.\"***************************************************************************
-.\" Copyright 2020,2021 Thomas E. Dickey *
+.\" Copyright 2020-2023,2024 Thomas E. Dickey *
.\" Copyright 1998-2015,2016 Free Software Foundation, Inc. *
.\" *
.\" Permission is hereby granted, free of charge, to any person obtaining a *
.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: curs_window.3x,v 1.24 2021/12/25 17:39:16 tom Exp $
-.TH curs_window 3X ""
-.de bP
-.ie n .IP \(bu 4
-.el .IP \(bu 2
-..
-.na
-.hy 0
+.\" $Id: curs_window.3x,v 1.50 2024/05/25 20:43:47 tom Exp $
+.TH curs_window 3X 2024-05-25 "ncurses @NCURSES_MAJOR@.@NCURSES_MINOR@" "Library calls"
.SH NAME
-\fBnewwin\fP,
-\fBdelwin\fP,
-\fBmvwin\fP,
-\fBsubwin\fP,
-\fBderwin\fP,
-\fBmvderwin\fP,
-\fBdupwin\fP,
-\fBwsyncup\fP,
-\fBsyncok\fP,
-\fBwcursyncup\fP,
-\fBwsyncdown\fP \- create \fBcurses\fP windows
-.ad
-.hy
+\fB\%newwin\fP,
+\fB\%delwin\fP,
+\fB\%mvwin\fP,
+\fB\%subwin\fP,
+\fB\%derwin\fP,
+\fB\%mvderwin\fP,
+\fB\%dupwin\fP,
+\fB\%wsyncup\fP,
+\fB\%syncok\fP,
+\fB\%wcursyncup\fP,
+\fB\%wsyncdown\fP \-
+create and manipulate \fIcurses\fR windows
.SH SYNOPSIS
-\fB#include <curses.h>\fP
-.sp
-\fBWINDOW *newwin(\fP
- \fBint \fP\fInlines\fP\fB, int \fP\fIncols\fP\fB,\fP
- \fBint \fP\fIbegin_y\fP\fB, int \fP\fIbegin_x\fP\fB);\fP
-.br
-\fBint delwin(WINDOW *\fP\fIwin\fP\fB);\fP
-.br
-\fBint mvwin(WINDOW *\fP\fIwin\fP\fB, int \fP\fIy\fP\fB, int \fP\fIx\fP\fB);\fP
-.br
-\fBWINDOW *subwin(WINDOW *\fP\fIorig\fP\fB,\fP
- \fBint \fP\fInlines\fP\fB, int \fP\fIncols\fP\fB,\fP
- \fBint \fP\fIbegin_y\fP\fB, int \fP\fIbegin_x\fP\fB);\fP
-.br
-\fBWINDOW *derwin(WINDOW *\fP\fIorig\fP\fB,\fP
- \fBint \fP\fInlines\fP\fB, int \fP\fIncols\fP\fB,\fP
- \fBint \fP\fIbegin_y\fP\fB, int \fP\fIbegin_x\fP\fB);\fP
-.br
-\fBint mvderwin(WINDOW *\fP\fIwin\fP\fB, int \fP\fIpar_y\fP\fB, int \fP\fIpar_x\fP\fB);\fP
-.br
-\fBWINDOW *dupwin(WINDOW *\fP\fIwin\fP\fB);\fP
-.br
-\fBvoid wsyncup(WINDOW *\fP\fIwin\fP\fB);\fP
-.br
-\fBint syncok(WINDOW *\fP\fIwin\fP\fB, bool \fP\fIbf\fP\fB);\fP
-.br
-\fBvoid wcursyncup(WINDOW *\fP\fIwin\fP\fB);\fP
-.br
-\fBvoid wsyncdown(WINDOW *\fP\fIwin\fP\fB);\fP
-.br
+.nf
+\fB#include <curses.h>
+.PP
+\fBWINDOW *newwin(
+ \fBint \fInlines\fB, int \fIncols\fB,\fR
+ \fBint \fIbegin_y\fB, int \fIbegin_x\fB);\fR
+\fBint delwin(WINDOW *\fIwin\fB);\fR
+\fBint mvwin(WINDOW *\fIwin\fB, int \fIy\fB, int \fIx\fB);\fR
+\fBWINDOW *subwin(WINDOW *\fIorig\fB,\fR
+ \fBint \fInlines\fB, int \fIncols\fB,\fR
+ \fBint \fIbegin_y\fB, int \fIbegin_x\fB);\fR
+\fBWINDOW *derwin(WINDOW *\fIorig\fB,\fR
+ \fBint \fInlines\fB, int \fIncols\fB,\fR
+ \fBint \fIbegin_y\fB, int \fIbegin_x\fB);\fR
+\fBint mvderwin(WINDOW *\fIwin\fB, int \fIpar_y\fB, int \fIpar_x\fB);\fR
+\fBWINDOW *dupwin(WINDOW *\fIwin\fB);\fR
+\fBvoid wsyncup(WINDOW *\fIwin\fB);\fR
+\fBint syncok(WINDOW *\fIwin\fB, bool \fIbf\fB);\fR
+\fBvoid wcursyncup(WINDOW *\fIwin\fB);\fR
+\fBvoid wsyncdown(WINDOW *\fIwin\fB);\fR
+.fi
.SH DESCRIPTION
.SS newwin
Calling \fBnewwin\fP creates and returns a pointer to a new window with the
all of the window modes are initialized to the default values.
