EDITLINE(3)EDITLINE(3)NAME
editline, el_init, el_init_fd, el_end, el_reset, el_gets, el_wgets,
el_getc, el_wgetc, el_push, el_wpush, el_parse, el_wparse, el_set,
el_wset, el_get, el_wget, el_source, el_resize, el_cursor, el_line,
el_wline, el_insertstr, el_winsertstr, el_deletestr, el_wdeletestr,
history_init, history_winit, history_end, history_wend, history, his‐
tory_w, tok_init, tok_winit, tok_end, tok_wend, tok_reset, tok_wreset,
tok_line, tok_wline, tok_str tok_wstr - line editor, history and tok‐
enization functions
LIBRARY
Command Line Editor Library (libedit, -ledit)
SYNOPSIS
#include <histedit.h>
EditLine *
el_init(const char *prog, FILE *fin, FILE *fout, FILE *ferr);
EditLine *
el_init_fd(const char *prog, FILE *fin, FILE *fout, FILE *ferr, int
fdin, int fdout, int fderr);
void
el_end(EditLine *e);
void
el_reset(EditLine *e);
const char *
el_gets(EditLine *e, int *count);
const wchar_t *
el_wgets(EditLine *e, int *count);
int
el_getc(EditLine *e, char *ch);
int
el_wgetc(EditLine *e, wchar_t *ch);
void
el_push(EditLine *e, const char *str);
void
el_wpush(EditLine *e, const wchar_t *str);
int
el_parse(EditLine *e, int argc, const char *argv[]);
int
el_wparse(EditLine *e, int argc, const wchar_t *argv[]);
int
el_set(EditLine *e, int op, ...);
int
el_wset(EditLine *e, int op, ...);
int
el_get(EditLine *e, int op, ...);
int
el_wget(EditLine *e, int op, ...);
int
el_source(EditLine *e, const char *file);
void
el_resize(EditLine *e); int() el_cursor(EditLine *e, int count)
const LineInfo *
el_line(EditLine *e);
const LineInfoW *
el_wline(EditLine *e);
int
el_insertstr(EditLine *e, const char *str);
int
el_winsertstr(EditLine *e, const wchar_t *str);
void
el_deletestr(EditLine *e, int count);
void
el_wdeletestr(EditLine *e, int count);
History *
history_init();
HistoryW *
history_winit();
void
history_end(History *h);
void
history_wend(HistoryW *h);
int
history(History *h, HistEvent *ev, int op, ...);
int
history_w(HistoryW *h, HistEventW *ev, int op, ...);
Tokenizer *
tok_init(const char *IFS);
TokenizerW *
tok_winit(const wchar_t *IFS);
void
tok_end(Tokenizer *t);
void
tok_wend(TokenizerW *t);
void
tok_reset(Tokenizer *t);
void
tok_wreset(TokenizerW *t);
int
tok_line(Tokenizer *t, const LineInfo *li, int *argc, const char
**argv[], int *cursorc, int *cursoro);
int
tok_wline(TokenizerW *t, const LineInfoW *li, int *argc, const wchar_t
**argv[], int *cursorc, int *cursoro);
int
tok_str(Tokenizer *t, const char *str, int *argc, const char **argv[]);
int
tok_wstr(TokenizerW *t, const wchar_t *str, int *argc, const wchar_t
**argv[]);
DESCRIPTION
The editline library provides generic line editing, history and tok‐
enization functions, similar to those found in sh(1).
These functions are available in the libedit library (which needs the
libtermcap library). Programs should be linked with -ledit ltermcap .
LINE EDITING FUNCTIONS
The line editing functions use a common data structure, EditLine, which
is created by el_init() or el_init_fd() and freed by el_end().
The wide-character functions behave the same way as their narrow coun‐
terparts.
The following functions are available:
el_init()
Initialise the line editor, and return a data structure to be
used by all other line editing functions. prog is the name of
the invoking program, used when reading the editrc(5) file to
determine which settings to use. fin, fout and ferr are the
input, output, and error streams (respectively) to use. In this
documentation, references to ``the tty'' are actually to this
input/output stream combination.
el_init_fd()
Like el_init() but allows specifying file descriptors for the
stdio(3) corresponding streams, in case those were created with
funopen(3).
el_end()
Clean up and finish with e, assumed to have been created with
el_init() or el_init_fd().
el_reset()
Reset the tty and the parser. This should be called after an
error which may have upset the tty's state.
