- get_wch, wget_wch, mvget_wch, mvwget_wch, unget_wch - get
- (or push back) a wide character from curses terminal key-
- board
+ get_wch, wget_wch, mvget_wch, mvwget_wch, unget_wch - get (or push
+ back) a wide character from curses terminal keyboard
- 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 char-
- acter 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 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.
+
+
+ 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.
+
+ Unlike ungetch and wgetch, unget_wch cannot distinguish special charac-
+ ters returned by wget_wch from ordinary characters. An application 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>.
+ 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.
+ 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.
+ 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.
- When get_wch, wget_wch, mvget_wch, and mvwget_wch func-
- tions 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.
+ 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. Other-
- wise, the function returns ERR.
+ Upon successful completion, unget_wch returns OK. Otherwise, the func-
+ tion returns ERR.
- Functions with a "mv" prefix first perform a cursor move-
- ment using wmove, and return an error if the position is
- outside the window, or if the window pointer is null.
+ 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.