.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: curs_getch.3x,v 1.41 2015/07/16 09:29:33 tom Exp $
+.\" $Id: curs_getch.3x,v 1.43 2015/09/19 22:25:05 tom Exp $
.TH curs_getch 3X ""
.na
.hy 0
.PP
\fBint getch(void);\fR
.br
-\fBint wgetch(WINDOW *win);\fR
+\fBint wgetch(WINDOW *\fP\fIwin);\fR
.br
-\fBint mvgetch(int y, int x);\fR
+\fBint mvgetch(int \fP\fIy\fP\fB, int \fP\fIx\fP\fB);\fR
.br
-\fBint mvwgetch(WINDOW *win, int y, int x);\fR
+\fBint mvwgetch(WINDOW *\fP\fIwin\fP\fB, int \fP\fIy\fP\fB, int \fP\fIx\fP\fB);\fR
.br
-\fBint ungetch(int ch);\fR
+\fBint ungetch(int \fP\fIch\fP\fB);\fR
.br
-\fBint has_key(int ch);\fR
+\fBint has_key(int \fP\fIch\fP\fB);\fR
.br
.SH DESCRIPTION
.SS Reading characters
returned by the next call to \fBwgetch\fR.
There is just one input queue for all windows.
.PP
-.SS Function Keys
-The following function keys, defined in \fB<curses.h>\fR, might be returned by
+.SS Predefined key-codes
+The following special keys, defined in \fB<curses.h>\fR, may be returned by
\fBgetch\fR if \fBkeypad\fR has been enabled.
-Note that not all of these are
-necessarily supported on any particular terminal.
+Not all of these are necessarily supported on any particular terminal.
.PP
.TS
center tab(/) ;
.TE
.PP
Keypad is arranged like this:
-.sp
+.br
.TS
center allbox tab(/) ;
c c c .
\fBC1\fR/\fBdown\fR/\fBC3\fR
.TE
.sp
-The \fBhas_key\fR routine takes a key value from the above list, and
+A few of these predefined values do \fInot\fP correspond to a real key:
+.bP
+.B KEY_RESIZE
+is returned when the \fBSIGWINCH\fP signal has been detected
+(see \fBinitscr\fP(3X) and \fBresizeterm\fR(3X)).
+This code is returned whether or not \fBkeypad\fP has been enabled.
+.bP
+.B KEY_MOUSE
+is returned for mouse-events (see \fBcurs_mouse\fR(3X)).
+This code relies upon whether or not \fBkeypad\fP(3X) has been enabled,
+because (e.g., with \fIxterm\fP mouse prototocol) ncurses must
+read escape sequences,
+just like a function key.
+.SS Testing key-codes
+.PP
+The \fBhas_key\fR routine takes a key-code value from the above list, and
returns \fBTRUE\fP or \fBFALSE\fP according to whether
the current terminal type recognizes a key with that value.
-Note that a few values do not correspond to a real key,
-e.g., \fBKEY_RESIZE\fP and \fBKEY_MOUSE\fP.
-See \fBinitscr\fP(3X) and \fBresizeterm\fR(3X) for more details about \fBKEY_RESIZE\fP, and
-\fBcurs_mouse\fR(3X) for a discussion of \fBKEY_MOUSE\fP.
+.PP
+The library also supports these extensions:
+.RS 3
+.TP 5
+.B define_key
+defines a key-code for a given string (see \fBdefine_key\fP(3X)).
+.TP 5
+.B key_defined
+checks if there is a key-code defined for a given
+string (see \fBkey_defined\fP(3X)).
+.RE
.PP
.SH RETURN VALUE
All routines return the integer \fBERR\fR upon failure and an integer value
discouraged, as it will cause a delay of up to one second while the
keypad code looks for a following function-key sequence.
.PP
-Note that some keys may be the same as commonly used control
+Some keys may be the same as commonly used control
keys, e.g., \fBKEY_ENTER\fP versus control/M, \fBKEY_BACKSPACE\fP versus control/H.
Some curses implementations may differ according to whether they
treat these control keys specially (and ignore the terminfo), or
progress or not, and also (in some implementations) depending on whether an
input timeout or non-blocking mode has been set.
.PP
+\fBKEY_MOUSE\fP is mentioned in XSI Curses, along with a few related
+terminfo capabilities, but no higher-level functions use the feature.
+The implementation in ncurses is an extension.
+.PP
+\fBKEY_RESIZE\fP is an extension first implemented for ncurses.
+NetBSD curses later added this extension.
+.PP
Programmers concerned about portability should be prepared for either of two
cases: (a) signal receipt does not interrupt \fBgetch\fR; (b) signal receipt
interrupts \fBgetch\fR and causes it to return ERR with \fBerrno\fR set to
projects / ncurses.git / blobdiff