xref: /openbsd/lib/libedit/editline.3 (revision 09467b48)
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30.Dd $Mdocdate: May 22 2016 $
31.Dt EDITLINE 3
32.Os
33.Sh NAME
34.Nm editline ,
35.Nm el_init ,
36.Nm el_end ,
37.Nm el_reset ,
38.Nm el_gets ,
39.Nm el_wgets ,
40.Nm el_getc ,
41.Nm el_wgetc ,
42.Nm el_push ,
43.Nm el_wpush ,
44.Nm el_parse ,
45.Nm el_wparse ,
46.Nm el_set ,
47.Nm el_wset ,
48.Nm el_get ,
49.Nm el_wget ,
50.Nm el_source ,
51.Nm el_resize ,
52.Nm el_line ,
53.Nm el_wline ,
54.Nm el_insertstr ,
55.Nm el_winsertstr ,
56.Nm el_deletestr ,
57.Nm el_wdeletestr ,
58.Nm history_init ,
59.Nm history_winit ,
60.Nm history_end ,
61.Nm history_wend ,
62.Nm history ,
63.Nm history_w ,
64.Nm tok_init ,
65.Nm tok_winit ,
66.Nm tok_end ,
67.Nm tok_wend ,
68.Nm tok_reset ,
69.Nm tok_wreset ,
70.Nm tok_line ,
71.Nm tok_wline ,
72.Nm tok_str ,
73.Nm tok_wstr
74.Nd line editor, history and tokenization functions
75.Sh SYNOPSIS
76.In histedit.h
77.Ft EditLine *
78.Fn el_init "const char *prog" "FILE *fin" "FILE *fout" "FILE *ferr"
79.Ft void
80.Fn el_end "EditLine *e"
81.Ft void
82.Fn el_reset "EditLine *e"
83.Ft const char *
84.Fn el_gets "EditLine *e" "int *count"
85.Ft const wchar_t *
86.Fn el_wgets "EditLine *e" "int *count"
87.Ft int
88.Fn el_getc "EditLine *e" "char *ch"
89.Ft int
90.Fn el_wgetc "EditLine *e" "wchar_t *wc"
91.Ft void
92.Fn el_push "EditLine *e" "const char *mbs"
93.Ft void
94.Fn el_wpush "EditLine *e" "const wchar_t *wcs"
95.Ft int
96.Fn el_parse "EditLine *e" "int argc" "const char *argv[]"
97.Ft int
98.Fn el_wparse "EditLine *e" "int argc" "const wchar_t *argv[]"
99.Ft int
100.Fn el_set "EditLine *e" "int op" "..."
101.Ft int
102.Fn el_wset "EditLine *e" "int op" "..."
103.Ft int
104.Fn el_get "EditLine *e" "int op" "..."
105.Ft int
106.Fn el_wget "EditLine *e" "int op" "..."
107.Ft int
108.Fn el_source "EditLine *e" "const char *file"
109.Ft void
110.Fn el_resize "EditLine *e"
111.Ft const LineInfo *
112.Fn el_line "EditLine *e"
113.Ft const LineInfoW *
114.Fn el_wline "EditLine *e"
115.Ft int
116.Fn el_insertstr "EditLine *e" "const char *str"
117.Ft int
118.Fn el_winsertstr "EditLine *e" "const wchar_t *str"
119.Ft void
120.Fn el_deletestr "EditLine *e" "int count"
121.Ft void
122.Fn el_wdeletestr "EditLine *e" "int count"
123.Ft History *
124.Fn history_init void
125.Ft HistoryW *
126.Fn history_winit void
127.Ft void
128.Fn history_end "History *h"
129.Ft void
130.Fn history_wend "HistoryW *h"
131.Ft int
132.Fn history "History *h" "HistEvent *ev" "int op" "..."
133.Ft int
134.Fn history_w "HistoryW *h" "HistEventW *ev" "int op" "..."
