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
*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 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
.
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
()
- 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 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_getc
()
- Read a character from the tty. ch is
modified to contain the character read. Returns the number of characters
read if successful, -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 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.
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.
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
,
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
“EL_BUILTIN_GETCFN
”.
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
- 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 *),
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,
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
“
EL_BUILTIN_GETCFN
”
in the case of the default builtin function.
EL_CLIENTDATA
,
void **data
- Retrieve data previously registered
with the corresponding
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, 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. 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
()
- 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 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.
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 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
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 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
()
- 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 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)
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.