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- * Author: Thomas E. Dickey 1997,1999,2000
- * @Id: default_colors.3x,v 1.17 2003/10/25 20:41:08 tom Exp @
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-<H1>default_colors 3x</H1>
-<HR>
+<H1 class="no-header">default_colors 3x</H1>
<PRE>
-<!-- Manpage converted by man2html 3.0.1 -->
-<STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG> <STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG>
+<STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG> <STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG>
-</PRE>
-<H2>NAME</H2><PRE>
- <STRONG>use_default_colors</STRONG>, <STRONG>assume_default_colors</STRONG> - use terminal's
- default colors
+</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
+ <STRONG>use_default_colors</STRONG>, <STRONG>assume_default_colors</STRONG> - use terminal's default col-
+ ors
-</PRE>
-<H2>SYNOPSIS</H2><PRE>
+</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
<STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
<STRONG>int</STRONG> <STRONG>use_default_colors(void);</STRONG>
<STRONG>int</STRONG> <STRONG>assume_default_colors(int</STRONG> <STRONG>fg,</STRONG> <STRONG>int</STRONG> <STRONG>bg);</STRONG>
-</PRE>
-<H2>DESCRIPTION</H2><PRE>
- The <EM>use</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>colors()</EM> and <EM>assume</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>colors()</EM> func-
- tions are extensions to the curses library. They are used
- with terminals that support ISO 6429 color, or equivalent.
- These terminals allow the application to reset color to an
- unspecified default value (e.g., with SGR 39 or SGR 49).
-
- Applications that paint a colored background over the
- whole screen do not take advantage of SGR 39 and SGR 49.
- Some applications are designed to work with the default
- background, using colors only for text. For example,
- there are several implementations of the <STRONG>ls</STRONG> program which
- use colors to denote different file types or permissions.
- These "color ls" programs do not necessarily modify the
- background color, typically using only the <EM>setaf</EM> terminfo
- capability to set the foreground color. Full-screen
- applications that use default colors can achieve similar
- visual effects.
-
- The first function, <EM>use</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>colors()</EM> 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 initialize pair x as
- default foreground on blue.
-
- The other, <EM>assume</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>colors()</EM> is a refinement which
- tells which colors to paint for color pair 0. This func-
- tion recognizes a special color number -1, which denotes
- the default terminal color.
+</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
+ The <STRONG>use_default_colors</STRONG> and <STRONG>assume_default_colors</STRONG> functions are exten-
+ sions to the curses library. They are used with terminals that support
+ ISO 6429 color, or equivalent. These terminals allow the application
+ to reset color to an unspecified default value (e.g., with SGR 39 or
+ SGR 49).
+
+ Applications that paint a colored background over the whole screen do
+ not take advantage of SGR 39 and SGR 49. Some applications are
+ designed to work with the default background, using colors only for
+ text. For example, there are several implementations of the <STRONG>ls</STRONG> program
+ which use colors to denote different file types or permissions. These
+ "color ls" programs do not necessarily modify the background color,
+ typically using only the <STRONG>setaf</STRONG> terminfo capability to set the fore-
+ ground color. Full-screen applications that use default colors can
+ achieve similar visual effects.
+
+ The first function, <STRONG>use_default_colors</STRONG> 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 initialize pair
+ x as default foreground on blue.
+
+ The other, <STRONG>assume_default_colors</STRONG> is a refinement which tells which col-
+ ors to paint for color pair 0. This function recognizes a special
+ color number -1, which denotes the default terminal color.
The following are equivalent:
<EM>use</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>colors();</EM>
<EM>assume</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>colors(-1,-1);</EM>
- These are ncurses extensions. For other curses implemen-
- tations, color number -1 does not mean anything, just as
- for ncurses before a successful call of <EM>use</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>col-</EM>
- <EM>ors()</EM> or <EM>assume</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>colors()</EM>.
