.\"	$NetBSD: panel_above.3,v 1.8 2015/11/01 14:47:54 wiz Exp $
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.\" Copyright (c) 2015 Valery Ushakov
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.Dd October 28, 2015
.Dt PANEL_ABOVE 3
.Os
.Sh NAME
.Nm top_panel ,
.Nm bottom_panel ,
.Nm panel_above ,
.Nm panel_below
.Nd z-order of panels
.Sh LIBRARY
.Lb libpanel
.Sh SYNOPSIS
.In panel.h
.\"
.Ft int
.Fn top_panel "PANEL *p"
.\"
.Ft int
.Fn bottom_panel "PANEL *p"
.\"
.Ft PANEL *
.Fn panel_above "PANEL *p"
.\"
.Ft PANEL *
.Fn panel_below "PANEL *p"
.\"
.Sh DESCRIPTION
Newly created panels are placed at the top of the deck.
The z-order of a visible panel can be changed with the functions
.Fn top_panel
and
.Fn bottom_panel
that move it to the top and bottom of the deck respectively.
.Pp
For a visible panel its neighbors in the deck can be obtained with
.Fn panel_above
and
.Fn panel_below .
The bottom and top panels can be obtained by passing a
.Dv NULL
argument to
.Fn panel_above
and
.Fn panel_below ,
respectively.
.Sh IMPLEMENTATION NOTES
The
.Fn top_panel
function will return an error if the panel is currently hidden.
Use
.Xr show_panel 3
to make a hidden panel visible again and put it at the top of the deck.
This is the behaviour specified by the original
.At V
panel library.
.Pp
In the ncurses implementation of the panel library
.Fn show_panel
and
.Fn top_panel
are identical and handle both visible and hidden panels.
This may be a source of bugs in programs tested only against ncurses.
.Sh RETURN VALUES
Functions returning pointers will return
.Dv NULL
if an error is detected.
The functions that return an int will return one of the following
values:
.Pp
.Bl -tag -width ".Dv ERR" -compact
.It Dv OK
The function completed successfully.
.It Dv ERR
An error occurred in the function.
.El
.Sh SEE ALSO
.Xr panel 3