | |
172 | removed element is returned so you can free the line, data, | |
173 | and containing structure. | |
174 | @end deftypefun | |
175 | ||
9255ee31 | 176 | @deftypefun {HIST_ENTRY *} replace_history_entry (int which, const char *line, histdata_t data) |
d60d9f65 SS |
177 | Make the history entry at offset @var{which} have @var{line} and @var{data}. |
178 | This returns the old entry so you can dispose of the data. In the case | |
179 | of an invalid @var{which}, a @code{NULL} pointer is returned. | |
180 | @end deftypefun | |
181 | ||
9255ee31 | 182 | @deftypefun void clear_history (void) |
d60d9f65 SS |
183 | Clear the history list by deleting all the entries. |
184 | @end deftypefun | |
185 | ||
186 | @deftypefun void stifle_history (int max) | |
187 | Stifle the history list, remembering only the last @var{max} entries. | |
188 | @end deftypefun | |
189 | ||
9255ee31 EZ |
190 | @deftypefun int unstifle_history (void) |
191 | Stop stifling the history. This returns the previously-set | |
192 | maximum number of history entries (as set by @code{stifle_history()}). | |
193 | The value is positive if the history was | |
d60d9f65 SS |
194 | stifled, negative if it wasn't. |
195 | @end deftypefun | |
196 | ||
9255ee31 | 197 | @deftypefun int history_is_stifled (void) |
d60d9f65 SS |
198 | Returns non-zero if the history is stifled, zero if it is not. |
199 | @end deftypefun | |
200 | ||
201 | @node Information About the History List | |
202 | @subsection Information About the History List | |
203 | ||
204 | These functions return information about the entire history list or | |
205 | individual list entries. | |
206 | ||
9255ee31 EZ |
207 | @deftypefun {HIST_ENTRY **} history_list (void) |
208 | Return a @code{NULL} terminated array of @code{HIST_ENTRY *} which is the | |
d60d9f65 SS |
209 | current input history. Element 0 of this list is the beginning of time. |
210 | If there is no history, return @code{NULL}. | |
211 | @end deftypefun | |
212 | ||
9255ee31 | 213 | @deftypefun int where_history (void) |
d60d9f65 SS |
214 | Returns the offset of the current history element. |
215 | @end deftypefun | |
216 | ||
9255ee31 | 217 | @deftypefun {HIST_ENTRY *} current_history (void) |
d60d9f65 | 218 | Return the history entry at the current position, as determined by |
9255ee31 | 219 | @code{where_history()}. If there is no entry there, return a @code{NULL} |
d60d9f65 SS |
220 | pointer. |
221 | @end deftypefun | |
222 | ||
223 | @deftypefun {HIST_ENTRY *} history_get (int offset) | |
224 | Return the history entry at position @var{offset}, starting from | |
9255ee31 EZ |
225 | @code{history_base} (@pxref{History Variables}). |
226 | If there is no entry there, or if @var{offset} | |
d60d9f65 SS |
227 | is greater than the history length, return a @code{NULL} pointer. |
228 | @end deftypefun | |
229 | ||
9255ee31 | 230 | @deftypefun int history_total_bytes (void) |
d60d9f65 SS |
231 | Return the number of bytes that the primary history entries are using. |
232 | This function returns the sum of the lengths of all the lines in the | |
233 | history. | |
234 | @end deftypefun | |
235 | ||
236 | @node Moving Around the History List | |
237 | @subsection Moving Around the History List | |
238 | ||
239 | These functions allow the current index into the history list to be | |
240 | set or changed. | |
241 | ||
242 | @deftypefun int history_set_pos (int pos) | |
9255ee31 | 243 | Set the current history offset to @var{pos}, an absolute index |
d60d9f65 | 244 | into the list. |
9255ee31 EZ |
245 | Returns 1 on success, 0 if @var{pos} is less than zero or greater |
246 | than the number of history entries. | |
d60d9f65 SS |
247 | @end deftypefun |
248 | ||
9255ee31 | 249 | @deftypefun {HIST_ENTRY *} previous_history (void) |
d60d9f65 SS |
250 | Back up the current history offset to the previous history entry, and |
251 | return a pointer to that entry. If there is no previous entry, return | |
252 | a @code{NULL} pointer. | |
253 | @end deftypefun | |
254 | ||
9255ee31 | 255 | @deftypefun {HIST_ENTRY *} next_history (void) |
d60d9f65 SS |
256 | Move the current history offset forward to the next history entry, and |
257 | return the a pointer to that entry. If there is no next entry, return | |
258 | a @code{NULL} pointer. | |
259 | @end deftypefun | |
260 | ||
