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30 * @Id: curs_color.3x,v 1.63 2020/10/24 09:35:23 tom Exp @
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42 <H1 class="no-header">curs_color 3x</H1>
44 <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG> <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>
49 </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
50 <STRONG>start_color</STRONG>, <STRONG>has_colors</STRONG>, <STRONG>can_change_color</STRONG>, <STRONG>init_pair</STRONG>, <STRONG>init_color</STRONG>,
51 <STRONG>init_extended_pair</STRONG>, <STRONG>init_extended_color</STRONG>, <STRONG>color_content</STRONG>, <STRONG>pair_content</STRONG>,
52 <STRONG>extended_color_content</STRONG>, <STRONG>extended_pair_content</STRONG>, <STRONG>reset_color_pairs</STRONG>,
53 <STRONG>COLOR_PAIR</STRONG>, <STRONG>PAIR_NUMBER</STRONG> - <STRONG>curses</STRONG> color manipulation routines
56 </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
57 <STRONG>#include</STRONG> <STRONG><curses.h></STRONG>
59 <STRONG>int</STRONG> <STRONG>start_color(void);</STRONG>
61 <STRONG>bool</STRONG> <STRONG>has_colors(void);</STRONG>
62 <STRONG>bool</STRONG> <STRONG>can_change_color(void);</STRONG>
64 <STRONG>int</STRONG> <STRONG>init_pair(short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>f</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>b</EM><STRONG>);</STRONG>
65 <STRONG>int</STRONG> <STRONG>init_color(short</STRONG> <EM>color</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>r</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>g</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>b</EM><STRONG>);</STRONG>
67 <STRONG>int</STRONG> <STRONG>init_extended_pair(int</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>f</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>b</EM><STRONG>);</STRONG>
68 <STRONG>int</STRONG> <STRONG>init_extended_color(int</STRONG> <EM>color</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>r</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>g</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>b</EM><STRONG>);</STRONG>
70 <STRONG>int</STRONG> <STRONG>color_content(short</STRONG> <EM>color</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <STRONG>*</STRONG><EM>r</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <STRONG>*</STRONG><EM>g</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <STRONG>*</STRONG><EM>b</EM><STRONG>);</STRONG>
71 <STRONG>int</STRONG> <STRONG>pair_content(short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <STRONG>*</STRONG><EM>f</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <STRONG>*</STRONG><EM>b</EM><STRONG>);</STRONG>
73 <STRONG>int</STRONG> <STRONG>extended_color_content(int</STRONG> <EM>color</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>*</STRONG><EM>r</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>*</STRONG><EM>g</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>*</STRONG><EM>b</EM><STRONG>);</STRONG>
74 <STRONG>int</STRONG> <STRONG>extended_pair_content(int</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>*</STRONG><EM>f</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <STRONG>*</STRONG><EM>b</EM><STRONG>);</STRONG>
77 <STRONG>void</STRONG> <STRONG>reset_color_pairs(void);</STRONG>
79 <STRONG>int</STRONG> <STRONG>COLOR_PAIR(int</STRONG> <EM>n</EM><STRONG>);</STRONG>
80 <STRONG>PAIR_NUMBER(</STRONG><EM>attrs</EM><STRONG>);</STRONG>
83 </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
85 </PRE><H3><a name="h3-Overview">Overview</a></H3><PRE>
86 <STRONG>curses</STRONG> supports color attributes on terminals with that capability. To
87 use these routines <STRONG>start_color</STRONG> must be called, usually right after
88 <STRONG>initscr</STRONG>. Colors are always used in pairs (referred to as color-pairs).
89 A color-pair consists of a foreground color (for characters) and a
90 background color (for the blank field on which the characters are dis-
91 played). A programmer initializes a color-pair with the routine
92 <STRONG>init_pair</STRONG>. After it has been initialized, <STRONG>COLOR_PAIR</STRONG>(<EM>n</EM>) can be used to
93 convert the pair to a video attribute.
95 If a terminal is capable of redefining colors, the programmer can use
96 the routine <STRONG>init_color</STRONG> to change the definition of a color. The rou-
97 tines <STRONG>has_colors</STRONG> and <STRONG>can_change_color</STRONG> return <STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG>, depending
98 on whether the terminal has color capabilities and whether the program-
99 mer can change the colors. The routine <STRONG>color_content</STRONG> allows a program-
100 mer to extract the amounts of red, green, and blue components in an
101 initialized color. The routine <STRONG>pair_content</STRONG> allows a programmer to
102 find out how a given color-pair is currently defined.
