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diff --git a/doc/html/man/curs_color.3x.html b/doc/html/man/curs_color.3x.html index 4ebe0da04f4d..ecf9dde89f57 100644 --- a/doc/html/man/curs_color.3x.html +++ b/doc/html/man/curs_color.3x.html @@ -1,7 +1,6 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"> <!-- **************************************************************************** - * Copyright (c) 1998-2009,2010 Free Software Foundation, Inc. * + * Copyright (c) 1998-2018,2019 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 * @@ -27,155 +26,126 @@ * sale, use or other dealings in this Software without prior written * * authorization. * **************************************************************************** - * @Id: curs_color.3x,v 1.35 2010/12/20 00:50:58 tom Exp @ + * @Id: curs_color.3x,v 1.61 2019/01/20 17:04:08 tom Exp @ --> +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"> <HTML> <HEAD> +<meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> +<meta name="generator" content="Manpage converted by man2html - see https://invisible-island.net/scripts/readme.html#others_scripts"> <TITLE>curs_color 3x</TITLE> -<link rev=made href="mailto:bug-ncurses@gnu.org"> +<link rel="author" href="mailto:bug-ncurses@gnu.org"> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> </HEAD> <BODY> -<H1>curs_color 3x</H1> -<HR> +<H1 class="no-header">curs_color 3x</H1> <PRE> -<!-- Manpage converted by man2html 3.0.1 --> -<STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG> <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG> +<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>NAME</H2><PRE> - <STRONG>start_color</STRONG>, <STRONG>init_pair</STRONG>, <STRONG>init_color</STRONG>, <STRONG>has_colors</STRONG>, - <STRONG>can_change_color</STRONG>, <STRONG>color_content</STRONG>, <STRONG>pair_content</STRONG>, <STRONG>COLOR_PAIR</STRONG> - - <STRONG>curses</STRONG> color manipulation routines +</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>SYNOPSIS</H2><PRE> - <STRONG>#</STRONG> <STRONG>include</STRONG> <STRONG><curses.h></STRONG> +</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>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> + <STRONG>bool</STRONG> <STRONG>has_colors(void);</STRONG> <STRONG>bool</STRONG> <STRONG>can_change_color(void);</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>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> -</PRE> -<H2>DESCRIPTION</H2><PRE> - <STRONG>Overview</STRONG> - <STRONG>curses</STRONG> support color attributes on terminals with that ca- - pability. 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 charac- - ters are displayed). A programmer initializes a color- - pair with the routine <STRONG>init_pair</STRONG>. After it has been ini- - tialized, <STRONG>COLOR_PAIR</STRONG>(<EM>n</EM>), a macro defined in <STRONG><curses.h></STRONG>, - can be used as a new video attribute. - - If a terminal is capable of redefining colors, the pro- - grammer can use the routine <STRONG>init_color</STRONG> to change the defi- - nition of a color. The routines <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 programmer can change the colors. The routine <STRONG>col-</STRONG> - <STRONG>or_content</STRONG> allows a programmer 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. - - <STRONG>Routine</STRONG> <STRONG>Descriptions</STRONG> - 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 manipulation routine is called. It is - good practice to call this routine right after <STRONG>initscr</STRONG>. - <STRONG>start_color</STRONG> initializes eight basic colors (black, red, - green, yellow, blue, magenta, cyan, and white), and two - global variables, <STRONG>COLORS</STRONG> and <STRONG>COLOR_PAIRS</STRONG> (respectively - defining the maximum number of colors and color-pairs the - terminal can support). It also restores the colors on the - terminal to the values they had when the terminal was just - turned on. - - 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 foreground color number, and the - background color number. For portable applications: - - <STRONG>o</STRONG> The value of the first argument must be between <STRONG>1</STRONG> and - <STRONG>COLOR_PAIRS-1</STRONG>, except that if default colors are used - (see <STRONG>use_default_colors</STRONG>) the upper limit is adjusted - to allow for extra pairs which use a default color in - foreground and/or background. - - <STRONG>o</STRONG> The value of the second and third arguments must be - between 0 and <STRONG>COLORS</STRONG>. Color pair 0 is assumed to be - white on black, but is actually whatever the terminal - implements before color is initialized. It cannot be - modified by the