-
- Other curses implementations do not allow an application
- to modify color pair 0. They assume that the background
- is COLOR_BLACK, but do not ensure that the color pair 0 is
- painted to match the assumption. If your application does
- not use either <EM>use</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>colors()</EM> or <EM>assume</EM><STRONG>_</STRONG><EM>default</EM><STRONG>_</STRONG><EM>col-</EM>
- <EM>ors()</EM> ncurses will paint a white foreground (text) with
+ These are ncurses extensions. For other curses implementations, color
+ number -1 does not mean anything, just as for ncurses before a success-
+ ful call of <STRONG>use_default_colors</STRONG> or <STRONG>assume_default_colors</STRONG>.
+
+ Other curses implementations do not allow an application to modify
+ color pair 0. They assume that the background is COLOR_BLACK, but do
+ not ensure that the color pair 0 is painted to match the assumption.
+ If your application does not use either <STRONG>use_default_colors</STRONG> or
+ <STRONG>assume_default_colors</STRONG> ncurses will paint a white foreground (text) with
black background for color pair 0.
-</PRE>
-<H2>RETURN VALUE</H2><PRE>
- These functions return the integer <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG>
- on success. They will fail if either the terminal does
- not support the <EM>orig</EM><STRONG>_</STRONG><EM>pair</EM> or <EM>orig</EM><STRONG>_</STRONG><EM>colors</EM> capability. If
- the <EM>initialize</EM><STRONG>_</STRONG><EM>pair</EM> capability is found, this causes an
- error as well.
+</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
+ These functions return the integer <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> on success.
+ They will fail if either the terminal does not support the <STRONG>orig_pair</STRONG> or
+ <STRONG>orig_colors</STRONG> capability. If the <STRONG>initialize_pair</STRONG> capability is not
+ found, this causes an error as well.
-</PRE>
-<H2>NOTES</H2><PRE>
- Associated with this extension, the <STRONG><A HREF="init_pair.3x.html">init_pair(3x)</A></STRONG> function
- accepts negative arguments to specify default foreground
- or background colors.
+</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
+ Associated with this extension, the <STRONG>init_pair</STRONG> function accepts negative
+ arguments to specify default foreground or background colors.
+ The <STRONG>use_default_colors</STRONG> function was added to support <EM>ded</EM>. 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 necessar-
+ ily 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 <STRONG>orig_pair</STRONG> and
+ <STRONG>back_color_erase</STRONG> capabilities.
-</PRE>
-<H2>PORTABILITY</H2><PRE>
- These routines are specific to ncurses. They were not
- supported on Version 7, BSD or System V implementations.
- It is recommended that any code depending on them be con-
- ditioned using NCURSES_VERSION.
+ The <STRONG>assume_default_colors</STRONG> function was added to solve a different prob-
+ lem: support for applications which would use environment variables and
+ other configuration to bypass curses' notion of the terminal's default
+ colors, setting specific values.
-</PRE>
-<H2>SEE ALSO</H2><PRE>
- <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>, <STRONG><A HREF="ded.1.html">ded(1)</A></STRONG>.
+</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
+ These routines are specific to ncurses. They were not supported on
+ Version 7, BSD or System V implementations. It is recommended that any
+ code depending on them be conditioned using NCURSES_VERSION.
-</PRE>
-<H2>AUTHOR</H2><PRE>
- Thomas Dickey (from an analysis of the requirements for
- color xterm for XFree86 3.1.2C, February 1996).
+</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
+ <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>, <STRONG>ded(1)</STRONG>.
+
+
+</PRE><H2><a name="h2-AUTHOR">AUTHOR</a></H2><PRE>
+ Thomas Dickey (from an analysis of the requirements for color xterm for
+ XFree86 3.1.2C, February 1996).
- <STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG>
+
<STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG>
</PRE>
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+<ul>
+<li><a href="#h2-NAME">NAME</a></li>
+<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
+<li><a href="#h2-DESCRIPTION">DESCRIPTION</a></li>
+<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
+<li><a href="#h2-NOTES">NOTES</a></li>
+<li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
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