105 </PRE><H3><a name="h3-Color-Rendering">Color Rendering</a></H3><PRE>
106 The <STRONG>curses</STRONG> library combines these inputs to produce the actual fore-
107 ground and background colors shown on the screen:
109 <STRONG>o</STRONG> per-character video attributes (e.g., via <STRONG>waddch</STRONG>),
111 <STRONG>o</STRONG> the window attribute (e.g., by <STRONG>wattrset</STRONG>), and
113 <STRONG>o</STRONG> the background character (e.g., <STRONG>wbkgdset</STRONG>).
115 Per-character and window attributes are usually set by a parameter con-
116 taining video attributes including a color pair value. Some functions
117 such as <STRONG>wattr_set</STRONG> use a separate parameter which is the color pair num-
120 The background character is a special case: it includes a character
121 value, just as if it were passed to <STRONG>waddch</STRONG>.
123 The <STRONG>curses</STRONG> library does the actual work of combining these color pairs
124 in an internal function called from <STRONG>waddch</STRONG>:
126 <STRONG>o</STRONG> If the parameter passed to <STRONG>waddch</STRONG> is <EM>blank</EM>, and it uses the special
129 <STRONG>o</STRONG> <STRONG>curses</STRONG> next checks the window attribute.
131 <STRONG>o</STRONG> If the window attribute does not use color pair 0, <STRONG>curses</STRONG> uses
132 the color pair from the window attribute.
134 <STRONG>o</STRONG> Otherwise, <STRONG>curses</STRONG> uses the background character.
136 <STRONG>o</STRONG> If the parameter passed to <STRONG>waddch</STRONG> is <EM>not</EM> <EM>blank</EM>, or it does not use
137 the special color pair 0, <STRONG>curses</STRONG> prefers the color pair from the
138 parameter, if it is nonzero. Otherwise, it tries the window at-
139 tribute next, and finally the background character.
141 Some <STRONG>curses</STRONG> functions such as <STRONG>wprintw</STRONG> call <STRONG>waddch</STRONG>. Those do not com-
142 bine its parameter with a color pair. Consequently those calls use on-
143 ly the window attribute or the background character.
146 </PRE><H2><a name="h2-CONSTANTS">CONSTANTS</a></H2><PRE>
147 In <STRONG><curses.h></STRONG> the following macros are defined. These are the standard
148 colors (ISO-6429). <STRONG>curses</STRONG> also assumes that <STRONG>COLOR_BLACK</STRONG> is the default
149 background color for all terminals.
151 <STRONG>COLOR_BLACK</STRONG>
152 <STRONG>COLOR_RED</STRONG>
153 <STRONG>COLOR_GREEN</STRONG>
154 <STRONG>COLOR_YELLOW</STRONG>
155 <STRONG>COLOR_BLUE</STRONG>
156 <STRONG>COLOR_MAGENTA</STRONG>
157 <STRONG>COLOR_CYAN</STRONG>
158 <STRONG>COLOR_WHITE</STRONG>
160 Some terminals support more than the eight (8) "ANSI" colors. There
161 are no standard names for those additional colors.
164 </PRE><H2><a name="h2-VARIABLES">VARIABLES</a></H2><PRE>
166 </PRE><H3><a name="h3-COLORS">COLORS</a></H3><PRE>
167 is initialized by <STRONG>start_color</STRONG> to the maximum number of colors the ter-
171 </PRE><H3><a name="h3-COLOR_PAIRS">COLOR_PAIRS</a></H3><PRE>
172 is initialized by <STRONG>start_color</STRONG> to the maximum number of color pairs the
173 terminal can support.
176 </PRE><H2><a name="h2-FUNCTIONS">FUNCTIONS</a></H2><PRE>
178 </PRE><H3><a name="h3-start_color">start_color</a></H3><PRE>
179 The <STRONG>start_color</STRONG> routine requires no arguments. It must be called if
180 the programmer wants to use colors, and before any other color manipu-
181 lation routine is called. It is good practice to call this routine
182 right after <STRONG>initscr</STRONG>. <STRONG>start_color</STRONG> does this:
184 <STRONG>o</STRONG> It initializes two global variables, <STRONG>COLORS</STRONG> and <STRONG>COLOR_PAIRS</STRONG> (re-
185 spectively defining the maximum number of colors and color-pairs
186 the terminal can support).