135.Ft Tokenizer *
136.Fn tok_init "const char *IFS"
137.Ft TokenizerW *
138.Fn tok_winit "const wchar_t *IFS"
139.Ft void
140.Fn tok_end "Tokenizer *t"
141.Ft void
142.Fn tok_wend "TokenizerW *t"
143.Ft void
144.Fn tok_reset "Tokenizer *t"
145.Ft void
146.Fn tok_wreset "TokenizerW *t"
147.Ft int
148.Fn tok_line "Tokenizer *t" "const LineInfo *li" "int *argc" "const char **argv[]" "int *cursorc" "int *cursoro"
149.Ft int
150.Fn tok_wline "TokenizerW *t" "const LineInfoW *li" "int *argc" "const wchar_t **argv[]" "int *cursorc" "int *cursoro"
151.Ft int
152.Fn tok_str "Tokenizer *t" "const char *str" "int *argc" "const char **argv[]"
153.Ft int
154.Fn tok_wstr "TokenizerW *t" "const wchar_t *str" "int *argc" "const wchar_t **argv[]"
155.Sh DESCRIPTION
156The
157.Nm
158library provides generic line editing, history and tokenization functions,
159similar to those found in
160.Xr sh 1 .
161.Pp
162These functions are available in the
163.Nm libedit
164library (which needs the
165.Nm libcurses
166library).
167Programs should be linked with
168.Fl ledit lcurses .
169.Pp
170The
171.Nm
172library respects the
173.Ev LC_CTYPE
174locale set by the application program and never uses
175.Xr setlocale 3
176to change the locale.
177The only locales supported are UTF-8 and the default C or POSIX locale.
178If any other locale is set, behaviour is undefined.
179.Sh LINE EDITING FUNCTIONS
180The line editing functions use a common data structure,
181.Fa EditLine ,
182which is created by
183.Fn el_init
184and freed by
185.Fn el_end .
186.Pp
187The wide-character functions behave the same way as their narrow
188counterparts.
189.Pp
190The following functions are available:
191.Bl -tag -width 4n
192.It Fn el_init
193Initialize the line editor, and return a data structure
194to be used by all other line editing functions, or
195.Dv NULL
196on failure.
197.Fa prog
198is the name of the invoking program, used when reading the
199.Xr editrc 5
200file to determine which settings to use.
201.Fa fin ,
202.Fa fout
203and
204.Fa ferr
205are the input, output, and error streams (respectively) to use.
206In this documentation, references to
207.Dq the tty
208are actually to this input/output stream combination.
209.It Fn el_end
210Clean up and finish with
211.Fa e ,
212assumed to have been created with
213.Fn el_init .
214.It Fn el_reset
215Reset the tty and the parser.
216This should be called after an error which may have upset the tty's
217state.
218.It Fn el_gets
219Read a line from the tty.
220.Fa count
221is modified to contain the number of characters read.
222Returns the line read if successful, or
223.Dv NULL
224if no characters were read or if an error occurred.
225If an error occurred,
226.Fa count
227is set to \-1 and
228.Dv errno
229contains the error code that caused it.
230The return value may not remain valid across calls to
231.Fn el_gets
232and must be copied if the data is to be retained.
233.It Fn el_wgetc
234Read a wide character from the tty, respecting the current locale,
235or from the input queue described in
236.Xr editline 7
237if that is not empty, and store it in
238.Fa wc .
239If an invalid or incomplete character is found, it is discarded,
240.Va errno
241is set to
242.Er EILSEQ ,
243and the next character is read and stored in
244.Fa wc .
245Returns 1 if a valid character was read, 0 on end of file, or \-1 on
246.Xr read 2
247failure.
248In the latter case,
249.Va errno
250is set to indicate the error.
251.It Fn el_getc
252Read a wide character as described for
253.Fn el_wgetc
254and return 0 on end of file or \-1 on failure.
255If the wide character can be represented as a single-byte character,
256convert it with
257.Xr wctob 3 ,
258store the result in
259.Fa ch ,
260and return 1; otherwise, set
261.Va errno
262to
263.Er ERANGE
264and return \-1.
265In the C or POSIX locale, this simply reads a byte, but for any other
266locale, including UTF-8, this is rarely useful.
