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<H1 class="no-header">curs_color 3x</H1>
<PRE>
<STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG> <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>
</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
<STRONG>start_color</STRONG>, <STRONG>has_colors</STRONG>, <STRONG>can_change_color</STRONG>, <STRONG>init_pair</STRONG>, <STRONG>init_color</STRONG>,
<STRONG>init_extended_pair</STRONG>, <STRONG>init_extended_color</STRONG>, <STRONG>color_content</STRONG>, <STRONG>pair_content</STRONG>,
<STRONG>extended_color_content</STRONG>, <STRONG>extended_pair_content</STRONG>, <STRONG>reset_color_pairs</STRONG>,
<STRONG>COLOR_PAIR</STRONG>, <STRONG>PAIR_NUMBER</STRONG> - <STRONG>curses</STRONG> color manipulation routines
</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
<STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
<STRONG>int</STRONG> <STRONG>start_color(void);</STRONG>
<STRONG>bool</STRONG> <STRONG>has_colors(void);</STRONG>
<STRONG>bool</STRONG> <STRONG>can_change_color(void);</STRONG>
<STRONG>int</STRONG> <STRONG>init_pair(short</STRONG> <STRONG>pair,</STRONG> <STRONG>short</STRONG> <STRONG>f,</STRONG> <STRONG>short</STRONG> <STRONG>b);</STRONG>
<STRONG>int</STRONG> <STRONG>init_color(short</STRONG> <STRONG>color,</STRONG> <STRONG>short</STRONG> <STRONG>r,</STRONG> <STRONG>short</STRONG> <STRONG>g,</STRONG> <STRONG>short</STRONG> <STRONG>b);</STRONG>
/* extensions */
<STRONG>int</STRONG> <STRONG>init_extended_pair(int</STRONG> <STRONG>pair,</STRONG> <STRONG>int</STRONG> <STRONG>f,</STRONG> <STRONG>int</STRONG> <STRONG>b);</STRONG>
<STRONG>int</STRONG> <STRONG>init_extended_color(int</STRONG> <STRONG>color,</STRONG> <STRONG>int</STRONG> <STRONG>r,</STRONG> <STRONG>int</STRONG> <STRONG>g,</STRONG> <STRONG>int</STRONG> <STRONG>b);</STRONG>
<STRONG>int</STRONG> <STRONG>color_content(short</STRONG> <STRONG>color,</STRONG> <STRONG>short</STRONG> <STRONG>*r,</STRONG> <STRONG>short</STRONG> <STRONG>*g,</STRONG> <STRONG>short</STRONG> <STRONG>*b);</STRONG>
<STRONG>int</STRONG> <STRONG>pair_content(short</STRONG> <STRONG>pair,</STRONG> <STRONG>short</STRONG> <STRONG>*f,</STRONG> <STRONG>short</STRONG> <STRONG>*b);</STRONG>
/* extensions */
<STRONG>int</STRONG> <STRONG>extended_color_content(int</STRONG> <STRONG>color,</STRONG> <STRONG>int</STRONG> <STRONG>*r,</STRONG> <STRONG>int</STRONG> <STRONG>*g,</STRONG> <STRONG>int</STRONG> <STRONG>*b);</STRONG>
<STRONG>int</STRONG> <STRONG>extended_pair_content(int</STRONG> <STRONG>pair,</STRONG> <STRONG>int</STRONG> <STRONG>*f,</STRONG> <STRONG>int</STRONG> <STRONG>*b);</STRONG>
/* extensions */
<STRONG>void</STRONG> <STRONG>reset_color_pairs(void);</STRONG>
<STRONG>int</STRONG> <STRONG>COLOR_PAIR(int</STRONG> <STRONG>n);</STRONG>
<STRONG>PAIR_NUMBER(</STRONG><EM>attrs</EM><STRONG>);</STRONG>
</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
</PRE><H3><a name="h3-Overview">Overview</a></H3><PRE>
<STRONG>curses</STRONG> supports color attributes on terminals with that capability. To
use these routines <STRONG>start_color</STRONG> must be called, usually right after
<STRONG>initscr</STRONG>. Colors are always used in pairs (referred to as color-pairs).