188 <STRONG>o</STRONG> It initializes the special color pair <STRONG>0</STRONG> to the default foreground
189 and background colors. No other color pairs are initialized.
191 <STRONG>o</STRONG> It restores the colors on the terminal to the values they had when
192 the terminal was just turned on.
194 <STRONG>o</STRONG> If the terminal supports the <STRONG>initc</STRONG> (<STRONG>initialize_color</STRONG>) capability,
195 <STRONG>start_color</STRONG> initializes its internal table representing the red,
196 green, and blue components of the color palette.
198 The components depend on whether the terminal uses CGA (aka "ANSI")
199 or HLS (i.e., the <STRONG>hls</STRONG> (<STRONG>hue_lightness_saturation</STRONG>) capability is
200 set). The table is initialized first for eight basic colors
201 (black, red, green, yellow, blue, magenta, cyan, and white), using
202 weights that depend upon the CGA/HLS choice. For "ANSI" colors the
203 weights are <STRONG>680</STRONG> or <STRONG>0</STRONG> depending on whether the corresponding red,
204 green, or blue component is used or not. That permits using <STRONG>1000</STRONG>
205 to represent bold/bright colors. After the initial eight colors
206 (if the terminal supports more than eight colors) the components
207 are initialized using the same pattern, but with weights of <STRONG>1000</STRONG>.
208 SVr4 uses a similar scheme, but uses <STRONG>1000</STRONG> for the components of the
209 initial eight colors.
211 <STRONG>start_color</STRONG> does not attempt to set the terminal's color palette to
212 match its built-in table. An application may use <STRONG>init_color</STRONG> to al-
213 ter the internal table along with the terminal's color.
215 These limits apply to color values and color pairs. Values outside
216 these limits are not legal, and may result in a runtime error:
218 <STRONG>o</STRONG> <STRONG>COLORS</STRONG> corresponds to the terminal database's <STRONG>max_colors</STRONG> capabili-
219 ty, (see <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>).
221 <STRONG>o</STRONG> color values are expected to be in the range <STRONG>0</STRONG> to <STRONG>COLORS-1</STRONG>, inclu-
222 sive (including <STRONG>0</STRONG> and <STRONG>COLORS-1</STRONG>).
224 <STRONG>o</STRONG> a special color value <STRONG>-1</STRONG> is used in certain extended functions to
225 denote the <EM>default</EM> <EM>color</EM> (see <STRONG><A HREF="default_colors.3x.html">use_default_colors(3x)</A></STRONG>).
227 <STRONG>o</STRONG> <STRONG>COLOR_PAIRS</STRONG> corresponds to the terminal database's <STRONG>max_pairs</STRONG> capa-
228 bility, (see <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>).
230 <STRONG>o</STRONG> legal color pair values are in the range <STRONG>1</STRONG> to <STRONG>COLOR_PAIRS-1</STRONG>, inclu-
233 <STRONG>o</STRONG> color pair <STRONG>0</STRONG> is special; it denotes "no color".
235 Color pair <STRONG>0</STRONG> is assumed to be white on black, but is actually what-
236 ever the terminal implements before color is initialized. It can-
237 not be modified by the application.
240 </PRE><H3><a name="h3-has_colors">has_colors</a></H3><PRE>
241 The <STRONG>has_colors</STRONG> routine requires no arguments. It returns <STRONG>TRUE</STRONG> if the
242 terminal can manipulate colors; otherwise, it returns <STRONG>FALSE</STRONG>. This rou-
243 tine facilitates writing terminal-independent programs. For example, a
244 programmer can use it to decide whether to use color or some other
248 </PRE><H3><a name="h3-can_change_color">can_change_color</a></H3><PRE>
249 The <STRONG>can_change_color</STRONG> routine requires no arguments. It returns <STRONG>TRUE</STRONG> if
250 the terminal supports colors and can change their definitions; other,
251 it returns <STRONG>FALSE</STRONG>. This routine facilitates writing terminal-indepen-
255 </PRE><H3><a name="h3-init_pair">init_pair</a></H3><PRE>
256 The <STRONG>init_pair</STRONG> routine changes the definition of a color-pair. It takes
257 three arguments: the number of the color-pair to be changed, the fore-
258 ground color number, and the background color number. For portable ap-
261 <STRONG>o</STRONG> The first argument must be a legal color pair value. If default
262 colors are used (see <STRONG><A HREF="default_colors.3x.html">use_default_colors(3x)</A></STRONG>) the upper limit is ad-
263 justed to allow for extra pairs which use a default color in fore-
264 ground and/or background.
