.\"***************************************************************************
-.\" Copyright (c) 1998-2010,2015 Free Software Foundation, Inc. *
+.\" Copyright 2018-2023,2024 Thomas E. Dickey *
+.\" Copyright 1998-2015,2017 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_touch.3x,v 1.16 2015/12/05 23:43:00 tom Exp $
-.TH curs_touch 3X ""
-.na
-.hy 0
+.\" $Id: curs_touch.3x,v 1.47 2024/04/20 21:20:07 tom Exp $
+.TH curs_touch 3X 2024-04-20 "ncurses @NCURSES_MAJOR@.@NCURSES_MINOR@" "Library calls"
.SH NAME
-\fBtouchwin\fR,
-\fBtouchline\fR,
-\fBuntouchwin\fR,
-\fBwtouchln\fR,
-\fBis_linetouched\fR,
-\fBis_wintouched\fR \- \fBcurses\fR refresh control routines
-.ad
-.hy
+\fB\%touchwin\fP,
+\fB\%touchline\fP,
+\fB\%untouchwin\fP,
+\fB\%wtouchln\fP,
+\fB\%is_linetouched\fP,
+\fB\%is_wintouched\fP \-
+control terminal output refresh in a \fIcurses\fR window
.SH SYNOPSIS
-\fB#include <curses.h>\fR
-.br
-\fBint touchwin(WINDOW *win);\fR
-.br
-\fBint touchline(WINDOW *win, int start, int count);\fR
-.br
-\fBint untouchwin(WINDOW *win);\fR
-.br
-\fBint wtouchln(WINDOW *win, int y, int n, int changed);\fR
-.br
-\fBbool is_linetouched(WINDOW *win, int line);\fR
-.br
-\fBbool is_wintouched(WINDOW *win);\fR
-.br
+.nf
+\fB#include <curses.h>
+.PP
+\fBint touchline(WINDOW *\fIwin\fP, int \fIstart\fP, int \fIcount\fP);
+.PP
+\fBint touchwin(WINDOW *\fIwin\fP);
+\fBint wtouchln(WINDOW *\fIwin\fP, int \fIy\fP, int \fIn\fP, int \fIchanged\fP);
+.PP
+\fBint untouchwin(WINDOW *\fIwin\fP);
+.PP
+\fBbool is_linetouched(WINDOW *\fIwin\fP, int \fIline\fP);
+\fBbool is_wintouched(WINDOW *\fIwin\fP);
+.fi
.SH DESCRIPTION
-The \fBtouchwin\fR and \fBtouchline\fR routines throw away all
+The \fB\%touchwin\fP and \fB\%touchline\fP routines throw away all
optimization information about which parts of the window have been
-touched, by pretending that the entire window has been drawn on. This
+touched, by pretending that the entire window has been drawn on.
+This
is sometimes necessary when using overlapping windows, since a change
to one window affects the other window, but the records of which lines
-have been changed in the other window do not reflect the change. The
-routine \fBtouchline\fR only pretends that \fIcount\fR lines have been
-changed, beginning with line \fIstart\fR.
+have been changed in the other window do not reflect the change.
+The
+routine \fB\%touchline\fP only pretends that \fIcount\fP lines have been
+changed, beginning with line \fIstart\fP.
.PP
-The \fBuntouchwin\fR routine marks all lines in the window as unchanged since
-the last call to \fBwrefresh\fR.
+The \fB\%untouchwin\fP routine marks all lines in the window as unchanged since
+the last call to \fB\%wrefresh\fP.
.PP
-The \fBwtouchln\fR routine makes \fIn\fR lines in the window, starting
-at line \fIy\fR, look as if they have (\fIchanged\fR\fB=1\fR) or have
-not (\fIchanged\fR\fB=0\fR) been changed since the last call to
-\fBwrefresh\fR.
+The \fB\%wtouchln\fP routine makes \fIn\fP lines in the window, starting
+at line \fIy\fR, look as if they have (\fIchanged\fB=1\fR) or have
+not (\fIchanged\fB=0\fR) been changed since the last call to
+\fB\%wrefresh\fP.
.PP
-The \fBis_linetouched\fR and \fBis_wintouched\fR routines return
-\fBTRUE\fR if the specified line/window was modified since the last
-call to \fBwrefresh\fR; otherwise they return \fBFALSE\fR. In
-addition, \fBis_linetouched\fR returns \fBERR\fR if \fIline\fR is not
+The \fB\%is_linetouched\fP and \fB\%is_wintouched\fP routines return
+\fBTRUE\fP if the specified line/window was modified since the last
+call to \fB\%wrefresh\fP; otherwise they return \fBFALSE\fP. In
+addition, \fB\%is_linetouched\fP returns \fBERR\fP if \fIline\fP is not
valid for the given window.
.SH RETURN VALUE
-All routines return the integer \fBERR\fR upon failure and an integer value
-other than \fBERR\fR upon successful completion, unless otherwise noted in the
+All routines return the integer \fBERR\fP upon failure and an integer value
+other than \fBERR\fP upon successful completion, unless otherwise noted in the
preceding routine descriptions.
.PP
-X/Open does not define any error conditions.
+X/Open Curses does not specify any error conditions.
In this implementation
-.RS
+.RS 3
.TP 5
\fBis_linetouched\fP
-returns an error
+returns an error
if the window pointer is null, or
-if the line number is outside the window.
-Note that ERR is distinct from \fBTRUE\fP and \fBFALSE\fP, which are the normal return values of this function.
+if the line number is outside the window boundaries.
+.IP
+The constant \fBERR\fP is distinct from \fBTRUE\fP and \fBFALSE\fP,
+which are the normal return values of this function.
+Because the function returns a \fBbool\fP,
+returning \fBERR\fP (which is neither \fBTRUE\fP nor \fBFALSE\fP)
+may not be supported by the compiler.
+.IP
+To provide error-checking and also match the X/Open function prototype,
+the \fBERR\fP is provided by a macro named \fB\%is_linetouched\fP.
+The actual function returns \fBFALSE\fP when it detects an error.
.TP 5
\fBwtouchln\fP
-returns an error
+returns an error
if the window pointer is null, or
-if the line number is outside the window.
+if the line number is outside the window boundaries.
.RE
+.SH NOTES
+All of these routines except \fB\%wtouchln\fP may be macros.
.SH PORTABILITY
-The XSI Curses standard, Issue 4 describes these functions.
+These functions were introduced by SVr4.
+The Solaris \fIcurses\fP header file,
+for instance, defines both an actual function and macro for each.
+The macros give the same result as the actual functions.
+SVr4 \fIcurses\fP does not check the window parameter \fIwin\fP to ensure
+that it is not \fBNULL\fP;
+otherwise this implementation behaves the same as SVr4.
.PP
-Some historic curses implementations had, as an undocumented feature, the
-ability to do the equivalent of \fBclearok(..., 1)\fR by saying
-\fBtouchwin(stdscr)\fR or \fBclear(stdscr)\fR. This will not work under
-ncurses.
-.SH NOTES
-Note that all routines except \fBwtouchln\fR may be macros.
+X/Open Curses, Issue 4 describes these functions,
+but defines no error conditions.
.SH SEE ALSO
-\fBcurses\fR(3X),
-\fBcurs_refresh\fR(3X),
-\fBcurs_variables\fR(3X).
+\fB\%curses\fP(3X),
+\fB\%curs_refresh\fP(3X),
+\fB\%curs_variables\fP(3X)
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