ncurses 6.2 - patch 20201003

[ncurses.git] / man / curs_touch.3x

diff --git a/man/curs_touch.3x b/man/curs_touch.3x
index 4856e190b5c845498c9327bf0601cb502b0cbdae..e53207896529db531f2c0e697e729f8ec7785492 100644 (file)
--- a/man/curs_touch.3x
+++ b/man/curs_touch.3x
@@ -1,5 +1,6 @@
 .\"***************************************************************************
 .\"***************************************************************************

-.\" Copyright (c) 1998-2006,2010 Free Software Foundation, Inc.              *
+.\" Copyright 2018,2020 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            *
 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *
 .\" copy of this software and associated documentation files (the            *


@@ -26,7 +27,7 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"

-.\" $Id: curs_touch.3x,v 1.12 2010/07/31 16:10:55 tom Exp $
+.\" $Id: curs_touch.3x,v 1.22 2020/02/02 23:34:34 tom Exp $

 .TH curs_touch 3X ""
 .na
 .hy 0
 .TH curs_touch 3X ""
 .na
 .hy 0


@@ -57,10 +58,12 @@
 .SH DESCRIPTION
 The \fBtouchwin\fR and \fBtouchline\fR routines throw away all
 optimization information about which parts of the window have been
 .SH DESCRIPTION
 The \fBtouchwin\fR and \fBtouchline\fR 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
 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
+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.
 .PP
 routine \fBtouchline\fR only pretends that \fIcount\fR lines have been
 changed, beginning with line \fIstart\fR.
 .PP


@@ -84,13 +87,22 @@ preceding routine descriptions.
 .PP
 X/Open does not define any error conditions.
 In this implementation
 .PP
 X/Open does not define any error conditions.
 In this implementation

-.RS
+.RS 3

 .TP 5
 \fBis_linetouched\fP
 returns an error 
 if the window pointer is null, or
 if the line number is outside the window.
 .TP 5
 \fBis_linetouched\fP
 returns an error 
 if the window pointer is null, or
 if the line number is outside the window.

-Note that ERR is distinct from TRUE and FALSE, which are the normal return values of this function.
+.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 \fBis_linetouched\fP.
+The actual function returns \fBFALSE\fP when it detects an error.

 .TP 5
 \fBwtouchln\fP
 returns an error 
 .TP 5
 \fBwtouchln\fP
 returns an error 


@@ -98,19 +110,20 @@ if the window pointer is null, or
 if the line number is outside the window.
 .RE
 .SH PORTABILITY
 if the line number is outside the window.
 .RE
 .SH PORTABILITY

-The XSI Curses standard, Issue 4 describes these functions.

 .PP
 .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.
+These functions were introduced by SVr4.
+The Solaris curses header file,
+for instance, defines both an actual function and macro for each.
+The macros give the same result as the actual functions.
+SVr4 curses 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
+The XSI Curses standard, Issue 4 describes these functions,
+but defines no error conditions.

 .SH NOTES
 .SH NOTES

-Note that all routines except \fBwtouchln\fR may be macros.
+All of these routines except \fBwtouchln\fR may be macros.

 .SH SEE ALSO
 .SH SEE ALSO

-\fBcurses\fR(3X), \fBcurs_refresh\fR(3X).
-.\"#
-.\"# The following sets edit modes for GNU EMACS
-.\"# Local Variables:
-.\"# mode:nroff
-.\"# fill-column:79
-.\"# End:
+\fBcurses\fR(3X),
+\fBcurs_refresh\fR(3X),
+\fBcurs_variables\fR(3X).