267.It Fn el_wpush
268Push the wide character string
269.Fa wcs
270back onto the input queue described in
271.Xr editline 7 .
272If the queue overflows, for example due to a recursive macro,
273or if an error occurs, for example because
274.Fa wcs
275is
276.Dv NULL
277or memory allocation fails, the function beeps at the user,
278but does not report the problem to the caller.
279.It Fn el_push
280Use the current locale to convert the multibyte string
281.Fa mbs
282to a wide character string, and pass the result to
283.Fn el_wpush .
284.It Fn el_parse
285Parses the
286.Fa argv
287array (which is
288.Fa argc
289elements in size)
290to execute builtin
291.Nm
292commands.
293If the command is prefixed with
294.Dq prog :
295then
296.Fn el_parse
297will only execute the command if
298.Dq prog
299matches the
300.Fa prog
301argument supplied to
302.Fn el_init .
303The return value is
304\-1 if the command is unknown,
3050 if there was no error or
306.Dq prog
307didn't match, or
3081 if the command returned an error.
309Refer to
310.Xr editrc 5
311for more information.
312.It Fn el_set
313Set
314.Nm
315parameters.
316.Fa op
317determines which parameter to set, and each operation has its
318own parameter list.
319Returns 0 on success, \-1 on failure.
320.Pp
321The following values for
322.Fa op
323are supported, along with the required argument list:
324.Bl -tag -width 4n
325.It Dv EL_PROMPT , Fa "char *(*f)(EditLine *)"
326Define prompt printing function as
327.Fa f ,
328which is to return a string that contains the prompt.
329.It Dv EL_PROMPT_ESC , Fa "char *(*f)(EditLine *)" , Fa "char c"
330Same as
331.Dv EL_PROMPT ,
332but the
333.Fa c
334argument indicates the start/stop literal prompt character.
335.Pp
336If a start/stop literal character is found in the prompt, the
337character itself
338is not printed, but characters after it are printed directly to the
339terminal without affecting the state of the current line.
340A subsequent second start/stop literal character ends this behavior.
341This is typically used to embed literal escape sequences that change the
342color/style of the terminal in the prompt.
343.Dv 0
344unsets it.
345.It Dv EL_REFRESH
346Re-display the current line on the next terminal line.
347.It Dv EL_RPROMPT , Fa "char *(*f)(EditLine *)"
348Define right side prompt printing function as
349.Fa f ,
350which is to return a string that contains the prompt.
351.It Dv EL_RPROMPT_ESC , Fa "char *(*f)(EditLine *)" , Fa "char c"
352Define the right prompt printing function but with a literal escape character.
353.It Dv EL_TERMINAL , Fa "const char *type"
354Define terminal type of the tty to be
355.Fa type ,
356or to
357.Ev TERM
358if
359.Fa type
360is
361.Dv NULL .
362.It Dv EL_EDITOR , Fa "const char *mode"
363Set editing mode to
364.Fa mode ,
365which must be one of
366.Dq emacs
367or
368.Dq vi .
369.It Dv EL_SIGNAL , Fa "int flag"
370If
371.Fa flag
372is non-zero,
373.Nm
374will install its own signal handler for the following signals when
375reading command input:
376.Dv SIGCONT ,
377.Dv SIGHUP ,
378.Dv SIGINT ,
379.Dv SIGQUIT ,
380.Dv SIGSTOP ,
381.Dv SIGTERM ,
382.Dv SIGTSTP ,
383and
384.Dv SIGWINCH .
385Otherwise, the current signal handlers will be used.
386.It Dv EL_BIND , Fa "const char *" , Fa "..." , Dv NULL
387Perform the
388.Ic bind
389builtin command.
390Refer to
391.Xr editrc 5
392for more information.
393.It Dv EL_ECHOTC , Fa "const char *" , Fa "..." , Dv NULL
394Perform the
395.Ic echotc
396builtin command.
397Refer to
398.Xr editrc 5
399for more information.
400.It Dv EL_SETTC , Fa "const char *" , Fa "..." , Dv NULL
401Perform the
402.Ic settc
403builtin command.
