curs_getch, getch, wgetch, mvgetch, mvwgetch, ungetch - Get (or push back) characters from a Curses terminal keyboard
Curses Library (libcurses)
Interfaces documented on this reference page conform to industry standards as follows:
getch, wgetch, mvgetch, mvwgetch: XPG4, XPG4-UNIX
Refer to the
reference page for more information
about industry standards and associated tags.
The getch, wgetch, mvgetch, and mvwgetch routines read a character from the terminal associated with the Curses window. In no-delay mode, if no input is waiting, these routines return the value ERR. In delay mode, the program waits until the system passes text through to the program. In cbreak mode, the program waits until after one character. In nocbreak mode, the program waits until after the first newline. 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 is also be echoed 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 TRUE and the user presses a function key, Curses returns the token for that function key is returned instead of the raw characters. The <curses.h> file defines possible function keys with integers beginning with 0401 and names beginning with KEY_. If these routines receive a character (such as escape) that could be the beginning of a function key, Curses sets a timer. If the remainder of the sequence does not come in within the designated time, the routines pass the character to the application; otherwise, they return the value for the function key. 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. Since tokens returned by these routines are outside the ASCII range, the tokens are not printable.
back onto the input queue to be returned by the next call to
The following function keys, defined in <curses.h>, might be returned by the *getch functions if keypad has been enabled. All of these keys may not be supported on a particular terminal. 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.
KEY_DOWN KEY_UP KEY_LEFT KEY_RIGHT
|The four arrow keys|
|KEY_HOME||Home key (upward+left arrow)|
|KEY_F0||Function keys; space for 64 keys is reserved.|
|KEY_F(n)||For 0 <= n <= 63|
|KEY_IC||Insert char or enter insert mode|
|KEY_EIC||Exit insert char mode|
|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_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|
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_COMMAND||Cmd (command) key|
|KEY_NEXT||Next object key|
|KEY_PREVIOUS||Previous object 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_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|
The header file <curses.h> automatically includes the header file <stdio.h>.
Programmers should not use the escape key for a single-character function.
When using getch, wgetch, mvgetch, or mvwgetch, 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.
[Compaq] If the ESCDELAY environment variable is set, these functions wait for the specified time period between the escape and following key sequence that indicate a function key. Setting this delay time is useful when function-key sequences are being transferred over a slow network. However, the ESCDELAY environment variable is non-standard, so portable applications should not depend on its availability.
may be macros.
All routines return the integer
upon successful completion.
Functions: curses(3), curs_inopts(3), curs_move(3), curs_refresh(3)