These functions set window modes after a window is created:
.RS
-.na
.PP
-idcok,
-idlok,
-immedok,
-keypad,
-leaveok,
-nodelay,
-scrollok,
-setscrreg,
-syncok,
-wbkgdset,
-wbkgrndset, and
-wtimeout
+\fB\%idcok\fP
+\fB\%idlok\fP
+\fB\%immedok\fP
+\fB\%keypad\fP
+\fB\%leaveok\fP
+\fB\%nodelay\fP
+\fB\%scrollok\fP
+\fB\%setscrreg\fP
+\fB\%syncok\fP
+\fB\%wbkgdset\fP
+\fB\%wbkgrndset\fP and
+\fB\%wtimeout\fP.
.RE
-.ad
.SS delwin
-.PP
Calling \fBdelwin\fP deletes the named window, freeing all memory
associated with it (it does not actually erase the window's screen
image).
Subwindows must be deleted before the main window can be deleted.
.SS mvwin
-.PP
Calling \fBmvwin\fP moves the window so that the upper left-hand
corner is at position (\fIx\fP, \fIy\fP).
If the move would cause the window to be off the screen,
it is an error and the window is not moved.
Moving subwindows is allowed, but should be avoided.
.SS subwin
-.PP
Calling \fBsubwin\fP creates and returns a pointer to a new window
with the given number of lines, \fInlines\fP, and columns, \fIncols\fP.
The window is at position (\fIbegin\fR_\fIy\fP,
\fIbegin\fR_\fIx\fP) on the screen.
The subwindow shares memory with the window \fIorig\fP,
+its \fIancestor\fP,
so that changes made to one window
will affect both windows.
When using this routine, it is necessary to call
\fBtouchwin\fP or \fBtouchline\fP on \fIorig\fP before calling
\fBwrefresh\fP on the subwindow.
.SS derwin
-.PP
Calling \fBderwin\fP is the same as calling \fBsubwin,\fP except that
\fIbegin\fR_\fIy\fP and \fIbegin\fR_\fIx\fP are relative to the origin
of the window \fIorig\fP rather than the screen.
There is no difference between the subwindows and the derived windows.
-.PP
+.SS mvderwin
Calling \fBmvderwin\fP moves a derived window (or subwindow)
inside its parent window.
The screen-relative parameters of the window are not changed.
parts of the parent window at the same physical position on the
screen.
.SS dupwin
-.PP
Calling \fBdupwin\fP creates an exact duplicate of the window \fIwin\fP.
.SS wsyncup
-.PP
Calling \fBwsyncup\fP touches all locations in ancestors of \fIwin\fP that are
changed in \fIwin\fP.
If \fBsyncok\fP is called with second argument
\fBTRUE\fP then \fBwsyncup\fP is called automatically whenever there is a
change in the window.
.SS wsyncdown
-.PP
The \fBwsyncdown\fP routine touches each location in \fIwin\fP that has been
touched in any of its ancestor windows.
This routine is called by
\fBwrefresh\fP, so it should almost never be necessary to call it manually.