266 <STRONG>o</STRONG> The second and third arguments must be legal color values.
268 If the color-pair was previously initialized, the screen is refreshed
269 and all occurrences of that color-pair are changed to the new defini-
272 As an extension, ncurses allows you to set color pair <STRONG>0</STRONG> via the <STRONG>as-</STRONG>
273 <STRONG><A HREF="assume_default_colors.3x.html">sume_default_colors(3x)</A></STRONG> routine, or to specify the use of default col-
274 ors (color number <STRONG>-1</STRONG>) if you first invoke the <STRONG><A HREF="default_colors.3x.html">use_default_colors(3x)</A></STRONG>
278 </PRE><H3><a name="h3-init_extended_pair">init_extended_pair</a></H3><PRE>
279 Because <STRONG>init_pair</STRONG> uses signed <STRONG>short</STRONG>s for its parameters, that limits
280 color-pairs and color-values to 32767 on modern hardware. The exten-
281 sion <STRONG>init_extended_pair</STRONG> uses <STRONG>int</STRONG>s for the color-pair and color-value,
282 allowing a larger number of colors to be supported.
285 </PRE><H3><a name="h3-init_color">init_color</a></H3><PRE>
286 The <STRONG>init_color</STRONG> routine changes the definition of a color. It takes
287 four arguments: the number of the color to be changed followed by three
288 RGB values (for the amounts of red, green, and blue components).
290 <STRONG>o</STRONG> The first argument must be a legal color value; default colors are
291 not allowed here. (See the section <STRONG>Colors</STRONG> for the default color
294 <STRONG>o</STRONG> Each of the last three arguments must be a value in the range <STRONG>0</STRONG>
295 through <STRONG>1000</STRONG>.
297 When <STRONG>init_color</STRONG> is used, all occurrences of that color on the screen
298 immediately change to the new definition.
301 </PRE><H3><a name="h3-init_extended_color">init_extended_color</a></H3><PRE>
302 Because <STRONG>init_color</STRONG> uses signed <STRONG>short</STRONG>s for its parameters, that limits
303 color-values and their red, green, and blue components to 32767 on mod-
304 ern hardware. The extension <STRONG>init_extended_color</STRONG> uses <STRONG>int</STRONG>s for the col-
305 or value and for setting the red, green, and blue components, allowing
306 a larger number of colors to be supported.
309 </PRE><H3><a name="h3-color_content">color_content</a></H3><PRE>
310 The <STRONG>color_content</STRONG> routine gives programmers a way to find the intensity
311 of the red, green, and blue (RGB) components in a color. It requires
312 four arguments: the color number, and three addresses of <STRONG>short</STRONG>s for
313 storing the information about the amounts of red, green, and blue com-
314 ponents in the given color.
316 <STRONG>o</STRONG> The first argument must be a legal color value, i.e., <STRONG>0</STRONG> through
317 <STRONG>COLORS-1</STRONG>, inclusive.
319 <STRONG>o</STRONG> The values that are stored at the addresses pointed to by the last
320 three arguments are in the range <STRONG>0</STRONG> (no component) through <STRONG>1000</STRONG>
321 (maximum amount of component), inclusive.
324 </PRE><H3><a name="h3-extended_color_content">extended_color_content</a></H3><PRE>
325 Because <STRONG>color_content</STRONG> uses signed <STRONG>short</STRONG>s for its parameters, that lim-
326 its color-values and their red, green, and blue components to 32767 on
327 modern hardware. The extension <STRONG>extended_color_content</STRONG> uses <STRONG>int</STRONG>s for
328 the color value and for returning the red, green, and blue components,
329 allowing a larger number of colors to be supported.
332 </PRE><H3><a name="h3-pair_content">pair_content</a></H3><PRE>
333 The <STRONG>pair_content</STRONG> routine allows programmers to find out what colors a
334 given color-pair consists of. It requires three arguments: the color-
335 pair number, and two addresses of <STRONG>short</STRONG>s for storing the foreground and
336 the background color numbers.
338 <STRONG>o</STRONG> The first argument must be a legal color value, i.e., in the range
339 <STRONG>1</STRONG> through <STRONG>COLOR_PAIRS-1</STRONG>, inclusive.