A color-pair consists of a foreground color (for characters) and a
background color (for the blank field on which the characters are dis-
played). A programmer initializes a color-pair with the routine
<STRONG>init_pair</STRONG>. After it has been initialized, <STRONG>COLOR_PAIR</STRONG>(<EM>n</EM>) can be used to
convert the pair to a video attribute.
If a terminal is capable of redefining colors, the programmer can use
the routine <STRONG>init_color</STRONG> to change the definition of a color. The rou-
tines <STRONG>has_colors</STRONG> and <STRONG>can_change_color</STRONG> return <STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG>, depending
on whether the terminal has color capabilities and whether the program-
mer can change the colors. The routine <STRONG>color_content</STRONG> allows a program-
mer to extract the amounts of red, green, and blue components in an
initialized color. The routine <STRONG>pair_content</STRONG> allows a programmer to
find out how a given color-pair is currently defined.
</PRE><H3><a name="h3-Color-Rendering">Color Rendering</a></H3><PRE>
The <STRONG>curses</STRONG> library combines these inputs to produce the actual fore-
ground and background colors shown on the screen:
<STRONG>o</STRONG> per-character video attributes (e.g., via <STRONG>waddch</STRONG>),
<STRONG>o</STRONG> the window attribute (e.g., by <STRONG>wattrset</STRONG>), and
<STRONG>o</STRONG> the background character (e.g., <STRONG>wbkgdset</STRONG>).
Per-character and window attributes are usually set by a parameter con-
taining video attributes including a color pair value. Some functions
such as <STRONG>wattr_set</STRONG> use a separate parameter which is the color pair num-
ber.
The background character is a special case: it includes a character
value, just as if it were passed to <STRONG>waddch</STRONG>.
The <STRONG>curses</STRONG> library does the actual work of combining these color pairs
in an internal function called from <STRONG>waddch</STRONG>:
<STRONG>o</STRONG> If the parameter passed to <STRONG>waddch</STRONG> is <EM>blank</EM>, and it uses the special
color pair 0,
<STRONG>o</STRONG> <STRONG>curses</STRONG> next checks the window attribute.
<STRONG>o</STRONG> If the window attribute does not use color pair 0, <STRONG>curses</STRONG> uses
the color pair from the window attribute.
<STRONG>o</STRONG> Otherwise, <STRONG>curses</STRONG> uses the background character.
<STRONG>o</STRONG> If the parameter passed to <STRONG>waddch</STRONG> is <EM>not</EM> <EM>blank</EM>, or it does not use
the special color pair 0, <STRONG>curses</STRONG> prefers the color pair from the
parameter, if it is nonzero. Otherwise, it tries the window at-
tribute next, and finally the background character.
Some <STRONG>curses</STRONG> functions such as <STRONG>wprintw</STRONG> call <STRONG>waddch</STRONG>. Those do not com-
bine its parameter with a color pair. Consequently those calls use on-
ly the window attribute or the background character.
</PRE><H2><a name="h2-CONSTANTS">CONSTANTS</a></H2><PRE>
In <STRONG><curses.h></STRONG> the following macros are defined. These are the standard
colors (ISO-6429). <STRONG>curses</STRONG> also assumes that <STRONG>COLOR_BLACK</STRONG> is the default
background color for all terminals.
<STRONG>COLOR_BLACK</STRONG>
<STRONG>COLOR_RED</STRONG>
<STRONG>COLOR_GREEN</STRONG>
<STRONG>COLOR_YELLOW</STRONG>
<STRONG>COLOR_BLUE</STRONG>
<STRONG>COLOR_MAGENTA</STRONG>
<STRONG>COLOR_CYAN</STRONG>
<STRONG>COLOR_WHITE</STRONG>
Some terminals support more than the eight (8) "ANSI" colors. There
are no standard names for those additional colors.
</PRE><H2><a name="h2-VARIABLES">VARIABLES</a></H2><PRE>
</PRE><H3><a name="h3-COLORS">COLORS</a></H3><PRE>
is initialized by <STRONG>start_color</STRONG> to the maximum number of colors the ter-
minal can support.
</PRE><H3><a name="h3-COLOR_PAIRS">COLOR_PAIRS</a></H3><PRE>
is initialized by <STRONG>start_color</STRONG> to the maximum number of color pairs the
terminal can support.