el_gets()
Read a line from the tty. count is modified to contain the num‐
ber of characters read. Returns the line read if successful, or
NULL if no characters were read or if an error occurred. If an
error occurred, count is set to -1 and errno contains the error
code that caused it. The return value may not remain valid
across calls to el_gets() and must be copied if the data is to
be retained.
el_getc()
Read a character from the tty. ch is modified to contain the
character read. Returns the number of characters read if suc‐
cessful, -1 otherwise, in which case errno can be inspected for
the cause.
el_push()
Pushes str back onto the input stream. This is used by the
macro expansion mechanism. Refer to the description of bind -s
in editrc(5) for more information.
el_parse()
Parses the argv array (which is argc elements in size) to exe‐
cute builtin editline commands. If the command is prefixed with
``prog :'' then el_parse() will only execute the command if
``prog'' matches the prog argument supplied to el_init(). The
return value is -1 if the command is unknown, 0 if there was no
error or ``prog'' didn't match, or 1 if the command returned an
error. Refer to editrc(5) for more information.
el_set()
Set editline parameters. op determines which parameter to set,
and each operation has its own parameter list.
The following values for op are supported, along with the
required argument list:
EL_PROMPT , char *(*f)(EditLine *)
Define prompt printing function as f, which is to return
a string that contains the prompt.
EL_PROMPT_ESC , char *(*f)(EditLine *), Fa char c
Same as EL_PROMPT , but the c argument indicates the
start/stop literal prompt character.
If a start/stop literal character is found in the prompt,
the character itself is not printed, but characters after
it are printed directly to the terminal without affecting
the state of the current line. A subsequent second
start/stop literal character ends this behavior. This is
typically used to embed literal escape sequences that
change the color/style of the terminal in the prompt. 0
unsets it.
EL_REFRESH
Re-display the current line on the next terminal line.
EL_RPROMPT , char *(*f)(EditLine *)
Define right side prompt printing function as f, which is
to return a string that contains the prompt.
EL_RPROMPT_ESC , char *(*f)(EditLine *), Fa char c
Define the right prompt printing function but with a lit‐
eral escape character.
EL_TERMINAL , const char *type
Define terminal type of the tty to be type, or to TERM if
type is NULL .
EL_EDITOR , const char *mode
Set editing mode to mode, which must be one of ``emacs''
or ``vi''.
EL_SIGNAL , int flag
If flag is non-zero, editline will install its own signal
handler for the following signals when reading command
input: SIGCONT , SIGHUP , SIGINT , SIGQUIT , SIGSTOP ,
SIGTERM , SIGTSTP , and SIGWINCH . Otherwise, the cur‐
rent signal handlers will be used.
EL_BIND , const char *, Fa ..., Dv NULL
Perform the bind builtin command. Refer to editrc(5) for
more information.
EL_ECHOTC , const char *, Fa ..., Dv NULL
Perform the echotc builtin command. Refer to editrc(5)
for more information.
EL_SETTC , const char *, Fa ..., Dv NULL
Perform the settc builtin command. Refer to editrc(5)
for more information.
EL_SETTY , const char *, Fa ..., Dv NULL
Perform the setty builtin command. Refer to editrc(5)
for more information.
EL_TELLTC , const char *, Fa ..., Dv NULL
Perform the telltc builtin command. Refer to editrc(5)
for more information.
EL_ADDFN , const char *name, Fa const char *help,
Fa "unsigned char (*func)(EditLine *e, int ch)" Add a
user defined function, func(), referred to as name which
is invoked when a key which is bound to name is entered.
help is a description of name. At invocation time, ch is
the key which caused the invocation. The return value of
func() should be one of:
CC_NORM
Add a normal character.
CC_NEWLINE
End of line was entered.
CC_EOF EOF was entered.
CC_ARGHACK
Expecting further command input as arguments, do
nothing visually.
CC_REFRESH
Refresh display.
CC_REFRESH_BEEP
Refresh display, and beep.
CC_CURSOR
Cursor moved, so update and perform CC_REFRESH .
CC_REDISPLAY
Redisplay entire input line. This is useful if a
key binding outputs extra information.
CC_ERROR
An error occurred. Beep, and flush tty.
CC_FATAL
Fatal error, reset tty to known state.
EL_HIST , History *(*func)(History *, int op, ...),
Fa "const char *ptr" Defines which history function to
use, which is usually history(). ptr should be the value
returned by history_init().
