Provided by: libedit-dev_3.1-20191231-1_amd64 bug

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.

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_NSAVE_FP, size_t n, FILE *fp
                 Save the last n history entries 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
                 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(5edit), termcap(5), editline(7edit)

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.