261 | @node Searching the History List | |
262 | @subsection Searching the History List | |
263 | @cindex History Searching | |
264 | ||
265 | These functions allow searching of the history list for entries containing | |
266 | a specific string. Searching may be performed both forward and backward | |
267 | from the current history position. The search may be @dfn{anchored}, | |
268 | meaning that the string must match at the beginning of the history entry. | |
269 | @cindex anchored search | |
270 | ||
9255ee31 EZ |
271 | @deftypefun int history_search (const char *string, int direction) |
272 | Search the history for @var{string}, starting at the current history offset. | |
273 | If @var{direction} is less than 0, then the search is through | |
274 | previous entries, otherwise through subsequent entries. | |
275 | If @var{string} is found, then | |
d60d9f65 SS |
276 | the current history index is set to that history entry, and the value |
277 | returned is the offset in the line of the entry where | |
278 | @var{string} was found. Otherwise, nothing is changed, and a -1 is | |
279 | returned. | |
280 | @end deftypefun | |
281 | ||
9255ee31 | 282 | @deftypefun int history_search_prefix (const char *string, int direction) |
d60d9f65 SS |
283 | Search the history for @var{string}, starting at the current history |
284 | offset. The search is anchored: matching lines must begin with | |
9255ee31 EZ |
285 | @var{string}. If @var{direction} is less than 0, then the search is |
286 | through previous entries, otherwise through subsequent entries. | |
287 | If @var{string} is found, then the | |
d60d9f65 SS |
288 | current history index is set to that entry, and the return value is 0. |
289 | Otherwise, nothing is changed, and a -1 is returned. | |
290 | @end deftypefun | |
291 | ||
9255ee31 | 292 | @deftypefun int history_search_pos (const char *string, int direction, int pos) |
d60d9f65 SS |
293 | Search for @var{string} in the history list, starting at @var{pos}, an |
294 | absolute index into the list. If @var{direction} is negative, the search | |
295 | proceeds backward from @var{pos}, otherwise forward. Returns the absolute | |
296 | index of the history element where @var{string} was found, or -1 otherwise. | |
297 | @end deftypefun | |
298 | ||
299 | @node Managing the History File | |
300 | @subsection Managing the History File | |
301 | ||
302 | The History library can read the history from and write it to a file. | |
303 | This section documents the functions for managing a history file. | |
304 | ||
9255ee31 EZ |
305 | @deftypefun int read_history (const char *filename) |
306 | Add the contents of @var{filename} to the history list, a line at a time. | |
307 | If @var{filename} is @code{NULL}, then read from @file{~/.history}. | |
308 | Returns 0 if successful, or @code{errno} if not. | |
d60d9f65 SS |
309 | @end deftypefun |
310 | ||
9255ee31 | 311 | @deftypefun int read_history_range (const char *filename, int from, int to) |
d60d9f65 | 312 | Read a range of lines from @var{filename}, adding them to the history list. |
9255ee31 EZ |
313 | Start reading at line @var{from} and end at @var{to}. |
314 | If @var{from} is zero, start at the beginning. If @var{to} is less than | |
d60d9f65 SS |
315 | @var{from}, then read until the end of the file. If @var{filename} is |
316 | @code{NULL}, then read from @file{~/.history}. Returns 0 if successful, | |
317 | or @code{errno} if not. | |
318 | @end deftypefun | |
319 | ||
9255ee31 | 320 | @deftypefun int write_history (const char *filename) |
d60d9f65 | 321 | Write the current history to @var{filename}, overwriting @var{filename} |
9255ee31 EZ |
322 | if necessary. |
323 | If @var{filename} is @code{NULL}, then write the history list to | |
324 | @file{~/.history}. | |
325 | Returns 0 on success, or @code{errno} on a read or write error. | |
d60d9f65 SS |
326 | @end deftypefun |
327 | ||
9255ee31 | 328 | @deftypefun int append_history (int nelements, const char *filename) |
d60d9f65 | 329 | Append the last @var{nelements} of the history list to @var{filename}. |
9255ee31 EZ |
330 | If @var{filename} is @code{NULL}, then append to @file{~/.history}. |
331 | Returns 0 on success, or @code{errno} on a read or write error. | |
d60d9f65 SS |
332 | @end deftypefun |
333 | ||
9255ee31 | 334 | @deftypefun int history_truncate_file (const char *filename, int nlines) |
