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'\" t
.\"***************************************************************************
.\" Copyright 2018-2023,2024 Thomas E. Dickey                                *
.\" Copyright 1998-2010,2017 Free Software Foundation, Inc.                  *
.\"                                                                          *
.\" Permission is hereby granted, free of charge, to any person obtaining a  *
.\" copy of this software and associated documentation files (the            *
.\" "Software"), to deal in the Software without restriction, including      *
.\" without limitation the rights to use, copy, modify, merge, publish,      *
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.\" furnished to do so, subject to the following conditions:                 *
.\"                                                                          *
.\" The above copyright notice and this permission notice shall be included  *
.\" in all copies or substantial portions of the Software.                   *
.\"                                                                          *
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.\" OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
.\" IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
.\" DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
.\" OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
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.\"
.\" $Id: curs_inch.3x,v 1.44 2024/01/13 22:05:39 tom Exp $
.TH curs_inch 3X 2024-01-13 "ncurses 6.4" "Library calls"
.ie \n(.g \{\
.ds `` \(lq
.ds '' \(rq
.\}
.el \{\
.ie t .ds `` ``
.el   .ds `` ""
.ie t .ds '' ''
.el   .ds '' ""
.\}
.
.de bP
.ie n  .IP \(bu 4
.el    .IP \(bu 2
..
.SH NAME
\fB\%inch\fP,
\fB\%winch\fP,
\fB\%mvinch\fP,
\fB\%mvwinch\fP \-
get a \fIcurses\fR character from a window
.SH SYNOPSIS
.nf
\fB#include <curses.h>
.PP
\fBchtype inch(void);
\fBchtype winch(WINDOW *\fIwin\fP);
.PP
\fBchtype mvinch(int \fIy\fP, int \fIx\fP);
\fBchtype mvwinch(WINDOW *\fIwin\fP, int \fIy\fP, int \fIx\fP);
.fi
.SH DESCRIPTION
These routines return the character, of type \fBchtype\fP, at the current
position in the named window.
If any attributes are set for that position,
their values are OR'ed into the value returned.
Constants defined in
\fB<curses.h>\fP can be used with the \fB&\fP (logical AND) operator to
extract the character or attributes alone.
.
.SS Attributes
The following bit masks may be AND-ed with characters returned by \fBwinch\fP.
.PP
.TS
Lb Lb
Lb Lx.
Name	Description
_
A_CHARTEXT	Extract character
A_ATTRIBUTES	Extract attributes
A_COLOR	Extract color pair information
.TE
.SH RETURN VALUE
Functions with a \*(``mv\*('' prefix first perform a cursor movement using
\fBwmove\fP, and return an error if the position is outside the window,
or if the window pointer is null.
.PP
The \fBwinch\fP function does not return an error if the window contains
characters larger than 8-bits (255).
Only the low-order 8 bits of the character are used by \fBwinch\fP.
.SH NOTES
Note that all of these routines may be macros.
.SH PORTABILITY
These functions are described in the XSI Curses standard, Issue 4.
.PP
Very old systems (before standardization) provide a different function
with the same name:
.bP
The \fBwinch\fP function was part of the original BSD curses library,
which stored a 7-bit character combined with the \fIstandout\fP attribute.
.IP
In BSD curses, \fBwinch\fP returned only the character (as an integer)
with the \fIstandout\fP attribute removed.
.bP
System V curses added support for several video attributes which
could be combined with characters in the window.
.IP
Reflecting this improvement, the function was altered to return the
character combined with all video attributes in a \fBchtype\fP value.
.PP
X/Open Curses does not specify
the size and layout of attributes, color and character values in
\fBchtype\fP; it is implementation-dependent.
This implementation uses 8 bits for character values.
An application using more bits, e.g., a Unicode value,
should use the wide-character equivalents to these functions.
.SH SEE ALSO
.TP
\fB\%curses\fP(3X)
gives an overview of the \fB\%WINDOW\fP and \fB\%chtype\fP data types.
.TP
\fB\%curs_attr\fP(3X)
goes into more detail, pointing out portability problems and
constraints on the use of \fB\%chtype\fP for returning window
information.
.TP
\fB\%curs_in_wch\fP(3X)
describes comparable functions for the wide-character (ncursesw)
library.