'\" t
.\"***************************************************************************
-.\" Copyright (c) 1998-2006,2010 Free Software Foundation, Inc. *
+.\" 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 *
.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: curs_inch.3x,v 1.16 2010/08/14 23:35:36 tom Exp $
-.TH curs_inch 3X ""
+.\" $Id: curs_inch.3x,v 1.51 2024/04/20 21:20:07 tom Exp $
+.TH curs_inch 3X 2024-04-20 "ncurses @NCURSES_MAJOR@.@NCURSES_MINOR@" "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
-\fBinch\fR,
-\fBwinch\fR,
-\fBmvinch\fR,
-\fBmvwinch\fR \- get a character and attributes from a \fBcurses\fR window
+\fB\%inch\fP,
+\fB\%winch\fP,
+\fB\%mvinch\fP,
+\fB\%mvwinch\fP \-
+get a \fIcurses\fR character from a window
.SH SYNOPSIS
-\fB#include <curses.h>\fR
-.sp
-\fBchtype inch(void);\fR
-.br
-\fBchtype winch(WINDOW *win);\fR
-.br
-\fBchtype mvinch(int y, int x);\fR
-.br
-\fBchtype mvwinch(WINDOW *win, int y, int x);\fR
-.br
+.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\fR, 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>\fR can be used with the \fB&\fR (logical AND) operator to
+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\fR.
-.
+The following bit masks may be AND-ed with characters returned by \fBwinch\fP.
+.PP
.TS
-l l .
-\fBA_CHARTEXT\fR Bit-mask to extract character
-\fBA_ATTRIBUTES\fR Bit-mask to extract attributes
-\fBA_COLOR\fR Bit-mask to extract color-pair field information
+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.
+Functions prefixed with \*(``mv\*('' first perform cursor movement and
+fail if the position
+.RI ( y ,
+.IR x )
+is outside the window boundaries.
+.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.
+These functions are described in X/Open Curses, 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
-\fBcurses\fR(3X).
+\fB\%curs_in_wch\fP(3X) describes comparable functions of the
+.I \%ncurses
+library in its wide-character configuration
+.RI ( \%ncursesw ).
.PP
-Comparable functions in the wide-character (ncursesw) library are
-described in
-\fBcurs_in_wch\fR(3X).
-.\"#
-.\"# The following sets edit modes for GNU EMACS
-.\"# Local Variables:
-.\"# mode:nroff
-.\"# fill-column:79
-.\"# End:
+\fB\%curses\fP(3X),
+\fB\%curs_instr\fP(3X)
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