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,
history_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 tokenization 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 *wc);
void
el_push(
EditLine
*e,
const char *mbs);
void
el_wpush(
EditLine
*e,
const wchar_t
*wcs);
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(
void);
HistoryW *
history_winit(
void);
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 tokenization 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.
The
editline library respects the
LC_CTYPE
locale set by the application program and
never uses
setlocale(3) to
change the locale. The only locales supported are UTF-8 and the default C or
POSIX locale. If any other locale is set, behaviour is undefined.
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 counterparts.
The following functions are available:
-
-
- el_init()
- Initialize the line editor, and return a data structure to
be used by all other line editing functions, or
NULL
on failure. 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 number 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_wgetc()
- Read a wide character from the tty, respecting the current
locale, or from the input queue described in
editline(7) if that is not
empty, and store it in wc. If an invalid or
incomplete character is found, it is discarded,
errno is set to
EILSEQ
, and
the next character is read and stored in wc. Returns
1 if a valid character was read, 0 on end of file, or -1 on
read(2) failure. In the latter
case, errno is set to indicate the error.
-
-
- el_getc()
- Read a wide character as described for
el_wgetc() and return 0 on end of file or -1 on failure.
If the wide character can be represented as a single-byte character,
convert it with wctob(3),
store the result in ch, and return 1; otherwise, set
errno to
ERANGE
and return
-1. In the C or POSIX locale, this simply reads a byte, but for any other
locale, including UTF-8, this is rarely useful.
-
-
- el_wpush()
- Push the wide character string wcs
back onto the input queue described in
editline(7). If the queue
overflows, for example due to a recursive macro, or if an error occurs,
for example because wcs is
NULL
or memory allocation fails, the function
beeps at the user, but does not report the problem to the caller.
-
-
- el_push()
- Use the current locale to convert the multibyte string
mbs to a wide character string, and pass the result
to el_wpush().
-
-
- el_parse()
- Parses the argv array (which is
argc elements in size) to execute 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. Returns 0 on success, -1 on failure.
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 *), 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. Note that the literal
escape character cannot be the last character in the prompt, as the
escape sequence is attached to the next character 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 *), char
c
- Define the right prompt printing function but with a
literal 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 current signal handlers will be used.
-
-
EL_BIND
,
const char *, ...,
NULL
- Perform the bind builtin command.
Refer to editrc(5) for
more information.
-
-
EL_ECHOTC
,
const char *, ...,
NULL
- Perform the echotc builtin command.
Refer to editrc(5) for
more information.
-
-
EL_SETTC
,
const char *, ...,
NULL
- Perform the settc builtin command.
Refer to editrc(5) for
more information.
-
-
EL_SETTY
,
const char *, ...,
NULL
- Perform the setty builtin command.
Refer to editrc(5) for
more information.
-
-
EL_TELLTC
,
const char *, ...,
NULL
- Perform the telltc builtin command.
Refer to editrc(5) for
more information.
-
-
EL_ADDFN
,
const char *name, const char
*help, 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, ...),
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 editline. At this time,
it is the caller's responsibility to check this (using
el_get()) to determine 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
,
el_rfunc_t f
- Whenever reading a character, use the function
int
f(EditLine *e,
wchar_t *wc);
which stores the character in wc and returns 1 on
success, 0 on end of file, or -1 on I/O or encoding errors. Functions
internally using it include el_wgets(),
el_wgetc(), el_gets(), and
el_getc(). Initially, a builtin function is
installed, and replacing it is discouraged because writing such a
function is very error prone. The builtin function can be restored at
any time by passing the special value
EL_BUILTIN_GETCFN
instead of a function
pointer.
-
-
EL_CLIENTDATA
,
void *data
- Register data to be associated
with this EditLine structure. It can be retrieved with the
corresponding el_get() call.
-
-
EL_SETFP
,
int fd, 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 *), char
*c
- Set f to a pointer to the
function that displays the prompt. If c is not
NULL
, set it to the start/stop literal prompt
character.
-
-
EL_RPROMPT
,
char *(*f)(EditLine *), char
*c
- Set f to a pointer to the
function that displays the prompt. If c is not
NULL
, set it to the start/stop literal prompt
character.
-
-
EL_EDITOR
,
const char **n
- Set the name of the editor in n,
which will be one of “emacs” or “vi”.
-
-
EL_GETTC
,
const char *name, void
*value
- If name is a valid
termcap(5) capability
set value to the current value of that
capability.
-
-
EL_SIGNAL
,
int *s
- Set s to non-zero if
editline has installed private signal handlers (see
el_get() above).
-
-
EL_EDITMODE
,
int *c
- Set c to non-zero if editing is
enabled.
-
-
EL_GETCFN
,
el_rfunc_t *f
- Set f to a pointer to the
function that reads characters, or to
EL_BUILTIN_GETCFN
if the builtin function is
in use.
-
-
EL_CLIENTDATA
,
void **data
- Set data to the previously
registered client data set by an el_set() call.
-
-
EL_UNBUFFERED
,
int *c
- Set c to non-zero if unbuffered
mode is enabled.
-
-
EL_GETFP
,
int fd, FILE **fp
- Set fp to the current
editline file pointer for “input”
fd =
0
,
“output” fd =
1
, or “error”
fd = 2
.
-
-
- el_source()
- Initialize editline by reading the
contents of file. el_parse() is
called for each line in file. If
file is
NULL
, try
$EDITRC and if that is not set
$HOME/.editrc. Refer to
editrc(5) for details on the
format of file. el_source()
returns 0 on success and -1 on error.
-
-
- el_resize()
- Must be called if the terminal size changes. If
EL_SIGNAL
has been set with
el_set(), then this is done automatically. Otherwise,
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
LineInfo 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 functions 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()
- Initialize the history list, and return a data structure to
be used by all other history list functions, or
NULL
on failure.
-
-
- 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 arguments 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, history_gfun_t
first, history_gfun_t next,
history_gfun_t last,
history_gfun_t prev,
history_gfun_t curr,
history_sfun_t set, history_vfun_t
clear, history_efun_t enter,
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. It is newer
than the current one.
-
-
H_NEXT
- Return the next element in the history. It is older
than the current one.
-
-
H_CURR
- Return the current element in the history.
-
-
H_SET
,
int position
- Set the cursor to point to the requested element.
-
-
H_ADD
,
const char *str
- Append str to the current element
of the history, or perform 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 necessary, removing the oldest entry to keep the list
to the created size. If
H_SETUNIQUE
has been
called with a non-zero argument, 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_SAVE_FP
,
FILE *fp
- Save the history list to the opened
FILE pointer fp.
-
-
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
elements should be entered into the history.
-
-
H_DEL
,
int e
- Delete the event numbered e. This
function is only provided for
readline(3)
compatibility. The caller is responsible for free'ing the string in
the returned HistEvent.
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()
- Initialize 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
successfully 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 indicates 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 ALSO
sh(1),
signal(3),
termcap(3),
editrc(5),
termcap(5),
editline(7)
HISTORY
The
editline library first appeared in
4.4BSD.
CC_REDISPLAY
appeared
in
NetBSD 1.3.
CC_REFRESH_BEEP
,
EL_EDITMODE
and the readline emulation appeared in
NetBSD 1.4.
EL_RPROMPT
appeared in
NetBSD
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 readline 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.