.SS wcursyncup
-.PP
The routine \fBwcursyncup\fP updates the current cursor position of all the
ancestors of the window to reflect the current cursor position of the
window.
In this implementation
.TP 5
\fBdelwin\fP
-returns an error if the window pointer is null, or
+returns
+.B ERR
+if the window pointer is null, or
if the window is the parent of another window.
.TP 5
\fBderwin\fP
-returns an error if the parent window pointer is null, or
+returns
+.B ERR
+if the parent window pointer is null, or
if any of its ordinates or dimensions is negative, or
if the resulting window does not fit inside the parent window.
.TP 5
\fBdupwin\fP
-returns an error if the window pointer is null.
+returns
+.B ERR
+if the window pointer is null.
.IP
This implementation also maintains a list of windows,
and checks that the pointer passed to \fBdelwin\fP is one that
it created, returning an error if it was not..
.TP 5
\fBmvderwin\fP
-returns an error
+returns
+.B ERR
if the window pointer is null, or
if some part of the window would be placed off-screen.
.TP 5
\fBmvwin\fP
-returns an error
+returns
+.B ERR
if the window pointer is null, or
if the window is really a pad, or
if some part of the window would be placed off-screen.
if either the number of lines or columns is negative.
.TP 5
\fBsyncok\fP
-returns an error
+returns
+.B ERR
if the window pointer is null.
.TP 5
\fBsubwin\fP
-returns an error if the parent window pointer is null, or
+returns
+.B ERR
+if the parent window pointer is null, or
if any of its ordinates or dimensions is negative, or
if the resulting window does not fit inside the parent window.
.PP
degrade performance.
.PP
Note that \fBsyncok\fP may be a macro.
-.SH BUGS
-The subwindow functions (\fBsubwin\fP, \fBderwin\fP, \fBmvderwin\fP,
-\fBwsyncup\fP, \fBwsyncdown\fP, \fBwcursyncup\fP, \fBsyncok\fP) are flaky,
-incompletely implemented, and not well tested.
-.PP
-The System V curses documentation is very unclear about what \fBwsyncup\fP
-and \fBwsyncdown\fP actually do.
-It seems to imply that they are only
-supposed to touch exactly those lines that are affected by ancestor changes.
-The language here, and the behavior of the \fBcurses\fP implementation,
-is patterned on the XPG4 curses standard.
-The weaker XPG4 spec may result in slower updates.
.SH PORTABILITY
-The XSI Curses standard, Issue 4 describes these functions.
+X/Open Curses, Issue 4 describes these functions.
+.PP
+Regarding
+.IR \%delwin ","
+X/Open Curses states that
+.RS
+.PP
+[t]he application must delete subwindows before deleting the main
+window.
+.RE
+.PP
+If
+.I \%delwin
+is asked to delete a parent window,
+it can succeed only if the
+.I curses
+library keeps a list of its subwindows.
+SVr4
+.I curses
+kept a count of the number of subwindows rather than a list.
+It simply returned
+.B ERR
+when asked to delete a subwindow.
+Solaris X/Open
+.I curses
+.RI ( \%xcurses )
+does not make even that check,
+and will delete a parent window that still has subwindows.
+.I \%PDCurses
+also behaves this way.
+.PP
+.I \%ncurses
+4.0 (1996) and later maintains a list of windows for each screen
+to ensure that a window has no subwindows before allowing its deletion.
+NetBSD
+.I curses
+has followed suit since 2003.
+.PP
+SVr4
+.I curses
+documentation is unclear about what
+.I \%wsyncup
+and
+.I \%wsyncdown
+actually do.
+It seems to imply that they are supposed to touch only those lines that
+are affected by changes to a window's ancestors.
+The description and behavior of these functions in
+.I \%ncurses
+is patterned on the X/Open Curses standard;
+this approach may result in slower updates.
.SH SEE ALSO
-\fBcurses\fP(3X),
-\fBcurs_refresh\fP(3X),
-\fBcurs_touch\fP(3X),
-\fBcurs_variables\fP(3X)
+\fB\%curses\fP(3X),
+\fB\%curs_initscr\fP(3X),
+\fB\%curs_refresh\fP(3X),
+\fB\%curs_touch\fP(3X),
+\fB\%curs_variables\fP(3X)