curs_get_wch(3) UNIX Programmer's Manual curs_get_wch(3)
get_wch, wget_wch, mvget_wch, mvwget_wch, unget_wch - get
(or push back) a wide character from curses terminal key-
board
#include <curses.h>
int get_wch(wint_t *wch);
int wget_wch(WINDOW *win, wint_t *wch);
int mvget_wch(int y, int x, wint_t *wch);
int mvwget_wch(WINDOW *win, int y, int x, wint_t *wch);
int unget_wch(const wchar_t wch);
The get_wch, wget_wch, mvget_wch, and mvwget_wch functions
read a character from the terminal associated with the
current or specified window. In no-delay mode, if no input
is waiting, the value ERR is returned. In delay mode, the
program waits until the system passes text through to the
program. Depending on the setting of cbreak, this is after
one character (cbreak mode), or after the first newline
(nocbreak mode). In half-delay mode, the program waits until
the user types a character or the specified timeout interval
has elapsed.
Unless noecho has been set, these routines echo the charac-
ter into the designated window.
If the window is not a pad and has been moved or modified
since the last call to wrefresh, wrefresh will be called
before another character is read.
If keypad is enabled, these functions respond to the press-
ing of a function key by setting the object pointed to by
wch to the corresponding KEY_ value defined in <curses.h>
and returning KEY_CODE_YES. If a character (such as escape)
that could be the beginning of a function key is received,
curses sets a timer. If the remainder of the sequence does
arrive within the designated time, curses passes through the
character; otherwise, curses returns the function key value.
For this reason, many terminals experience a delay between
the time a user presses the escape key and the time the
escape is returned to the program.
The unget_wch function pushes the wide character wch back
onto the head of the input queue, so the wide character is
returned by the next call to get_wch. The pushback of one
character is guaranteed. If the program calls unget_wch too
many times without an intervening call to get_wch, the
operation may fail.
MirBSD #10-current Printed 2022-12-23 1
curs_get_wch(3) UNIX Programmer's Manual curs_get_wch(3)
The header file <curses.h> automatically includes the header
file <stdio.h>.
Applications should not define the escape key by itself as a
single-character function.
When using get_wch, wget_wch, mvget_wch, or mvwget_wch,
applications should not use nocbreak mode and echo mode at
the same time. Depending on the state of the tty driver when
each character is typed, the program may produce undesirable
results.
All functions except wget_wch and unget_wch may be macros.
When get_wch, wget_wch, mvget_wch, and mvwget_wch functions
successfully report the pressing of a function key, they
return KEY_CODE_YES. When they successfully report a wide
character, they return OK. Otherwise, they return ERR.
Upon successful completion, unget_wch returns OK. Otherwise,
the function returns ERR.
curses(3), curs_getch(3), curs_ins_wch(3), curs_inopts(3),
curs_move(3), curs_refresh(3)
MirBSD #10-current Printed 2022-12-23 2