</PRE><H2><a name="h2-FUNCTIONS">FUNCTIONS</a></H2><PRE>
</PRE><H3><a name="h3-start_color">start_color</a></H3><PRE>
The <STRONG>start_color</STRONG> routine requires no arguments. It must be called if
the programmer wants to use colors, and before any other color manipu-
lation routine is called. It is good practice to call this routine
right after <STRONG>initscr</STRONG>. <STRONG>start_color</STRONG> does this:
<STRONG>o</STRONG> It initializes two global variables, <STRONG>COLORS</STRONG> and <STRONG>COLOR_PAIRS</STRONG> (re-
spectively defining the maximum number of colors and color-pairs
the terminal can support).
<STRONG>o</STRONG> It initializes the special color pair <STRONG>0</STRONG> to the default foreground
and background colors. No other color pairs are initialized.
<STRONG>o</STRONG> It restores the colors on the terminal to the values they had when
the terminal was just turned on.
<STRONG>o</STRONG> If the terminal supports the <STRONG>initc</STRONG> (<STRONG>initialize_color</STRONG>) capability,
<STRONG>start_color</STRONG> initializes its internal table representing the red,
green, and blue components of the color palette.
The components depend on whether the terminal uses CGA (aka "ANSI")
or HLS (i.e., the <STRONG>hls</STRONG> (<STRONG>hue_lightness_saturation</STRONG>) capability is
set). The table is initialized first for eight basic colors
(black, red, green, yellow, blue, magenta, cyan, and white), using
weights that depend upon the CGA/HLS choice. For "ANSI" colors the
weights are <STRONG>680</STRONG> or <STRONG>0</STRONG> depending on whether the corresponding red,
green, or blue component is used or not. That permits using <STRONG>1000</STRONG>
to represent bold/bright colors. After the initial eight colors
(if the terminal supports more than eight colors) the components
are initialized using the same pattern, but with weights of <STRONG>1000</STRONG>.
SVr4 uses a similar scheme, but uses <STRONG>1000</STRONG> for the components of the
initial eight colors.
<STRONG>start_color</STRONG> does not attempt to set the terminal's color palette to
match its built-in table. An application may use <STRONG>init_color</STRONG> to al-
ter the internal table along with the terminal's color.
These limits apply to color values and color pairs. Values outside
these limits are not legal, and may result in a runtime error:
<STRONG>o</STRONG> <STRONG>COLORS</STRONG> corresponds to the terminal database's <STRONG>max_colors</STRONG> capabili-
ty, (see <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>).
<STRONG>o</STRONG> color values are expected to be in the range <STRONG>0</STRONG> to <STRONG>COLORS-1</STRONG>, inclu-
sive (including <STRONG>0</STRONG> and <STRONG>COLORS-1</STRONG>).
<STRONG>o</STRONG> a special color value <STRONG>-1</STRONG> is used in certain extended functions to
denote the <EM>default</EM> <EM>color</EM> (see <STRONG><A HREF="default_colors.3x.html">use_default_colors(3x)</A></STRONG>).
<STRONG>o</STRONG> <STRONG>COLOR_PAIRS</STRONG> corresponds to the terminal database's <STRONG>max_pairs</STRONG> capa-
bility, (see <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>).
<STRONG>o</STRONG> legal color pair values are in the range <STRONG>1</STRONG> to <STRONG>COLOR_PAIRS-1</STRONG>, inclu-
sive.
<STRONG>o</STRONG> color pair <STRONG>0</STRONG> is special; it denotes "no color".
Color pair <STRONG>0</STRONG> is assumed to be white on black, but is actually what-
ever the terminal implements before color is initialized. It can-
not be modified by the application.
</PRE><H3><a name="h3-has_colors">has_colors</a></H3><PRE>
The <STRONG>has_colors</STRONG> routine requires no arguments. It returns <STRONG>TRUE</STRONG> if the
terminal can manipulate colors; otherwise, it returns <STRONG>FALSE</STRONG>. This rou-
tine facilitates writing terminal-independent programs. For example, a
programmer can use it to decide whether to use color or some other
video attribute.
</PRE><H3><a name="h3-can_change_color">can_change_color</a></H3><PRE>
The <STRONG>can_change_color</STRONG> routine requires no arguments. It returns <STRONG>TRUE</STRONG> if
the terminal supports colors and can change their definitions; other,
it returns <STRONG>FALSE</STRONG>. This routine facilitates writing terminal-indepen-
dent programs.
