NAME | SYNOPSIS | DESCRIPTION | NOTES | RETURN VALUE | SEE ALSO | COLOPHON

curs_get_wch(3X)                                            curs_get_wch(3X)

NAME         top

       get_wch, wget_wch, mvget_wch, mvwget_wch, unget_wch - get (or push
       back) a wide character from curses terminal keyboard

SYNOPSIS         top

       #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);

DESCRIPTION         top

       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 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 keycode
       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 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 keycodes returned by these functions are the same as those
       returned 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.
       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.

NOTES         top

       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.

RETURN VALUE         top

       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.
       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.

SEE ALSO         top

       curses(3X), curs_getch(3X), curs_ins_wch(3X), curs_inopts(3X),
       curs_move(3X), curs_refresh(3X)

COLOPHON         top

       This page is part of the ncurses (new curses) project.  Information
       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 
       ⟨git://ncurses.scripts.mit.edu/ncurses.git⟩ on 2017-07-05.  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)