- get (or push back) wchar_t characters from curses terminal keyboard
cc [ flag ... ] file ... -lcurses [ library .. ] #include <curses.h> int getwch(void);
int wgetwch(WINDOW *win);
int mvgetwch(int y, int x);
int mvwgetwch(WINDOW *win, int y, int x);
int ungetwch(int wch);
The getwch(), wgetwch(), mvgetwch(), and mvwgetwch() routines read an EUC character from the terminal associated with the window, transform it into a wchar_t character, and return a wchar_t character. 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 a character is typed or the specified timeout has been reached. Unless noecho has been set, the character will also be echoed into the designated window.
If the window is not a pad, and it has been moved or modified since the last call to wrefresh(3CURSES), wrefresh will be called before another character is read.
If keypad is TRUE, and a function key is pressed, the token for that function key is returned instead of the raw characters. Possible function keys are defined in <curses.h> with integers beginning with 0401, whose names begin with KEY_. If a character that could be the beginning of a function key (such as escape) is received, curses(3CURSES) sets a timer. If the remainder of the sequence does not come in within the designated time, the character is passed through; otherwise, the function key value is returned. For this reason, many terminals experience a delay between the time a user presses the escape key and the escape is returned to the program.
The ungetwch() routine places wch back onto the input queue to be returned by the next call to wgetwch().
The following function keys, defined in <curses.h>, might be returned by getwch() if keypad has been enabled. Note that not all of these may be supported on a particular terminal if the terminal does not transmit a unique code when the key is pressed or if the definition for the key is not present in the terminfo(4) database.
All routines return the integer ERR upon failure and an integer value other than ERR upon successful completion.
See attributes(5) for descriptions of the following attributes:
The header file <curses.h> automatically includes the header files <stdio.h>, <unctrl.h> and <widec.h>.
Use of the escape key by a programmer for a single character function is discouraged.
When using getwch(), wgetwch(), mvgetwch(), or mvwgetwch(), nocbreak mode and echo mode should not be used at the same time. Depending on the state of the tty driver when each character is typed, the program may produce undesirable results.
Note that getwch(), mvgetwch(), and mvwgetwch() may be macros.