</PRE><H3><a name="h3-init_pair">init_pair</a></H3><PRE>
The <STRONG>init_pair</STRONG> routine changes the definition of a color-pair. It takes
three arguments: the number of the color-pair to be changed, the fore-
ground color number, and the background color number. For portable ap-
plications:
<STRONG>o</STRONG> The first argument must be a legal color pair value. If default
colors are used (see <STRONG><A HREF="default_colors.3x.html">use_default_colors(3x)</A></STRONG>) the upper limit is ad-
justed to allow for extra pairs which use a default color in fore-
ground and/or background.
<STRONG>o</STRONG> The second and third arguments must be legal color values.
If the color-pair was previously initialized, the screen is refreshed
and all occurrences of that color-pair are changed to the new defini-
tion.
As an extension, ncurses allows you to set color pair <STRONG>0</STRONG> via the <STRONG>as-</STRONG>
<STRONG><A HREF="assume_default_colors.3x.html">sume_default_colors(3x)</A></STRONG> routine, or to specify the use of default col-
ors (color number <STRONG>-1</STRONG>) if you first invoke the <STRONG><A HREF="default_colors.3x.html">use_default_colors(3x)</A></STRONG>
routine.
</PRE><H3><a name="h3-init_extended_pair">init_extended_pair</a></H3><PRE>
Because <STRONG>init_pair</STRONG> uses signed <STRONG>short</STRONG>s for its parameters, that limits
color-pairs and color-values to 32767 on modern hardware. The exten-
sion <STRONG>init_extended_pair</STRONG> uses <STRONG>int</STRONG>s for the color-pair and color-value,
allowing a larger number of colors to be supported.
</PRE><H3><a name="h3-init_color">init_color</a></H3><PRE>
The <STRONG>init_color</STRONG> routine changes the definition of a color. It takes
four arguments: the number of the color to be changed followed by three
RGB values (for the amounts of red, green, and blue components).
<STRONG>o</STRONG> The first argument must be a legal color value; default colors are
not allowed here. (See the section <STRONG>Colors</STRONG> for the default color
index.)
<STRONG>o</STRONG> Each of the last three arguments must be a value in the range <STRONG>0</STRONG>
through <STRONG>1000</STRONG>.
When <STRONG>init_color</STRONG> is used, all occurrences of that color on the screen
immediately change to the new definition.
</PRE><H3><a name="h3-init_extended_color">init_extended_color</a></H3><PRE>
Because <STRONG>init_color</STRONG> uses signed <STRONG>short</STRONG>s for its parameters, that limits
color-values and their red, green, and blue components to 32767 on mod-
ern hardware. The extension <STRONG>init_extended_color</STRONG> uses <STRONG>int</STRONG>s for the col-
or value and for setting the red, green, and blue components, allowing
a larger number of colors to be supported.
</PRE><H3><a name="h3-color_content">color_content</a></H3><PRE>
The <STRONG>color_content</STRONG> routine gives programmers a way to find the intensity
of the red, green, and blue (RGB) components in a color. It requires
four arguments: the color number, and three addresses of <STRONG>short</STRONG>s for
storing the information about the amounts of red, green, and blue com-
ponents in the given color.
<STRONG>o</STRONG> The first argument must be a legal color value, i.e., <STRONG>0</STRONG> through
<STRONG>COLORS-1</STRONG>, inclusive.
<STRONG>o</STRONG> The values that are stored at the addresses pointed to by the last
three arguments are in the range <STRONG>0</STRONG> (no component) through <STRONG>1000</STRONG>
(maximum amount of component), inclusive.
</PRE><H3><a name="h3-extended_color_content">extended_color_content</a></H3><PRE>
Because <STRONG>color_content</STRONG> uses signed <STRONG>short</STRONG>s for its parameters, that lim-
its color-values and their red, green, and blue components to 32767 on
modern hardware. The extension <STRONG>extended_color_content</STRONG> uses <STRONG>int</STRONG>s for
the color value and for returning the red, green, and blue components,
allowing a larger number of colors to be supported.
</PRE><H3><a name="h3-pair_content">pair_content</a></H3><PRE>
The <STRONG>pair_content</STRONG> routine allows programmers to find out what colors a
given color-pair consists of. It requires three arguments: the color-
pair number, and two addresses of <STRONG>short</STRONG>s for storing the foreground and
the background color numbers.