d60d9f65 SS |
335 | Truncate the history file @var{filename}, leaving only the last |
336 | @var{nlines} lines. | |
9255ee31 EZ |
337 | If @var{filename} is @code{NULL}, then @file{~/.history} is truncated. |
338 | Returns 0 on success, or @code{errno} on failure. | |
d60d9f65 SS |
339 | @end deftypefun |
340 | ||
341 | @node History Expansion | |
342 | @subsection History Expansion | |
343 | ||
9255ee31 | 344 | These functions implement history expansion. |
d60d9f65 SS |
345 | |
346 | @deftypefun int history_expand (char *string, char **output) | |
347 | Expand @var{string}, placing the result into @var{output}, a pointer | |
348 | to a string (@pxref{History Interaction}). Returns: | |
349 | @table @code | |
350 | @item 0 | |
351 | If no expansions took place (or, if the only change in | |
9255ee31 | 352 | the text was the removal of escape characters preceding the history expansion |
d60d9f65 SS |
353 | character); |
354 | @item 1 | |
355 | if expansions did take place; | |
356 | @item -1 | |
357 | if there was an error in expansion; | |
358 | @item 2 | |
1b17e766 | 359 | if the returned line should be displayed, but not executed, |
d60d9f65 SS |
360 | as with the @code{:p} modifier (@pxref{Modifiers}). |
361 | @end table | |
362 | ||
363 | If an error ocurred in expansion, then @var{output} contains a descriptive | |
364 | error message. | |
365 | @end deftypefun | |
366 | ||
9255ee31 | 367 | @deftypefun {char *} get_history_event (const char *string, int *cindex, int qchar) |
d60d9f65 SS |
368 | Returns the text of the history event beginning at @var{string} + |
369 | @var{*cindex}. @var{*cindex} is modified to point to after the event | |
370 | specifier. At function entry, @var{cindex} points to the index into | |
371 | @var{string} where the history event specification begins. @var{qchar} | |
372 | is a character that is allowed to end the event specification in addition | |
373 | to the ``normal'' terminating characters. | |
374 | @end deftypefun | |
375 | ||
9255ee31 | 376 | @deftypefun {char **} history_tokenize (const char *string) |
d60d9f65 | 377 | Return an array of tokens parsed out of @var{string}, much as the |
9255ee31 EZ |
378 | shell might. The tokens are split on the characters in the |
379 | @var{history_word_delimiters} variable, | |
380 | and shell quoting conventions are obeyed. | |
381 | @end deftypefun | |
382 | ||
383 | @deftypefun {char *} history_arg_extract (int first, int last, const char *string) | |
384 | Extract a string segment consisting of the @var{first} through @var{last} | |
385 | arguments present in @var{string}. Arguments are split using | |
386 | @code{history_tokenize}. | |
d60d9f65 SS |
387 | @end deftypefun |
388 | ||
389 | @node History Variables | |
390 | @section History Variables | |
391 | ||
9255ee31 EZ |
392 | This section describes the externally-visible variables exported by |
393 | the @sc{gnu} History Library. | |
d60d9f65 SS |
394 | |
395 | @deftypevar int history_base | |
396 | The logical offset of the first entry in the history list. | |
397 | @end deftypevar | |
398 | ||
399 | @deftypevar int history_length | |
400 | The number of entries currently stored in the history list. | |
401 | @end deftypevar | |
402 | ||
9255ee31 | 403 | @deftypevar int history_max_entries |
d60d9f65 | 404 | The maximum number of history entries. This must be changed using |
9255ee31 | 405 | @code{stifle_history()}. |
d60d9f65 SS |
406 | @end deftypevar |
407 | ||
408 | @deftypevar char history_expansion_char | |
9255ee31 EZ |
409 | The character that introduces a history event. The default is @samp{!}. |
410 | Setting this to 0 inhibits history expansion. | |
d60d9f65 SS |
411 | @end deftypevar |
412 | ||
413 | @deftypevar char history_subst_char | |
414 | The character that invokes word substitution if found at the start of | |
415 | a line. The default is @samp{^}. | |
416 | @end deftypevar | |
417 | ||
418 | @deftypevar char history_comment_char | |
419 | During tokenization, if this character is seen as the first character | |
420 | of a word, then it and all subsequent characters up to a newline are | |
421 | ignored, suppressing history expansion for the remainder of the line. | |
422 | This is disabled by default. | |
423 | @end deftypevar | |
424 | ||
9255ee31 EZ |
425 | @deftypevar {char *} history_word_delimiters |