EL_EDITMODE , int flag
If flag is non-zero, editing is enabled (the default).
Note that this is only an indication, and does not affect
the operation of . At this time, it is the caller's
responsibility to check this (using el_get() ) to deter‐
mine if editing should be enabled or not.
EL_UNBUFFERED , int flag
If flag is zero, unbuffered mode is disabled (the
default). In unbuffered mode, el_gets() will return
immediately after processing a single character.
EL_GETCFN , int (*f)(EditLine *, char *c)
Define the character reading function as f, which is to
return the number of characters read and store them in c.
This function is called internally by el_gets() and
el_getc(). The builtin function can be set or restored
with the special function name ``Dv EL_BUILTIN_GETCFN''.
EL_CLIENTDATA , void *data
Register data to be associated with this EditLine struc‐
ture. It can be retrieved with the corresponding
el_get() call.
EL_SETFP , int fd, Fa FILE *fp
Set the current editline file pointer for ``input'' fd =
0 , ``output'' fd = 1 , or ``error'' fd = 2 from fp.
el_get()
Get editline parameters. op determines which parameter to
retrieve into result. Returns 0 if successful, -1 otherwise.
The following values for op are supported, along with actual
type of result :
EL_PROMPT , char *(*f)(EditLine *), Fa char *c
Return a pointer to the function that displays the prompt
in f. If c is not NULL , return the start/stop literal
prompt character in it.
EL_RPROMPT , char *(*f)(EditLine *), Fa char *c
Return a pointer to the function that displays the prompt
in f. If c is not NULL , return the start/stop literal
prompt character in it.
EL_EDITOR , const char **
Return the name of the editor, which will be one of
``emacs'' or ``vi''.
EL_GETTC , const char *name, Fa void *value
Return non-zero if name is a valid termcap(5) capability
and set value to the current value of that capability.
EL_SIGNAL , int *
Return non-zero if editline has installed private signal
handlers (see el_get() above).
EL_EDITMODE , int *
Return non-zero if editing is enabled.
EL_GETCFN , int (**f)(EditLine *, char *)
Return a pointer to the function that read characters,
which is equal to ``Dv EL_BUILTIN_GETCFN'' in the case of
the default builtin function.
EL_CLIENTDATA , void **data
Retrieve data previously registered with the correspond‐
ing el_set() call.
EL_UNBUFFERED , int
Return non-zero if unbuffered mode is enabled.
EL_PREP_TERM , int
Sets or clears terminal editing mode.
EL_GETFP , int fd", Fa FILE **fp
Return in fp the current editline file pointer for
``input'' fd = 0 , ``output'' fd = 1 , or ``error'' fd =
2 .
el_source()
Initialise editline by reading the contents of file. el_parse()
is called for each line in file. If file is NULL , try
$HOME/.editrc. Refer to editrc(5) for details on the format of
file.
el_resize()
Must be called if the terminal size changes. If EL_SIGNAL has
been set with el_set(), then this is done automatically. Other‐
wise, it's the responsibility of the application to call
el_resize() on the appropriate occasions.
el_cursor()
Move the cursor to the right (if positive) or to the left (if
negative) count characters. Returns the resulting offset of the
cursor from the beginning of the line.
el_line()
Return the editing information for the current line in a Line‐
Info structure, which is defined as follows:
typedef struct lineinfo {
const char *buffer; /* address of buffer */
const char *cursor; /* address of cursor */
const char *lastchar; /* address of last character */
} LineInfo;
buffer is not NUL terminated. This function may be called after
el_gets() to obtain the LineInfo structure pertaining to line
returned by that function, and from within user defined func‐
tions added with EL_ADDFN .
el_insertstr()
Insert str into the line at the cursor. Returns -1 if str is
empty or won't fit, and 0 otherwise.
el_deletestr()
Delete count characters before the cursor.
HISTORY LIST FUNCTIONS
The history functions use a common data structure, History, which is
created by history_init() and freed by history_end().
The following functions are available:
history_init()
Initialise the history list, and return a data structure to be
used by all other history list functions.
history_end()
Clean up and finish with h, assumed to have been created with
history_init().
history()
Perform operation op on the history list, with optional argu‐
ments as needed by the operation. ev is changed accordingly to
operation. The following values for op are supported, along
with the required argument list:
H_SETSIZE , int size
Set size of history to size elements.
H_GETSIZE
Get number of events currently in history.
H_END Cleans up and finishes with h, assumed to be created with
history_init().