<STRONG>o</STRONG> The first argument must be a legal color value, i.e., in the range
<STRONG>1</STRONG> through <STRONG>COLOR_PAIRS-1</STRONG>, inclusive.
<STRONG>o</STRONG> The values that are stored at the addresses pointed to by the sec-
ond and third arguments are in the range <STRONG>0</STRONG> through <STRONG>COLORS</STRONG>, inclu-
sive.
</PRE><H3><a name="h3-extended_pair_content">extended_pair_content</a></H3><PRE>
Because <STRONG>pair_content</STRONG> uses signed <STRONG>short</STRONG>s for its parameters, that limits
color-pair and color-values to 32767 on modern hardware. The extension
<STRONG>extended_pair_content</STRONG> uses <STRONG>int</STRONG>s for the color pair and for returning
the foreground and background colors, allowing a larger number of col-
ors to be supported.
</PRE><H3><a name="h3-reset_color_pairs">reset_color_pairs</a></H3><PRE>
The extension <STRONG>reset_color_pairs</STRONG> tells ncurses to discard all of the
color-pair information which was set with <STRONG>init_pair</STRONG>. It also touches
the current- and standard-screens, allowing an application to switch
color palettes rapidly.
</PRE><H3><a name="h3-PAIR_NUMBER">PAIR_NUMBER</a></H3><PRE>
<STRONG>PAIR_NUMBER(</STRONG><EM>attrs</EM>) extracts the color value from its <EM>attrs</EM> parameter
and returns it as a color pair number.
</PRE><H3><a name="h3-COLOR_PAIR">COLOR_PAIR</a></H3><PRE>
Its inverse <STRONG>COLOR_PAIR(</STRONG><EM>n</EM><STRONG>)</STRONG> converts a color pair number to an attribute.
Attributes can hold color pairs in the range 0 to 255. If you need a
color pair larger than that, you must use functions such as <STRONG>attr_set</STRONG>
(which pass the color pair as a separate parameter) rather than the
legacy functions such as <STRONG>attrset</STRONG>.
</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
The routines <STRONG>can_change_color</STRONG> and <STRONG>has_colors</STRONG> return <STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG>.
All other routines return the integer <STRONG>ERR</STRONG> upon failure and an <STRONG>OK</STRONG> (SVr4
specifies only "an integer value other than <STRONG>ERR</STRONG>") upon successful com-
pletion.
X/Open defines no error conditions. SVr4 does document some error con-
ditions which apply in general:
<STRONG>o</STRONG> This implementation will return <STRONG>ERR</STRONG> on attempts to use color values
outside the range <STRONG>0</STRONG> to <STRONG>COLORS</STRONG>-1 (except for the default colors ex-
tension), or use color pairs outside the range <STRONG>0</STRONG> to <STRONG>COLOR_PAIRS-1</STRONG>.
Color values used in <STRONG>init_color</STRONG> must be in the range <STRONG>0</STRONG> to <STRONG>1000</STRONG>.
An error is returned from all functions if the terminal has not
been initialized.
An error is returned from secondary functions such as <STRONG>init_pair</STRONG> if
<STRONG>start_color</STRONG> was not called.
<STRONG>o</STRONG> SVr4 does much the same, except that it returns <STRONG>ERR</STRONG> from <STRONG>pair_con-</STRONG>
<STRONG>tent</STRONG> if the pair was not initialized using <STRONG>init_pairs</STRONG> and it re-
turns <STRONG>ERR</STRONG> from <STRONG>color_content</STRONG> if the terminal does not support
changing colors.
This implementation does not return <STRONG>ERR</STRONG> for either case.
Specific functions make additional checks:
<STRONG>init_color</STRONG>
returns an error if the terminal does not support this feature,
e.g., if the <STRONG>initialize_color</STRONG> capability is absent from the
terminal description.
<STRONG>start_color</STRONG>
returns an error if the color table cannot be allocated.
</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
In the <STRONG>ncurses</STRONG> implementation, there is a separate color activation
flag, color palette, color pairs table, and associated <STRONG>COLORS</STRONG> and <STRONG>COL-</STRONG>
<STRONG>OR_PAIRS</STRONG> counts for each screen; the <STRONG>start_color</STRONG> function only affects
the current screen. The SVr4/XSI interface is not really designed with
this in mind, and historical implementations may use a single shared
color palette.
