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.
+ current or specified window. In no-delay mode, if no in-
+ put 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 new-
+ line (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.
@@ -85,44 +82,53 @@
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
+ 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 func-
+ tion key value. For this reason, many terminals experi-
+ ence 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 char-
+ acters. Their names begin with KEY_.
+
+ o Other (user-defined) function keys which may be de-
+ fined 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
+ character is guaranteed. If the program 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
+
+ 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,
+ 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.
+ the same time. Depending on the state of the tty driver
+ when each character is typed, the program may produce un-
+ desirable 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
@@ -132,20 +138,28 @@
Upon successful completion, unget_wch returns OK. Other-
wise, the function 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.
-