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curs_get_wch(3X)					      curs_get_wch(3X)

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

SYNOPSIS
       #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
       The get_wch, wget_wch, mvget_wch, and mvwget_wch	functions read a char-
       acter  from  the	terminal associated with the current or	specified win-
       dow.  In	no-delay mode, if no input is waiting, the value  ERR  is  re-
       turned.	 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 as-
       signed 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 re-
       ceived, curses sets a timer.  If	the remainder of the sequence does ar-
       rive  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:

       o   The	predefined  function  keys  are	listed in <curses.h> as	macros
	   with	values outside the range of 8-bit characters.  Their names be-
	   gin with KEY_.

       o   Other  (user-defined)  function keys	which may be defined using de-
	   fine_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 pro-
       gram calls unget_wch too	many times  without  an	 intervening  call  to
       get_wch,	the operation may fail.

NOTES
       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 pro-
       gram may	produce	undesirable results.

       All functions except wget_wch and unget_wch may be macros.

RETURN VALUE
       When get_wch, wget_wch, mvget_wch, and mvwget_wch functions successful-
       ly  report  the	pressing  of a function	key, they return KEY_CODE_YES.
       When they successfully report a wide character, they return OK.	Other-
       wise, they return ERR.

       Upon successful completion, unget_wch returns OK.  Otherwise, the func-
       tion 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
       curses(3X),    curs_getch(3X),	 curs_ins_wch(3X),    curs_inopts(3X),
       curs_move(3X), curs_refresh(3X)

							      curs_get_wch(3X)

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

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