426 | The characters that separate tokens for @code{history_tokenize()}. | |
427 | The default value is @code{" \t\n()<>;&|"}. | |
428 | @end deftypevar | |
429 | ||
d60d9f65 SS |
430 | @deftypevar {char *} history_no_expand_chars |
431 | The list of characters which inhibit history expansion if found immediately | |
9255ee31 EZ |
432 | following @var{history_expansion_char}. The default is space, tab, newline, |
433 | carriage return, and @samp{=}. | |
d60d9f65 SS |
434 | @end deftypevar |
435 | ||
436 | @deftypevar {char *} history_search_delimiter_chars | |
437 | The list of additional characters which can delimit a history search | |
9255ee31 | 438 | string, in addition to space, TAB, @samp{:} and @samp{?} in the case of |
d60d9f65 SS |
439 | a substring search. The default is empty. |
440 | @end deftypevar | |
441 | ||
442 | @deftypevar int history_quotes_inhibit_expansion | |
443 | If non-zero, single-quoted words are not scanned for the history expansion | |
444 | character. The default value is 0. | |
445 | @end deftypevar | |
446 | ||
9255ee31 | 447 | @deftypevar {rl_linebuf_func_t *} history_inhibit_expansion_function |
d60d9f65 | 448 | This should be set to the address of a function that takes two arguments: |
9255ee31 EZ |
449 | a @code{char *} (@var{string}) |
450 | and an @code{int} index into that string (@var{i}). | |
d60d9f65 SS |
451 | It should return a non-zero value if the history expansion starting at |
452 | @var{string[i]} should not be performed; zero if the expansion should | |
453 | be done. | |
454 | It is intended for use by applications like Bash that use the history | |
455 | expansion character for additional purposes. | |
9255ee31 | 456 | By default, this variable is set to @code{NULL}. |
d60d9f65 SS |
457 | @end deftypevar |
458 | ||
459 | @node History Programming Example | |
460 | @section History Programming Example | |
461 | ||
9255ee31 | 462 | The following program demonstrates simple use of the @sc{gnu} History Library. |
d60d9f65 SS |
463 | |
464 | @smallexample | |
9255ee31 EZ |
465 | #include <stdio.h> |
466 | #include <readline/history.h> | |
467 | ||
468 | main (argc, argv) | |
469 | int argc; | |
470 | char **argv; | |
d60d9f65 SS |
471 | @{ |
472 | char line[1024], *t; | |
473 | int len, done = 0; | |
474 | ||
475 | line[0] = 0; | |
476 | ||
477 | using_history (); | |
478 | while (!done) | |
479 | @{ | |
480 | printf ("history$ "); | |
481 | fflush (stdout); | |
482 | t = fgets (line, sizeof (line) - 1, stdin); | |
483 | if (t && *t) | |
484 | @{ | |
485 | len = strlen (t); | |
486 | if (t[len - 1] == '\n') | |
487 | t[len - 1] = '\0'; | |
488 | @} | |
489 | ||
490 | if (!t) | |
491 | strcpy (line, "quit"); | |
492 | ||
493 | if (line[0]) | |
494 | @{ | |
495 | char *expansion; | |
496 | int result; | |
497 | ||
498 | result = history_expand (line, &expansion); | |
499 | if (result) | |
500 | fprintf (stderr, "%s\n", expansion); | |
501 | ||
502 | if (result < 0 || result == 2) | |
503 | @{ | |
504 | free (expansion); | |
505 | continue; | |
506 | @} | |
507 | ||
508 | add_history (expansion); | |
509 | strncpy (line, expansion, sizeof (line) - 1); | |
510 | free (expansion); | |
511 | @} | |
512 | ||
513 | if (strcmp (line, "quit") == 0) | |
514 | done = 1; | |
515 | else if (strcmp (line, "save") == 0) | |
516 | write_history ("history_file"); | |
517 | else if (strcmp (line, "read") == 0) | |
518 | read_history ("history_file"); | |
519 | else if (strcmp (line, "list") == 0) | |
520 | @{ | |
521 | register HIST_ENTRY **the_list; | |
522 | register int i; | |
523 | ||
524 | the_list = history_list (); | |
525 | if (the_list) | |
526 | for (i = 0; the_list[i]; i++) | |
527 | printf ("%d: %s\n", i + history_base, the_list[i]->line); | |
528 | @} | |
529 | else if (strncmp (line, "delete", 6) == 0) | |
530 | @{ | |
531 | int which; | |
532 | if ((sscanf (line + 6, "%d", &which)) == 1) | |
533 | @{ | |
534 | HIST_ENTRY *entry = remove_history (which); | |
535 | if (!entry) | |
536 | fprintf (stderr, "No such entry %d\n", which); | |
537 | else | |
538 | @{ | |
539 | free (entry->line); | |
540 | free (entry); | |
541 | @} | |
542 | @} | |
543 | else | |
544 | @{ | |
545 | fprintf (stderr, "non-numeric arg given to `delete'\n"); | |
546 | @} | |
547 | @} | |
548 | @} | |
549 | @} | |
550 | @end smallexample |