.\"***************************************************************************
-.\" Copyright (c) 1998-2002,2003 Free Software Foundation, Inc. *
+.\" Copyright (c) 1998-2006,2010 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. *
.\"***************************************************************************
.\"
-.\" Author: Thomas E. Dickey 1997,1999,2000
+.\" Author: Thomas E. Dickey 1997,1999,2000,2005
.\"
-.\" $Id: default_colors.3x,v 1.17 2003/10/25 20:41:08 tom Exp $
+.\" $Id: default_colors.3x,v 1.21 2010/07/31 16:10:55 tom Exp $
.TH default_colors 3X ""
.SH NAME
\fBuse_default_colors\fR,
\fBassume_default_colors\fR \- use terminal's default colors
.SH SYNOPSIS
\fB#include <curses.h>\fP
-
+.sp
\fBint use_default_colors(void);\fP
.br
\fBint assume_default_colors(int fg, int bg);\fP
The first function,
.I use_default_colors()
tells the curses library to assign terminal default
-foreground/background colors to color number -1. So init_pair(x,COLOR_RED,-1)
-will initialize pair x as red on default background and init_pair(x,-1,COLOR_BLUE) will
+foreground/background colors to color number \-1. So init_pair(x,COLOR_RED,\-1)
+will initialize pair x as red on default background and init_pair(x,\-1,COLOR_BLUE) will
initialize pair x as default foreground on blue.
.PP
The other,
.I assume_default_colors()
is a refinement which tells which colors to paint for color pair 0.
-This function recognizes a special color number -1,
+This function recognizes a special color number \-1,
which denotes the default terminal color.
.PP
The following are equivalent:
.br
.I use_default_colors();
.br
-.I assume_default_colors(-1,-1);
+.I assume_default_colors(\-1,\-1);
.RE
.PP
These are ncurses extensions.
For other curses implementations, color
-number -1 does not mean anything, just as for ncurses before a
+number \-1 does not mean anything, just as for ncurses before a
successful call of \fIuse_default_colors()\fP or \fIassume_default_colors()\fP.
.PP
Other curses implementations do not allow an application to modify color pair 0.
If the \fIinitialize_pair\fP capability is found, this causes an
error as well.
.SH NOTES
-Associated with this extension, the \fBinit_pair\fR(3X) function accepts
-negative arguments to specify default foreground or background
-colors.
+Associated with this extension, the \fBinit_pair\fR function accepts
+negative arguments to specify default foreground or background colors.
+.PP
+The \fIuse_default_colors()\fP function was added to support \fIded\fP.
+This is a full-screen application which uses curses to manage only part
+of the screen. The bottom portion of the screen, which is of adjustable
+size, is left uncolored to display the results from shell commands.
+The top portion of the screen colors filenames using a scheme like the
+"color ls" programs.
+Attempting to manage the background color of the screen for this application
+would give unsatisfactory results for a variety of reasons.
+This extension was devised after
+noting that color xterm (and similar programs) provides a background color
+which does not necessarily correspond to any of the ANSI colors.
+While a special terminfo entry could be constructed using nine colors,
+there was no mechanism provided within curses to account for the related
+\fIorig_pair\fP and \fIback_color_erase\fP capabilities.
+.PP
+The \fIassume_default_colors()\fP function was added to solve
+a different problem: support for applications which would use
+environment variables and other configuration to bypass curses'
+notion of the terminal's default colors, setting specific values.
.SH PORTABILITY
These routines are specific to ncurses. They were not supported on
Version 7, BSD or System V implementations. It is recommended that
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