.TH curs_getch 3X "" .SH NAME \fBgetch\fR, \fBwgetch\fR, \fBmvgetch\fR, \fBmvwgetch\fR, \fBungetch\fR - get (or push back) characters from \fBcurses\fR terminal keyboard .SH SYNOPSIS \fB#include \fR \fBint getch(void);\fR .br \fBint wgetch(WINDOW *win);\fR .br \fBint mvgetch(int y, int x);\fR .br \fBint mvwgetch(WINDOW *win, int y, int x);\fR .br \fBint ungetch(int ch);\fR .br .SH DESCRIPTION The \fBgetch\fR, \fBwgetch\fR, \fBmvgetch\fR and \fBmvwgetch\fR, routines read a character from the window. In no-delay mode, if no input is waiting, the value \fBERR\fR is returned. In delay mode, the program waits until the system passes text through to the program. Depending on the setting of \fBcbreak\fR, 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. If \fBnoecho\fR has been set, then the character will also be echoed into the designated window according to the following rules: If the character is the current erase character, left arrow, or backspace, the cursor is moved one space to the left and that screen position is erased as if \fBdelch\fR had been called. If the character value is any other \fBKEY_\fR define, the user is alerted with a \fBbeep\fR call. Otherwise the character is simply output to the screen. If the window is not a pad, and it has been moved or modified since the last call to \fBwrefresh\fR, \fBwrefresh\fR will be called before another character is read. If \fBkeypad\fR is \fBTRUE\fR, 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 \fB\fR as macros with values outside the range of 8-bit characters whose names begin with \fBKEY_.\fR Thus, a variable intended to hold the return value of a function key must be of short size or larger. When a character that could be the beginning of a function key is received (which, on modern terminals, means an escape character), \fBcurses\fR 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 \fBungetch\fR routine places \fIch\fR back onto the input queue to be returned by the next call to \fBwgetch\fR. Note that there is, in effect, just one input queue for all windows. .SS Function Keys The following function keys, defined in \fB\fR, might be returned by \fBgetch\fR if \fBkeypad\fR has been enabled. Note that not all of these are necessarily supported on any particular terminal. .nf __________________________________________________________________ \fIName\fR \fIKey\fR \fIname\fR __________________________________________________________________ KEY_BREAK Break key KEY_DOWN The four arrow keys ... 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(\fIn\fR) For 0 \fI<\fR \fIn\fR \fI<\fR 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 1 line forward KEY_SR Scroll 1 line backward (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). Keypad is arranged like this: \fBA1\fR \fBup\fR \fBA3\fR \fBleft\fR \fBB2\fR \fBright\fR \fBC1\fR \fBdown\fR \fBC3\fR 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 char 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 prev key KEY_SPRINT Shifted print key KEY_SREDO Shifted redo key KEY_SREPLACE Shifted replace key KEY_SRIGHT Shifted right arrow 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 .fi .SH RETURN VALUE All routines return the integer \fBERR\fR upon failure and an integer value other than \fBERR\fR" (\fBOK\fR in the case of ungetch()) upon successful completion. .SH NOTES Use of the escape key by a programmer for a single character function is discouraged, as it will cause a delay of up to one second while the keypad code looks for a following function-key sequence. When using \fBgetch\fR, \fBwgetch\fR, \fBmvgetch\fR, or \fBmvwgetch\fR, nocbreak mode (\fBnocbreak\fR) and echo mode (\fBecho\fR) 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 \fBgetch\fR, \fBmvgetch\fR, and \fBmvwgetch\fR may be macros. Historically, the set of keypad macros was largely defined by the extremely function-key-rich keyboard of the AT&T 7300, aka 3B1, aka Safari 4. Modern personal computers usually have only a small subset of these. IBM PC-style consoles typically support little more than \fBKEY_UP\fR, \fBKEY_DOWN\fR, \fBKEY_LEFT\fR, \fBKEY_RIGHT\fR, \fBKEY_HOME\fR, \fBKEY_END\fR, \fBKEY_NPAGE\fR, \fBKEY_PPAGE\fR, and function keys 1 through 12. The Ins key is usually mapped to \fBKEY_IC\fR. .SH PORTABILITY These functions are described in the XSI Curses standard, Issue 4. They read single-byte characters only. The standard specifies that they return \fBERR\fR on failure, but specifies no error conditions. The echo behavior of these functions on input of \fBKEY_\fR or backspace characters was not specified. This description is adopted from the XSI Curses standard. .SH SEE ALSO \fBcurses\fR(3X), \fBcurs_inopts\fR(3X), \fBcurs_move\fR(3X), \fBcurs_refresh\fR(3X). .\"# .\"# The following sets edit modes for GNU EMACS .\"# Local Variables: .\"# mode:nroff .\"# fill-column:79 .\"# End: