.\"***************************************************************************
-.\" Copyright 2018-2021,2022 Thomas E. Dickey *
+.\" Copyright 2018-2023,2024 Thomas E. Dickey *
.\" Copyright 1998-2016,2017 Free Software Foundation, Inc. *
.\" *
.\" Permission is hereby granted, free of charge, to any person obtaining a *
.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: curs_outopts.3x,v 1.37 2022/02/12 20:05:11 tom Exp $
-.TH curs_outopts 3X 2022-02-12 "ncurses 6.4" "Library calls"
-.na
-.hy 0
+.\" $Id: curs_outopts.3x,v 1.64 2024/04/20 21:24:19 tom Exp $
+.TH curs_outopts 3X 2024-04-20 "ncurses @NCURSES_MAJOR@.@NCURSES_MINOR@" "Library calls"
.de bP
.ie n .IP \(bu 4
.el .IP \(bu 2
..
.SH NAME
-\fBclearok\fP,
-\fBidlok\fP,
-\fBidcok\fP,
-\fBimmedok\fP,
-\fBleaveok\fP,
-\fBsetscrreg\fP,
-\fBwsetscrreg\fP,
-\fBscrollok\fP \- \fBcurses\fP output options
-.ad
-.hy
+\fB\%clearok\fP,
+\fB\%idlok\fP,
+\fB\%idcok\fP,
+\fB\%immedok\fP,
+\fB\%leaveok\fP,
+\fB\%setscrreg\fP,
+\fB\%wsetscrreg\fP,
+\fB\%scrollok\fP \-
+set \fIcurses\fR output options
.SH SYNOPSIS
-\fB#include <curses.h>\fP
-.sp
-\fBint clearok(WINDOW *\fIwin\fB, bool \fIbf\fB);\fR
-.br
-\fBint idlok(WINDOW *\fIwin\fB, bool \fIbf\fB);\fR
-.br
-\fBvoid idcok(WINDOW *\fIwin\fB, bool \fIbf\fB);\fR
-.br
-\fBvoid immedok(WINDOW *\fIwin\fB, bool \fIbf\fB);\fR
-.br
-\fBint leaveok(WINDOW *\fIwin\fB, bool \fIbf\fB);\fR
-.br
-\fBint scrollok(WINDOW *\fIwin\fB, bool \fIbf\fB);\fR
-.sp
-\fBint setscrreg(int \fItop\fB, int \fIbot\fB);\fR
-.br
-\fBint wsetscrreg(WINDOW *\fIwin\fB, int \fItop\fB, int \fIbot\fB);\fR
-.br
+.nf
+\fB#include <curses.h>
+.PP
+\fBint clearok(WINDOW *\fIwin\fP, bool \fIbf\fP);
+\fBint idlok(WINDOW *\fIwin\fP, bool \fIbf\fP);
+\fBvoid idcok(WINDOW *\fIwin\fP, bool \fIbf\fP);
+\fBvoid immedok(WINDOW *\fIwin\fP, bool \fIbf\fP);
+\fBint leaveok(WINDOW *\fIwin\fP, bool \fIbf\fP);
+\fBint scrollok(WINDOW *\fIwin\fP, bool \fIbf\fP);
+.PP
+\fBint setscrreg(int \fItop\fP, int \fIbot\fP);
+\fBint wsetscrreg(WINDOW *\fIwin\fP, int \fItop\fP, int \fIbot\fP);
+.fi
.SH DESCRIPTION
-.PP
These routines set options that change the style of output within
\fBcurses\fP.
All options are initially \fBFALSE\fP, unless otherwise stated.
It is not necessary to turn these options off before calling \fBendwin\fP(3X).
.SS clearok
-.PP
If \fBclearok\fP is called with \fBTRUE\fP as argument, the next
call to \fBwrefresh\fP with this window will clear the screen completely and
redraw the entire screen from scratch.
the next call to \fBwrefresh\fP with any window causes the screen to be cleared
and repainted from scratch.
.SS idlok
-.PP
If \fBidlok\fP is called with \fBTRUE\fP as second argument, \fBcurses\fP
considers using the hardware insert/delete line feature of terminals so
equipped.
If insert/delete line
cannot be used, \fBcurses\fP redraws the changed portions of all lines.
.SS idcok
-.PP
If \fBidcok\fP is called with \fBFALSE\fP as second argument, \fBcurses\fP
no longer considers using the hardware insert/delete character feature of
terminals so equipped.
Calling \fBidcok\fP with \fBTRUE\fP as second argument re-enables use
of character insertion and deletion.
.SS immedok
-.PP
-If \fBimmedok\fP is called with \fBTRUE as argument\fP, any change
-in the window image, such as the ones caused by \fBwaddch, wclrtobot, wscrl\fP,
-etc., automatically cause a call to \fBwrefresh\fP.
-However, it may
-degrade performance considerably, due to repeated calls to \fBwrefresh\fP.
-It is disabled by default.
+If \fBimmedok\fP is called with \fBTRUE\fP as second argument,
+any change in the window image,
+such as the ones caused by \fBwaddch, wclrtobot, wscrl\fP,
+etc., automatically causes a call to \fBwrefresh\fP.