H_CLEAR
Clear the history.
H_FUNC , void *ptr, Fa history_gfun_t first,
Fa "history_gfun_t next" , Fa "history_gfun_t last" , Fa
"history_gfun_t prev" , Fa "history_gfun_t curr" , Fa
"history_sfun_t set" , Fa "history_vfun_t clear" , Fa
"history_efun_t enter" , Fa "history_efun_t add" Define
functions to perform various history operations. ptr is
the argument given to a function when it's invoked.
H_FIRST
Return the first element in the history.
H_LAST Return the last element in the history.
H_PREV Return the previous element in the history.
H_NEXT Return the next element in the history.
H_CURR Return the current element in the history.
H_SET Set the cursor to point to the requested element.
H_ADD , const char *str
Append str to the current element of the history, or per‐
form the H_ENTER operation with argument str if there is
no current element.
H_APPEND , const char *str
Append str to the last new element of the history.
H_ENTER , const char *str
Add str as a new element to the history, and, if neces‐
sary, removing the oldest entry to keep the list to the
created size. If H_SETUNIQUE was has been called with a
non-zero arguments, the element will not be entered into
the history if its contents match the ones of the current
history element. If the element is entered history()
returns 1, if it is ignored as a duplicate returns 0.
Finally history() returns -1 if an error occurred.
H_PREV_STR , const char *str
Return the closest previous event that starts with str.
H_NEXT_STR , const char *str
Return the closest next event that starts with str.
H_PREV_EVENT , int e
Return the previous event numbered e.
H_NEXT_EVENT , int e
Return the next event numbered e.
H_LOAD , const char *file
Load the history list stored in file.
H_SAVE , const char *file
Save the history list to file.
H_SETUNIQUE , int unique
Set flag that adjacent identical event strings should not
be entered into the history.
H_GETUNIQUE
Retrieve the current setting if adjacent identical ele‐
ments should be entered into the history.
H_DEL , int e
Delete the event numbered e. This function is only pro‐
vided for readline(3) compatibility. The caller is
responsible for free'ing the string in the returned His‐
tEvent.
history() returns = 0 if the operation op succeeds. Otherwise, -1 is
returned and ev is updated to contain more details about the error.
TOKENIZATION FUNCTIONS
The tokenization functions use a common data structure, Tokenizer,
which is created by tok_init() and freed by tok_end().
The following functions are available:
tok_init()
Initialise the tokenizer, and return a data structure to be used
by all other tokenizer functions. IFS contains the Input Field
Separators, which defaults to <space ,> <tab ,> and <newline> if
NULL .
tok_end()
Clean up and finish with t, assumed to have been created with
tok_init().
tok_reset()
Reset the tokenizer state. Use after a line has been success‐
fully tokenized by tok_line() or tok_str() and before a new line
is to be tokenized.
tok_line()
Tokenize li, If successful, modify: argv to contain the words,
argc to contain the number of words, cursorc (if not NULL ) to
contain the index of the word containing the cursor, and cursoro
(if not NULL ) to contain the offset within argv[cursorc] of the
cursor.
Returns 0 if successful, -1 for an internal error, 1 for an
unmatched single quote, 2 for an unmatched double quote, and 3
for a backslash quoted <newline .> A positive exit code indi‐
cates that another line should be read and tokenization
attempted again.
tok_str()
A simpler form of tok_line(; ) str is a NUL terminated string to
tokenize.
SEE ALSOsh(1), signal(3), termcap(3), editrc(5), termcap(5)HISTORY
The editline library first appeared in Bx 4.4 . CC_REDISPLAY appeared
in Nx 1.3 . CC_REFRESH_BEEP , EL_EDITMODE and the readline emulation
appeared in Nx 1.4 . EL_RPROMPT appeared in Nx 1.5 .
AUTHORS
The editline library was written by Christos Zoulas. Luke Mewburn
wrote this manual and implemented CC_REDISPLAY , CC_REFRESH_BEEP ,
EL_EDITMODE , and EL_RPROMPT . Jaromir Dolecek implemented the read‐
line emulation. Johny Mattsson implemented wide-character support.
BUGS
At this time, it is the responsibility of the caller to check the
result of the EL_EDITMODE operation of el_get() (after an el_source()
or el_parse() ) to determine if editline should be used for further
input. I.e., EL_EDITMODE is purely an indication of the result of the
most recent editrc(5) edit command.
July 12, 2013 EDITLINE(3)