404Refer to
405.Xr editrc 5
406for more information.
407.It Dv EL_SETTY , Fa "const char *" , Fa "..." , Dv NULL
408Perform the
409.Ic setty
410builtin command.
411Refer to
412.Xr editrc 5
413for more information.
414.It Dv EL_TELLTC , Fa "const char *" , Fa "..." , Dv NULL
415Perform the
416.Ic telltc
417builtin command.
418Refer to
419.Xr editrc 5
420for more information.
421.It Dv EL_ADDFN , Fa "const char *name" , Fa "const char *help" , \
422Fa "unsigned char (*func)(EditLine *e, int ch)"
423Add a user defined function,
424.Fn func ,
425referred to as
426.Fa name
427which is invoked when a key which is bound to
428.Fa name
429is entered.
430.Fa help
431is a description of
432.Fa name .
433At invocation time,
434.Fa ch
435is the key which caused the invocation.
436The return value of
437.Fn func
438should be one of:
439.Bl -tag -width "CC_REDISPLAY"
440.It Dv CC_NORM
441Add a normal character.
442.It Dv CC_NEWLINE
443End of line was entered.
444.It Dv CC_EOF
445EOF was entered.
446.It Dv CC_ARGHACK
447Expecting further command input as arguments, do nothing visually.
448.It Dv CC_REFRESH
449Refresh display.
450.It Dv CC_REFRESH_BEEP
451Refresh display, and beep.
452.It Dv CC_CURSOR
453Cursor moved, so update and perform
454.Dv CC_REFRESH .
455.It Dv CC_REDISPLAY
456Redisplay entire input line.
457This is useful if a key binding outputs extra information.
458.It Dv CC_ERROR
459An error occurred.
460Beep, and flush tty.
461.It Dv CC_FATAL
462Fatal error, reset tty to known state.
463.El
464.It Dv EL_HIST , Fa "History *(*func)(History *, int op, ...)" , \
465Fa "const char *ptr"
466Defines which history function to use, which is usually
467.Fn history .
468.Fa ptr
469should be the value returned by
470.Fn history_init .
471.It Dv EL_EDITMODE , Fa "int flag"
472If
473.Fa flag
474is non-zero,
475editing is enabled (the default).
476Note that this is only an indication, and does not
477affect the operation of
478.Nm .
479At this time, it is the caller's responsibility to
480check this
481(using
482.Fn el_get )
483to determine if editing should be enabled or not.
484.It Dv EL_UNBUFFERED , Fa "int flag"
485If
486.Fa flag
487is zero,
488unbuffered mode is disabled (the default).
489In unbuffered mode,
490.Fn el_gets
491will return immediately after processing a single character.
492.It Dv EL_GETCFN , Fa "el_rfunc_t f"
493Whenever reading a character, use the function
494.Bd -ragged -offset indent -compact
495.Ft int
496.Fo f
497.Fa "EditLine *e"
498.Fa "wchar_t *wc"
499.Fc
500.Ed
501which stores the character in
502.Fa wc
503and returns 1 on success, 0 on end of file, or \-1 on I/O or encoding
504errors.
505Functions internally using it include
506.Fn el_wgets ,
507.Fn el_wgetc ,
508.Fn el_gets ,
509and
510.Fn el_getc .
511Initially, a builtin function is installed, and replacing it
512is discouraged because writing such a function is very error prone.
513The builtin function can be restored at any time by passing the
514special value
515.Dv EL_BUILTIN_GETCFN
516instead of a function pointer.
517.It Dv EL_CLIENTDATA , Fa "void *data"
518Register
519.Fa data
520to be associated with this EditLine structure.
521It can be retrieved with the corresponding
522.Fn el_get
523call.
524.It Dv EL_SETFP , Fa "int fd" , Fa "FILE *fp"
525Set the current
526.Nm editline
527file pointer for
528.Dq input
529.Fa fd
530=
531.Dv 0 ,
532.Dq output
533.Fa fd
534=
535.Dv 1 ,
536or
537.Dq error
538.Fa fd
539=
540.Dv 2
541from
542.Fa fp .
