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.\" Copyright 2018-2023,2024 Thomas E. Dickey                                *
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.\" Author: Thomas E. Dickey 2003
.\"
.\" $Id: key_defined.3x,v 1.38 2024/06/08 23:25:34 tom Exp $
.TH key_defined 3X 2024-06-08 "ncurses @NCURSES_MAJOR@.@NCURSES_MINOR@" "Library calls"
.SH NAME
\fB\%key_defined\fP \-
test whether a \fIcurses\fP function key code is defined
.SH SYNOPSIS
.nf
\fB#include <curses.h>
.PP
\fBint key_defined(const char * \fIdefinition\fP);
.fi
.SH DESCRIPTION
The
.B \%key_defined
.I \%ncurses
extension permits a
.I curses
application to determine the function key code,
if any,
to which the string
.I definition
is bound.
.SH RETURN VALUE
.B \%key_defined
returns the first key code to which
.I definition
is bound if any exists.
If none does,
it returns
.BR 0 "."
If
.I definition
is a prefix of another binding,
.B \%key_defined
returns
.BR \-1 "."
.SH EXTENSIONS
.B \%define_key
is an
.I \%ncurses
extension.
.SH PORTABILITY
Applications employing
.I \%ncurses
extensions should condition their use on the visibility of the
.B \%NCURSES_VERSION
preprocessor macro.
.SH AUTHORS
Thomas Dickey
.SH SEE ALSO
\fB\%curses\fP(3X),
\fB\%define_key\fP(3X),
\fB\%keybound\fP(3X),
\fB\%keyok\fP(3X)