341 <STRONG>o</STRONG> The values that are stored at the addresses pointed to by the sec-
342 ond and third arguments are in the range <STRONG>0</STRONG> through <STRONG>COLORS</STRONG>, inclu-
346 </PRE><H3><a name="h3-extended_pair_content">extended_pair_content</a></H3><PRE>
347 Because <STRONG>pair_content</STRONG> uses signed <STRONG>short</STRONG>s for its parameters, that limits
348 color-pair and color-values to 32767 on modern hardware. The extension
349 <STRONG>extended_pair_content</STRONG> uses <STRONG>int</STRONG>s for the color pair and for returning
350 the foreground and background colors, allowing a larger number of col-
354 </PRE><H3><a name="h3-reset_color_pairs">reset_color_pairs</a></H3><PRE>
355 The extension <STRONG>reset_color_pairs</STRONG> tells ncurses to discard all of the
356 color-pair information which was set with <STRONG>init_pair</STRONG>. It also touches
357 the current- and standard-screens, allowing an application to switch
358 color palettes rapidly.
361 </PRE><H3><a name="h3-PAIR_NUMBER">PAIR_NUMBER</a></H3><PRE>
362 <STRONG>PAIR_NUMBER(</STRONG><EM>attrs</EM>) extracts the color value from its <EM>attrs</EM> parameter
363 and returns it as a color pair number.
366 </PRE><H3><a name="h3-COLOR_PAIR">COLOR_PAIR</a></H3><PRE>
367 Its inverse <STRONG>COLOR_PAIR(</STRONG><EM>n</EM><STRONG>)</STRONG> converts a color pair number to an attribute.
368 Attributes can hold color pairs in the range 0 to 255. If you need a
369 color pair larger than that, you must use functions such as <STRONG>attr_set</STRONG>
370 (which pass the color pair as a separate parameter) rather than the
371 legacy functions such as <STRONG>attrset</STRONG>.
374 </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
375 The routines <STRONG>can_change_color</STRONG> and <STRONG>has_colors</STRONG> return <STRONG>TRUE</STRONG> or <STRONG>FALSE</STRONG>.
377 All other routines return the integer <STRONG>ERR</STRONG> upon failure and an <STRONG>OK</STRONG> (SVr4
378 specifies only "an integer value other than <STRONG>ERR</STRONG>") upon successful com-
381 X/Open defines no error conditions. SVr4 does document some error con-
382 ditions which apply in general:
384 <STRONG>o</STRONG> This implementation will return <STRONG>ERR</STRONG> on attempts to use color values
385 outside the range <STRONG>0</STRONG> to <STRONG>COLORS</STRONG>-1 (except for the default colors ex-
386 tension), or use color pairs outside the range <STRONG>0</STRONG> to <STRONG>COLOR_PAIRS-1</STRONG>.
388 Color values used in <STRONG>init_color</STRONG> must be in the range <STRONG>0</STRONG> to <STRONG>1000</STRONG>.
390 An error is returned from all functions if the terminal has not
393 An error is returned from secondary functions such as <STRONG>init_pair</STRONG> if
394 <STRONG>start_color</STRONG> was not called.
396 <STRONG>o</STRONG> SVr4 does much the same, except that it returns <STRONG>ERR</STRONG> from <STRONG>pair_con-</STRONG>
397 <STRONG>tent</STRONG> if the pair was not initialized using <STRONG>init_pairs</STRONG> and it re-
398 turns <STRONG>ERR</STRONG> from <STRONG>color_content</STRONG> if the terminal does not support
401 This implementation does not return <STRONG>ERR</STRONG> for either case.
403 Specific functions make additional checks:
405 <STRONG>init_color</STRONG>
406 returns an error if the terminal does not support this feature,
407 e.g., if the <STRONG>initialize_color</STRONG> capability is absent from the
408 terminal description.
410 <STRONG>start_color</STRONG>
411 returns an error if the color table cannot be allocated.
414 </PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
415 In the <STRONG>ncurses</STRONG> implementation, there is a separate color activation
416 flag, color palette, color pairs table, and associated <STRONG>COLORS</STRONG> and <STRONG>COL-</STRONG>
417 <STRONG>OR_PAIRS</STRONG> counts for each screen; the <STRONG>start_color</STRONG> function only affects
418 the current screen. The SVr4/XSI interface is not really designed with
419 this in mind, and historical implementations may use a single shared
422 Setting an implicit background color via a color pair affects only
423 character cells that a character write operation explicitly touches.
