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NAME | SYNOPSIS | DESCRIPTION | NOTES | RETURN VALUE | SEE ALSO | COLOPHON |
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curs_get_wch(3X) curs_get_wch(3X)
get_wch, wget_wch, mvget_wch, mvwget_wch, unget_wch - get (or push
back) a wide character from curses terminal keyboard
#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);
wget_wch
The get_wch, wget_wch, mvget_wch, and mvwget_wch functions read a
character from the terminal associated with the current or speci‐
fied window. In no-delay mode, if no input is waiting, the value
ERR is returned. In delay mode, the program waits until the sys‐
tem 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 character 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 pressing of a
function key by setting the object pointed to by wch to the key‐
code assigned to the function key, 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 func‐
tion key value. For this reason, many terminals experience a de‐
lay between the time a user presses the escape key and the time
the escape is returned to the program.
The keycodes returned by these functions are the same as those re‐
turned by wgetch:
• The predefined function keys are listed in <curses.h> as
macros with values outside the range of 8-bit characters.
Their names begin with KEY_.
• Other (user-defined) function keys which may be defined using
define_key(3X) have no names, but also are expected to have
values outside the range of 8-bit characters.
unget_wch
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 guaran‐
teed. If the program calls unget_wch too many times without an
intervening call to get_wch, the operation may fail.
Unlike ungetch and wgetch, unget_wch cannot distinguish special
characters returned by wget_wch from ordinary characters. An ap‐
plication can push special keys which it may read via wget_wch by
checking for the KEY_CODE_YES result, and using ungetch for those
special keys.
The header file <curses.h> automatically includes the header file
<stdio.h>.
Applications should not define the escape key by itself as a sin‐
gle-character function.
When using get_wch, wget_wch, mvget_wch, or mvwget_wch, applica‐
tions 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 suc‐
cessfully 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.
Functions with a “mv” prefix first perform a cursor movement using
wmove, and return an error if the position is outside the window,
or if the window pointer is null.
curses(3X), curs_getch(3X), curs_ins_wch(3X), curs_inopts(3X),
curs_move(3X), curs_refresh(3X)
This page is part of the ncurses (new curses) project. Informa‐
tion about the project can be found at
⟨https://www.gnu.org/software/ncurses/ncurses.html⟩. If you have a
bug report for this manual page, send it to
bug-ncurses-request@gnu.org. This page was obtained from the
project's upstream Git mirror of the CVS repository
⟨https://github.com/mirror/ncurses.git⟩ on 2025-08-11. (At that
time, the date of the most recent commit that was found in the
repository was 2023-03-12.) If you discover any rendering
problems in this HTML version of the page, or you believe there is
a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
man-pages@man7.org
curs_get_wch(3X)
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HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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