Setting an implicit background color via a color pair affects only
character cells that a character write operation explicitly touches.
To change the background color used when parts of a window are blanked
by erasing or scrolling operations, see <STRONG><A HREF="curs_bkgd.3x.html">curs_bkgd(3x)</A></STRONG>.
Several caveats apply on older x86 machines (e.g., i386, i486) with
VGA-compatible graphics:
<STRONG>o</STRONG> COLOR_YELLOW is actually brown. To get yellow, use COLOR_YELLOW
combined with the <STRONG>A_BOLD</STRONG> attribute.
<STRONG>o</STRONG> The A_BLINK attribute should in theory cause the background to go
bright. This often fails to work, and even some cards for which it
mostly works (such as the Paradise and compatibles) do the wrong
thing when you try to set a bright "yellow" background (you get a
blinking yellow foreground instead).
<STRONG>o</STRONG> Color RGB values are not settable.
</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
This implementation satisfies XSI Curses's minimum maximums for <STRONG>COLORS</STRONG>
and <STRONG>COLOR_PAIRS</STRONG>.
The <STRONG>init_pair</STRONG> routine accepts negative values of foreground and back-
ground color to support the <STRONG><A HREF="default_colors.3x.html">use_default_colors(3x)</A></STRONG> extension, but only
if that routine has been first invoked.
The assumption that <STRONG>COLOR_BLACK</STRONG> is the default background color for all
terminals can be modified using the <STRONG><A HREF="default_colors.3x.html">assume_default_colors(3x)</A></STRONG> exten-
sion.
This implementation checks the pointers, e.g., for the values returned
by <STRONG>color_content</STRONG> and <STRONG>pair_content</STRONG>, and will treat those as optional pa-
rameters when null.
X/Open Curses does not specify a limit for the number of colors and
color pairs which a terminal can support. However, in its use of <STRONG>short</STRONG>
for the parameters, it carries over SVr4's implementation detail for
the compiled terminfo database, which uses signed 16-bit numbers. This
implementation provides extended versions of those functions which use
<STRONG>short</STRONG> parameters, allowing applications to use larger color- and pair-
numbers.
The <STRONG>reset_color_pairs</STRONG> function is an extension of ncurses.
</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
<STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_initscr.3x.html">curs_initscr(3x)</A></STRONG>, <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>, <STRONG>de-</STRONG>
<STRONG><A HREF="default_colors.3x.html">fault_colors(3x)</A></STRONG>
<STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
<li><a href="#h3-Overview">Overview</a></li>
<li><a href="#h3-Color-Rendering">Color Rendering</a></li>
</ul>
</li>
<li><a href="#h2-CONSTANTS">CONSTANTS</a></li>
<li><a href="#h2-VARIABLES">VARIABLES</a>
<ul>
<li><a href="#h3-COLORS">COLORS</a></li>
<li><a href="#h3-COLOR_PAIRS">COLOR_PAIRS</a></li>
</ul>
</li>
<li><a href="#h2-FUNCTIONS">FUNCTIONS</a>
<ul>
<li><a href="#h3-start_color">start_color</a></li>
<li><a href="#h3-has_colors">has_colors</a></li>
<li><a href="#h3-can_change_color">can_change_color</a></li>
<li><a href="#h3-init_pair">init_pair</a></li>
<li><a href="#h3-init_extended_pair">init_extended_pair</a></li>
<li><a href="#h3-init_color">init_color</a></li>
<li><a href="#h3-init_extended_color">init_extended_color</a></li>
<li><a href="#h3-color_content">color_content</a></li>
<li><a href="#h3-extended_color_content">extended_color_content</a></li>
<li><a href="#h3-pair_content">pair_content</a></li>
<li><a href="#h3-extended_pair_content">extended_pair_content</a></li>
<li><a href="#h3-reset_color_pairs">reset_color_pairs</a></li>
<li><a href="#h3-PAIR_NUMBER">PAIR_NUMBER</a></li>
<li><a href="#h3-COLOR_PAIR">COLOR_PAIR</a></li>
</ul>
</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>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
</ul>
</div>
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