424 To change the background color used when parts of a window are blanked
425 by erasing or scrolling operations, see <STRONG><A HREF="curs_bkgd.3x.html">curs_bkgd(3x)</A></STRONG>.
427 Several caveats apply on older x86 machines (e.g., i386, i486) with
428 VGA-compatible graphics:
430 <STRONG>o</STRONG> COLOR_YELLOW is actually brown. To get yellow, use COLOR_YELLOW
431 combined with the <STRONG>A_BOLD</STRONG> attribute.
433 <STRONG>o</STRONG> The A_BLINK attribute should in theory cause the background to go
434 bright. This often fails to work, and even some cards for which it
435 mostly works (such as the Paradise and compatibles) do the wrong
436 thing when you try to set a bright "yellow" background (you get a
437 blinking yellow foreground instead).
439 <STRONG>o</STRONG> Color RGB values are not settable.
442 </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
443 This implementation satisfies XSI Curses's minimum maximums for <STRONG>COLORS</STRONG>
444 and <STRONG>COLOR_PAIRS</STRONG>.
446 The <STRONG>init_pair</STRONG> routine accepts negative values of foreground and back-
447 ground color to support the <STRONG><A HREF="default_colors.3x.html">use_default_colors(3x)</A></STRONG> extension, but only
448 if that routine has been first invoked.
450 The assumption that <STRONG>COLOR_BLACK</STRONG> is the default background color for all
451 terminals can be modified using the <STRONG><A HREF="default_colors.3x.html">assume_default_colors(3x)</A></STRONG> exten-
454 This implementation checks the pointers, e.g., for the values returned
455 by <STRONG>color_content</STRONG> and <STRONG>pair_content</STRONG>, and will treat those as optional pa-
458 X/Open Curses does not specify a limit for the number of colors and
459 color pairs which a terminal can support. However, in its use of <STRONG>short</STRONG>
460 for the parameters, it carries over SVr4's implementation detail for
461 the compiled terminfo database, which uses signed 16-bit numbers. This
462 implementation provides extended versions of those functions which use
463 <STRONG>short</STRONG> parameters, allowing applications to use larger color- and pair-
466 The <STRONG>reset_color_pairs</STRONG> function is an extension of ncurses.
469 </PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
470 <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>
471 <STRONG><A HREF="default_colors.3x.html">fault_colors(3x)</A></STRONG>
475 <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>
479 <li><a href="#h2-NAME">NAME</a></li>
480 <li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
481 <li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
483 <li><a href="#h3-Overview">Overview</a></li>
484 <li><a href="#h3-Color-Rendering">Color Rendering</a></li>
487 <li><a href="#h2-CONSTANTS">CONSTANTS</a></li>
488 <li><a href="#h2-VARIABLES">VARIABLES</a>
490 <li><a href="#h3-COLORS">COLORS</a></li>
491 <li><a href="#h3-COLOR_PAIRS">COLOR_PAIRS</a></li>
494 <li><a href="#h2-FUNCTIONS">FUNCTIONS</a>
496 <li><a href="#h3-start_color">start_color</a></li>
497 <li><a href="#h3-has_colors">has_colors</a></li>
498 <li><a href="#h3-can_change_color">can_change_color</a></li>
499 <li><a href="#h3-init_pair">init_pair</a></li>
500 <li><a href="#h3-init_extended_pair">init_extended_pair</a></li>
501 <li><a href="#h3-init_color">init_color</a></li>
502 <li><a href="#h3-init_extended_color">init_extended_color</a></li>
503 <li><a href="#h3-color_content">color_content</a></li>
504 <li><a href="#h3-extended_color_content">extended_color_content</a></li>
505 <li><a href="#h3-pair_content">pair_content</a></li>
506 <li><a href="#h3-extended_pair_content">extended_pair_content</a></li>
507 <li><a href="#h3-reset_color_pairs">reset_color_pairs</a></li>
508 <li><a href="#h3-PAIR_NUMBER">PAIR_NUMBER</a></li>
509 <li><a href="#h3-COLOR_PAIR">COLOR_PAIR</a></li>
512 <li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
513 <li><a href="#h2-NOTES">NOTES</a></li>
514 <li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
515 <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>