543.El
544.It Fn el_get
545Get
546.Nm
547parameters.
548.Fa op
549determines which parameter to retrieve into
550.Fa result .
551Returns 0 if successful, \-1 otherwise.
552.Pp
553The following values for
554.Fa op
555are supported, along with actual type of
556.Fa result :
557.Bl -tag -width 4n
558.It Dv EL_PROMPT , Fa "char *(*f)(EditLine *)" , Fa "char *c"
559Set
560.Fa f
561to a pointer to the function that displays the prompt.
562If
563.Fa c
564is not
565.Dv NULL ,
566set it to the start/stop literal prompt character.
567.It Dv EL_RPROMPT , Fa "char *(*f)(EditLine *)" , Fa "char *c"
568Set
569.Fa f
570to a pointer to the function that displays the prompt.
571If
572.Fa c
573is not
574.Dv NULL ,
575set it to the start/stop literal prompt character.
576.It Dv EL_EDITOR , Fa "const char **n"
577Set the name of the editor in
578.Fa n ,
579which will be one of
580.Dq emacs
581or
582.Dq vi .
583.It Dv EL_GETTC , Fa "const char *name" , Fa "void *value"
584If
585.Fa name
586is a valid
587.Xr termcap 5
588capability set
589.Fa value
590to the current value of that capability.
591.It Dv EL_SIGNAL , Fa "int *s"
592Set
593.Fa s
594to non-zero if
595.Nm
596has installed private signal handlers (see
597.Fn el_get
598above).
599.It Dv EL_EDITMODE , Fa "int *c"
600Set
601.Fa c
602to non-zero if editing is enabled.
603.It Dv EL_GETCFN , Fa "el_rfunc_t *f"
604Set
605.Fa f
606to a pointer to the function that reads characters, or to
607.Dv EL_BUILTIN_GETCFN
608if the builtin function is in use.
609.It Dv EL_CLIENTDATA , Fa "void **data"
610Set
611.Fa data
612to the previously registered client data set by an
613.Fn el_set
614call.
615.It Dv EL_UNBUFFERED , Fa "int *c"
616Set
617.Fa c
618to non-zero if unbuffered mode is enabled.
619.It Dv EL_PREP_TERM , Fa "int"
620Sets or clears terminal editing mode.
621.It Dv EL_GETFP , Fa "int fd", Fa "FILE **fp"
622Set
623.Fa fp
624to the current
625.Nm editline
626file pointer for
627.Dq input
628.Fa fd
629=
630.Dv 0 ,
631.Dq output
632.Fa fd
633=
634.Dv 1 ,
635or
636.Dq error
637.Fa fd
638=
639.Dv 2 .
640.El
641.It Fn el_source
642Initialize
643.Nm
644by reading the contents of
645.Fa file .
646.Fn el_parse
647is called for each line in
648.Fa file .
649If
650.Fa file
651is
652.Dv NULL ,
653try
654.Pa $HOME/.editrc .
655Refer to
656.Xr editrc 5
657for details on the format of
658.Fa file .
659.Fn el_source
660returns 0 on success and \-1 on error.
661.It Fn el_resize
662Must be called if the terminal size changes.
663If
664.Dv EL_SIGNAL
665has been set with
666.Fn el_set ,
667then this is done automatically.
668Otherwise, it's the responsibility of the application to call
669.Fn el_resize
670on the appropriate occasions.
671.It Fn el_line
672Return the editing information for the current line in a
673.Fa LineInfo
674structure, which is defined as follows:
675.Bd -literal
676typedef struct lineinfo {
677    const char *buffer;    /* address of buffer */
678    const char *cursor;    /* address of cursor */
679    const char *lastchar;  /* address of last character */
680} LineInfo;
681.Ed
682.Pp
683.Fa buffer
684is not NUL terminated.
685This function may be called after
686.Fn el_gets
687to obtain the
688.Fa LineInfo
689structure pertaining to line returned by that function,
690and from within user defined functions added with
691.Dv EL_ADDFN .
692.It Fn el_insertstr
693Insert
694.Fa str
695into the line at the cursor.