+However, it may degrade performance considerably,
+due to repeated calls to \fBwrefresh\fP.
+Calling \fBimmedok\fP with \fBFALSE\fP as second argument
+restores the default behavior,
+i.e., deferring screen updates until a refresh is needed.
.SS leaveok
-.PP
Normally, the hardware cursor is left at the location of the window cursor
being refreshed.
The \fBleaveok\fP option allows the cursor to be left
It is useful for applications where
the cursor is not used, since it reduces the need for cursor motions.
.SS scrollok
-.PP
The \fBscrollok\fP option controls what happens when the cursor of a window is
moved off the edge of the window or scrolling region, either as a result of a
newline action on the bottom line, or typing the last character of the last
If enabled, (\fIbf\fP is \fBTRUE\fP), the window is scrolled up one line
(Note that to get the physical scrolling effect on the terminal, it is
also necessary to call \fBidlok\fP).
-.SS setscrreg/wsetscrreg
-.PP
+.SS "setscrreg, wsetscrreg"
The \fBsetscrreg\fP and \fBwsetscrreg\fP routines allow the application
programmer to set a software scrolling region in a window.
The \fItop\fP and
All other routines that return an integer always
return \fBOK\fP.
.PP
-X/Open Curses does not define any error conditions.
+X/Open Curses does not specify any error conditions.
.PP
In this implementation,
.bP
will return an error if the window pointer is null
.bP
\fBwsetscrreg\fP
-returns an error if the scrolling region limits extend outside the window.
-.RE
+returns an error if the scrolling region limits extend outside the
+window boundaries.
+.SH NOTES
+Note that
+\fBclearok\fP,
+\fBleaveok\fP,
+\fBscrollok\fP,
+\fBidcok\fP, and
+\fBsetscrreg\fP may be macros.
.PP
-X/Open does not define any error conditions.
-This implementation returns an error
-if the window pointer is null.
+The \fBimmedok\fP routine is useful for windows that are used as terminal
+emulators.
.SH PORTABILITY
-These functions are described in the XSI Curses standard, Issue 4.
-.PP
-From the outset, ncurses used \fBnl\fP/\fBnonl\fP to control the conversion
-of newlines to carriage return/line-feed on output as well as input.
-XSI Curses documents only the use of these functions for input.
-This difference arose from converting the \fIpcurses\fP source
-(which used \fBioctl\fP calls with the \fBsgttyb\fP structure)
-to termios (i.e., the POSIX terminal interface).
-In the former, both input and output were controlled via a single
-option \fBCRMOD\fP,
-while the latter separates these features.
-Because that conversion interferes with output optimization,
-\fBnl\fP/\fBnonl\fP were amended after ncurses 6.2
-to eliminate their effect on output.
+These functions are described in X/Open Curses, Issue 4.
.PP
Some historic curses implementations had, as an undocumented feature, the
ability to do the equivalent of \fBclearok(..., 1)\fP by saying
\fBtouchwin(stdscr)\fP or \fBclear(stdscr)\fP.
-This will not work under ncurses.
+This will not work under \fI\%ncurses\fP.
.PP
Earlier System V curses implementations specified that with \fBscrollok\fP
enabled, any window modification triggering a scroll also forced a physical
refresh.
-XSI Curses does not require this, and \fBncurses\fP avoids doing
+X/Open Curses does not require this, and \fI\%ncurses\fP avoids doing
it to perform better vertical-motion optimization at \fBwrefresh\fP
time.
.PP
-The XSI Curses standard does not mention that the cursor should be
+X/Open Curses does not mention that the cursor should be
made invisible as a side-effect of \fBleaveok\fP.
SVr4 curses documentation does this, but the code does not.
Use \fBcurs_set\fP to make the cursor invisible.
-.SH NOTES
-Note that
-\fBclearok\fP,
-\fBleaveok\fP,
-\fBscrollok\fP,
-\fBidcok\fP, and
-\fBsetscrreg\fP may be macros.
-.PP
-The \fBimmedok\fP routine is useful for windows that are used as terminal
-emulators.
+.SH HISTORY
+.I \%ncurses
+formerly treated \fBnl\fP(3X) and \fBnonl\fP(3X) as both input
+.I and
+output options,
+but no longer;
+see \fB\%curs_inopts\fP(3X).
.SH SEE ALSO
-.na
-\fBcurses\fP(3X),
-\fBcurs_addch\fP(3X),
-\fBcurs_clear\fP(3X),
-\fBcurs_initscr\fP(3X),
-\fBcurs_scroll\fP(3X),
-\fBcurs_refresh\fP(3X),
-\fBcurs_variables\fP(3X).
+\fB\%curses\fP(3X),
+\fB\%curs_addch\fP(3X),
+\fB\%curs_clear\fP(3X),
+\fB\%curs_initscr\fP(3X),
+\fB\%curs_refresh\fP(3X),
+\fB\%curs_scroll\fP(3X),
+\fB\%curs_variables\fP(3X)
projects / ncurses.git / blobdiff