curs_get_wch(3) Library Functions Manual curs_get_wch(3)
NAME
curs_get_wch, 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(
win_t *wch ); int wget_wch(
WINDOW *win,
win_t *wch ); int mvget_wch(
int y,
int x,
win_t *wch ); int mvwget_wch(
WINDOW *win,
int y,
int x,
win_t *wch ); int unget_wch(
const wchar_t wch );
LIBRARY
Curses Library (libcurses)
STANDARDS
Interfaces documented on this reference page conform to industry standards as follows:
get_wch, wget_wch, mvget_wch, mvwget_wch, unget_wch: XCURSES4.2
Refer to the standards(5) reference page for more information about industry standards and associated tags.
DESCRIPTION
The get_wch, wget_wch, mvget_wch, and mvwget_wch functions read a character from the terminal associated with the current or specified win-
dow. In no-delay mode, if no input is waiting, these functions return ERR. In delay mode, the program waits until the system passes text
through to the program. Depending on the setting of cbreak, the program waits until it receives one character (in cbreak mode) or the first
newline (in 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 is 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 correspond-
ing 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.
Function Keys
The following function keys, defined in <curses.h>, may be returned by get_wch and related functions if keypad has been enabled. Note that
a particular terminal may not support all of these function keys. In other words, the routines do not return a function key 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 database,
------------------------------------------------------------------------------
Name Key name
------------------------------------------------------------------------------
KEY_BREAK Break key
The four arrow keys
KEY_DOWN
KEY_UP
KEY_LEFT
KEY_RIGHT
KEY_HOME Home key (upward+left arrow)
KEY_BACKSPACE Backspace
KEY_F0 Function keys; space for 64 keys is reserved.
KEY_F(n) For 0 <= n <= 63
KEY_DL Delete line
KEY_IL Insert line
KEY_DC Delete character
KEY_IC Insert char or enter insert mode
KEY_EIC Exit insert char mode
KEY_CLEAR Clear screen
KEY_EOS Clear to end-of-screen
KEY_EOL Clear to end-of-line
KEY_SF Scroll one line forward
KEY_SR Scroll one line backward (in reverse)
KEY_NPAGE Next page
KEY_PPAGE Previous page
KEY_STAB Set tab
KEY_CTAB Clear tab
KEY_CATAB Clear all tabs
KEY_ENTER Enter or send
KEY_SRESET Soft (partial) reset
KEY_RESET Reset or hard reset
KEY_PRINT Print or copy
KEY_LL Home down or bottom (lower left). The keypad is arranged
like this:
A1 up A3
left B2 right
C1 down C3
KEY_A1 Upper left of keypad
KEY_A3 Upper right of keypad
KEY_B2 Center of keypad
KEY_C1 Lower left of keypad
KEY_C3 Lower right of keypad
KEY_BTAB Back tab key
KEY_BEG Beg(inning) key
KEY_CANCEL Cancel key
KEY_CLOSE Close key
KEY_COMMAND Cmd (command) key
KEY_COPY Copy key
KEY_CREATE Create key
KEY_END End key
KEY_EXIT Exit key
KEY_FIND Find key
KEY_HELP Help key
KEY_MARK Mark key
KEY_MESSAGE Message key
KEY_MOVE Move key
KEY_NEXT Next object key
KEY_OPEN Open key
KEY_OPTIONS Options key
KEY_PREVIOUS Previous object key
KEY_REDO Redo key
KEY_REFERENCE Ref(erence) key
KEY_REFRESH Refresh key
KEY_REPLACE Replace key
KEY_RESTART Restart key
KEY_RESUME Resume key
KEY_SAVE Save key
KEY_SBEG Shifted beginning key
KEY_SCANCEL Shifted cancel key
KEY_SCOMMAND Shifted command key
KEY_SCOPY Shifted copy key
KEY_SCREATE Shifted create key
KEY_SDC Shifted delete character key
KEY_SDL Shifted delete line key
KEY_SELECT Select key
KEY_SEND Shifted end key
KEY_SEOL Shifted clear line key
KEY_SEXIT Shifted exit key
KEY_SFIND Shifted find key
KEY_SHELP Shifted help key
KEY_SHOME Shifted home key
KEY_SIC Shifted input key
KEY_SLEFT Shifted left-arrow key
KEY_SMESSAGE Shifted message key
KEY_SMOVE Shifted move key
KEY_SNEXT Shifted next key
KEY_SOPTIONS Shifted options key
KEY_SPREVIOUS Shifted previous key
KEY_SPRINT Shifted print key
KEY_SREDO Shifted redo key
KEY_SREPLACE Shifted replace key
KEY_SRIGHT Shifted right-arrow key
KEY_SRSUME Shifted resume key
KEY_SSAVE Shifted save key
KEY_SSUSPEND Shifted suspend key
KEY_SUNDO Shifted undo key
KEY_SUSPEND Suspend key
KEY_UNDO Undo key
------------------------------------------------------------------------------
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 program may produce undesirable results.
Note that get_wch, mvget_wch, and mvwget_wch may be macros.
RETURN VALUES
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.
SEE ALSO
Functions: curses(3), curs_ins_wch(3), curs_inopts(3), curs_move(3), curs_refresh(3)
Others: standards(5)
curs_get_wch(3)