696Returns \-1 if
697.Fa str
698is empty or won't fit, and 0 otherwise.
699.It Fn el_deletestr
700Delete
701.Fa count
702characters before the cursor.
703.El
704.Sh HISTORY LIST FUNCTIONS
705The history functions use a common data structure,
706.Fa History ,
707which is created by
708.Fn history_init
709and freed by
710.Fn history_end .
711.Pp
712The following functions are available:
713.Bl -tag -width 4n
714.It Fn history_init
715Initialize the history list, and return a data structure
716to be used by all other history list functions, or
717.Dv NULL
718on failure.
719.It Fn history_end
720Clean up and finish with
721.Fa h ,
722assumed to have been created with
723.Fn history_init .
724.It Fn history
725Perform operation
726.Fa op
727on the history list, with optional arguments as needed by the
728operation.
729.Fa ev
730is changed accordingly to operation.
731The following values for
732.Fa op
733are supported, along with the required argument list:
734.Bl -tag -width 4n
735.It Dv H_SETSIZE , Fa "int size"
736Set size of history to
737.Fa size
738elements.
739.It Dv H_GETSIZE
740Get number of events currently in history.
741.It Dv H_END
742Cleans up and finishes with
743.Fa h ,
744assumed to be created with
745.Fn history_init .
746.It Dv H_CLEAR
747Clear the history.
748.It Dv H_FUNC , Fa "void *ptr" , Fa "history_gfun_t first" , \
749Fa "history_gfun_t next" , Fa "history_gfun_t last" , \
750Fa "history_gfun_t prev" , Fa "history_gfun_t curr" , \
751Fa "history_sfun_t set" , Fa "history_vfun_t clear" , \
752Fa "history_efun_t enter" , Fa "history_efun_t add"
753Define functions to perform various history operations.
754.Fa ptr
755is the argument given to a function when it's invoked.
756.It Dv H_FIRST
757Return the first element in the history.
758.It Dv H_LAST
759Return the last element in the history.
760.It Dv H_PREV
761Return the previous element in the history.
762It is newer than the current one.
763.It Dv H_NEXT
764Return the next element in the history.
765It is older than the current one.
766.It Dv H_CURR
767Return the current element in the history.
768.It Dv H_SET
769Set the cursor to point to the requested element.
770.It Dv H_ADD , Fa "const char *str"
771Append
772.Fa str
773to the current element of the history, or perform the
774.Dv H_ENTER
775operation with argument
776.Fa str
777if there is no current element.
778.It Dv H_APPEND , Fa "const char *str"
779Append
780.Fa str
781to the last new element of the history.
782.It Dv H_ENTER , Fa "const char *str"
783Add
784.Fa str
785as a new element to the history and, if necessary,
786removing the oldest entry to keep the list to the created size.
787If
788.Dv H_SETUNIQUE
789has been called with a non-zero argument, the element
790will not be entered into the history if its contents match
791the ones of the current history element.
792If the element is entered
793.Fn history
794returns 1; if it is ignored as a duplicate returns 0.
795Finally
796.Fn history
797returns \-1 if an error occurred.
798.It Dv H_PREV_STR , Fa "const char *str"
799Return the closest previous event that starts with
800.Fa str .
801.It Dv H_NEXT_STR , Fa "const char *str"
802Return the closest next event that starts with
803.Fa str .
804.It Dv H_PREV_EVENT , Fa "int e"
805Return the previous event numbered
806.Fa e .
807.It Dv H_NEXT_EVENT , Fa "int e"
808Return the next event numbered
809.Fa e .
810.It Dv H_LOAD , Fa "const char *file"
811Load the history list stored in
812.Fa file .
813.It Dv H_SAVE , Fa "const char *file"
814Save the history list to
815.Fa file .
816.It Dv H_SAVE_FP , Fa "FILE *fp"
817Save the history list to the opened
818.Ft FILE
819pointer
820.Fa fp .
821.It Dv H_SETUNIQUE , Fa "int unique"
822Set flag that adjacent identical event strings should not be entered
823into the history.