application. - - If the color-pair was previously initialized, the screen - is refreshed and all occurrences of that color-pair are - changed to the new definition. - - As an extension, ncurses allows you to set color pair 0 - via the <STRONG>assume_default_colors</STRONG> routine, or to specify the - use of default colors (color number <STRONG>-1</STRONG>) if you first in- - voke the <STRONG>use_default_colors</STRONG> routine. - - 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). The value of the first - argument must be between <STRONG>0</STRONG> and <STRONG>COLORS</STRONG>. (See the section - <STRONG>Colors</STRONG> for the default color index.) Each of the last - three arguments must be a value between 0 and 1000. When - <STRONG>init_color</STRONG> is used, all occurrences of that color on the - screen immediately change to the new definition. - - 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 routine facilitates writing terminal- - independent programs. For example, a programmer can use - it to decide whether to use color or some other video at- - tribute. - - 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-independent programs. - - 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 components in - the given color. The value of the first argument must be - between 0 and <STRONG>COLORS</STRONG>. The values that are stored at the - addresses pointed to by the last three arguments are be- - tween 0 (no component) and 1000 (maximum amount of compo- - nent). - - 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. The value of the first argument must be - between 1 and <STRONG>COLOR_PAIRS-1</STRONG>. The values that are stored - at the addresses pointed to by the second and third argu- - ments are between 0 and <STRONG>COLORS</STRONG>. - - <STRONG>Colors</STRONG> - In <STRONG><curses.h></STRONG> the following macros are defined. These are - the default colors. <STRONG>curses</STRONG> also assumes that <STRONG>COLOR_BLACK</STRONG> - is the default background color for all terminals. + <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> @@ -186,100 +156,363 @@ <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>RETURN VALUE</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 completion. - - X/Open defines no error conditions. This implementation - will return <STRONG>ERR</STRONG> on attempts to use color values outside - the range 0 to COLORS-1 (except for the default colors ex- - tension), or use color pairs outside the range 0 to COL- - OR_PAIRS-1. Color values used in <STRONG>init_color</STRONG> must be in - the range 0 to 1000. An error is returned from all func- - tions 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. + +</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 <EM>initialize</EM><STRONG>_</STRONG><EM>color</EM> capa- - bility is absent from the terminal description. + 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 al- - located. + returns an error if the color table cannot be allocated. -</PRE> -<H2>NOTES</H2><PRE> - In the <EM>ncurses</EM> implementation, there is a separate color - activation flag, color palette, color pairs table, and as- - sociated COLORS and COLOR_PAIRS 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. - - Note that 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 386 and 486 machines 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 back- - ground 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 +</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>PORTABILITY</H2><PRE> - This implementation satisfies XSI Curses's minimum maxi- - mums for <STRONG>COLORS</STRONG> and <STRONG>COLOR_PAIRS</STRONG>. +</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 fore- - ground and background color to support the <STRONG>use_de-</STRONG> - <STRONG>fault_colors</STRONG> extension, but only if that routine has been - first invoked. + 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>as-</STRONG> - <STRONG>sume_default_colors</STRONG> extension. + 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 parameters when null. + 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. -</PRE> -<H2>SEE ALSO</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>curs_vari-</STRONG> - <STRONG><A HREF="curs_variables.3x.html">ables(3x)</A></STRONG>, <STRONG><A HREF="default_colors.3x.html">default_colors(3x)</A></STRONG> + 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> + <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG> </PRE> -<HR> -<ADDRESS> -Man(1) output converted with -<a href="http://www.oac.uci.edu/indiv/ehood/man2html.html">man2html</a> -</ADDRESS> +<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> </BODY> </HTML> |