824.It Dv H_GETUNIQUE
825Retrieve the current setting if adjacent identical elements should
826be entered into the history.
827.It Dv H_DEL , Fa "int e"
828Delete the event numbered
829.Fa e .
830This function is only provided for
831.Xr readline 3
832compatibility.
833The caller is responsible for free'ing the string in the returned
834.Fa HistEvent .
835.El
836.Pp
837.Fn history
838returns \*[Gt]= 0 if the operation
839.Fa op
840succeeds.
841Otherwise, \-1 is returned and
842.Fa ev
843is updated to contain more details about the error.
844.El
845.Sh TOKENIZATION FUNCTIONS
846The tokenization functions use a common data structure,
847.Fa Tokenizer ,
848which is created by
849.Fn tok_init
850and freed by
851.Fn tok_end .
852.Pp
853The following functions are available:
854.Bl -tag -width 4n
855.It Fn tok_init
856Initialize the tokenizer, and return a data structure
857to be used by all other tokenizer functions.
858.Fa IFS
859contains the Input Field Separators, which defaults to
860.Aq space ,
861.Aq tab ,
862and
863.Aq newline
864if
865.Dv NULL .
866.It Fn tok_end
867Clean up and finish with
868.Fa t ,
869assumed to have been created with
870.Fn tok_init .
871.It Fn tok_reset
872Reset the tokenizer state.
873Use after a line has been successfully tokenized
874by
875.Fn tok_line
876or
877.Fn tok_str
878and before a new line is to be tokenized.
879.It Fn tok_line
880Tokenize
881.Fa li ,
882If successful, modify:
883.Fa argv
884to contain the words,
885.Fa argc
886to contain the number of words,
887.Fa cursorc
888(if not
889.Dv NULL )
890to contain the index of the word containing the cursor,
891and
892.Fa cursoro
893(if not
894.Dv NULL )
895to contain the offset within
896.Fa argv[cursorc]
897of the cursor.
898.Pp
899Returns
9000 if successful,
901\-1 for an internal error,
9021 for an unmatched single quote,
9032 for an unmatched double quote,
904and
9053 for a backslash quoted
906.Aq newline .
907A positive exit code indicates that another line should be read
908and tokenization attempted again.
909.
910.It Fn tok_str
911A simpler form of
912.Fn tok_line ;
913.Fa str
914is a NUL terminated string to tokenize.
915.El
916.
917.\"XXX.Sh EXAMPLES
918.\"XXX: provide some examples
919.Sh SEE ALSO
920.Xr sh 1 ,
921.Xr curses 3 ,
922.Xr signal 3 ,
923.Xr editrc 5 ,
924.Xr termcap 5 ,
925.Xr editline 7
926.Sh HISTORY
927The
928.Nm
929library first appeared in
930.Bx 4.4 .
931.Dv CC_REDISPLAY
932appeared in
933.Nx 1.3 .
934.Dv CC_REFRESH_BEEP ,
935.Dv EL_EDITMODE
936and the readline emulation appeared in
937.Nx 1.4 .
938.Dv EL_RPROMPT
939appeared in
940.Nx 1.5 .
941.Sh AUTHORS
942.An -nosplit
943The
944.Nm
945library was written by
946.An Christos Zoulas .
947.An Luke Mewburn
948wrote this manual and implemented
949.Dv CC_REDISPLAY ,
950.Dv CC_REFRESH_BEEP ,
951.Dv EL_EDITMODE ,
952and
953.Dv EL_RPROMPT .
954.An Jaromir Dolecek
955implemented the readline emulation.
956.An Johny Mattsson
957implemented wide-character support.
958.Sh BUGS
959At this time, it is the responsibility of the caller to
960check the result of the
961.Dv EL_EDITMODE
962operation of
963.Fn el_get
964(after an
965.Fn el_source
966or
967.Fn el_parse )
968to determine if
969.Nm
970should be used for further input.
971I.e.,
972.Dv EL_EDITMODE
973is purely an indication of the result of the most recent
974.Xr editrc 5
975.Ic edit
976command.
977