ncurses 5.9 - patch 20150404

[ncurses.git] / man / curs_color.3x

diff --git a/man/curs_color.3x b/man/curs_color.3x
index a90a321bc7b6f56832884eaf245a7ce1c5a2b617..6be4fad4810c6005c8192407b79917fa9631b5f4 100644 (file)
--- a/man/curs_color.3x
+++ b/man/curs_color.3x
@@ -1,5 +1,5 @@
 .\"***************************************************************************
 .\"***************************************************************************

-.\" Copyright (c) 1998-2009,2010 Free Software Foundation, Inc.              *
+.\" Copyright (c) 1998-2010,2015 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            *
 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *
 .\" copy of this software and associated documentation files (the            *


@@ -26,8 +26,16 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"

-.\" $Id: curs_color.3x,v 1.30 2010/07/31 16:12:01 tom Exp $
+.\" $Id: curs_color.3x,v 1.37 2015/04/04 19:42:47 tom Exp $

 .TH curs_color 3X ""
 .TH curs_color 3X ""

+.ie \n(.g .ds `` \(lq
+.el       .ds `` ``
+.ie \n(.g .ds '' \(rq
+.el       .ds '' ''
+.de bP
+.IP \(bu 4
+..
+.ds n 5

 .na
 .hy 0
 .SH NAME
 .na
 .hy 0
 .SH NAME


@@ -43,7 +51,7 @@
 .hy
 .SH SYNOPSIS
 \fB# include <curses.h>\fR
 .hy
 .SH SYNOPSIS
 \fB# include <curses.h>\fR

-.br
+.sp

 \fBint start_color(void);\fR
 .br
 \fBint init_pair(short pair, short f, short b);\fR
 \fBint start_color(void);\fR
 .br
 \fBint init_pair(short pair, short f, short b);\fR


@@ -60,101 +68,159 @@
 .br
 .SH DESCRIPTION
 .SS Overview
 .br
 .SH DESCRIPTION
 .SS Overview

-\fBcurses\fR support color attributes on terminals with that capability.  To
-use these routines \fBstart_color\fR must be called, usually right after
-\fBinitscr\fR.  Colors are always used in pairs (referred to as color-pairs).
+\fBcurses\fR support color attributes on terminals with that capability.
+To use these routines \fBstart_color\fR must be called, usually right after
+\fBinitscr\fR.
+Colors are always used in pairs (referred to as color-pairs).

 A color-pair consists of a foreground color (for characters) and a background
 A color-pair consists of a foreground color (for characters) and a background

-color (for the blank field on which the characters are displayed).  A
-programmer initializes a color-pair with the routine \fBinit_pair\fR.  After it
-has been initialized, \fBCOLOR_PAIR\fR(\fIn\fR), a macro defined in
+color (for the blank field on which the characters are displayed).
+A programmer initializes a color-pair with the routine \fBinit_pair\fR.
+After it has been initialized, \fBCOLOR_PAIR\fR(\fIn\fR), a macro defined in

 \fB<curses.h>\fR, can be used as a new video attribute.
 .PP
 If a terminal is capable of redefining colors, the programmer can use the
 \fB<curses.h>\fR, can be used as a new video attribute.
 .PP
 If a terminal is capable of redefining colors, the programmer can use the

-routine \fBinit_color\fR to change the definition of a color.  The routines
-\fBhas_colors\fR and \fBcan_change_color\fR return \fBTRUE\fR or \fBFALSE\fR,
+routine \fBinit_color\fR to change the definition of a color.
+The routines \fBhas_colors\fR and \fBcan_change_color\fR
+return \fBTRUE\fR or \fBFALSE\fR,

 depending on whether the terminal has color capabilities and whether the
 depending on whether the terminal has color capabilities and whether the

-programmer can change the colors.  The routine \fBcolor_content\fR allows a
+programmer can change the colors.
+The routine \fBcolor_content\fR allows a

 programmer to extract the amounts of red, green, and blue components in an
 programmer to extract the amounts of red, green, and blue components in an

-initialized color.  The routine \fBpair_content\fR allows a programmer to find
+initialized color.
+The routine \fBpair_content\fR allows a programmer to find

 out how a given color-pair is currently defined.
 .SS Routine Descriptions
 out how a given color-pair is currently defined.
 .SS Routine Descriptions

-The \fBstart_color\fR 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 \fBinitscr\fR.  \fBstart_color\fR initializes
-eight basic colors (black, red, green, yellow, blue, magenta, cyan,
-and white), and two global variables, \fBCOLORS\fR and
+The \fBstart_color\fR 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 \fBinitscr\fR.
+\fBstart_color\fR does this:
+.bP
+It initializes two global variables, \fBCOLORS\fR and

 \fBCOLOR_PAIRS\fR (respectively defining the maximum number of colors
 \fBCOLOR_PAIRS\fR (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.
+and color-pairs the terminal can support).
+.bP
+It initializes the special color pair \fB0\fP to the default foreground
+and background colors.
+No other color pairs are initialized.
+.bP
+It restores the colors on the terminal to the values
+they had when the terminal was just turned on.
+.bP
+If the terminal supports the \fBinitc\fP (\fBinitialize_color\fP) capability,
+\fBstart_color\fP
+initializes its internal table representing the
+red, green and blue components of the color palette.
+.IP
+The components depend on whether the terminal uses
+CGA (aka "ANSI") or
+HLS (i.e., the \fBhls\fP (\fBhue_lightness_saturation\fP) capability is set).
+The table is initialized first for eight basic colors
+(black, red, green, yellow, blue, magenta, cyan, and white),
+and after that (if the terminal supports more than eight colors)
+the components are initialized to \fB1000\fP.
+.IP
+\fBstart_color\fP does not attempt to set the terminal's color palette
+to match its built-in table.
+An application may use \fBinit_color\fP to alter the internal table
+along with the terminal's color.
+.PP
+These limits apply to color values and color pairs.
+Values outside these limits are not legal, and may result in a runtime error:
+.bP
+\fBCOLORS\fP corresponds to the terminal database's \fBmax_colors\fP capability,
+which is typically a signed 16-bit integer (see \fBterminfo\fR(\*n)).
+.bP
+color values are expected to be in the range \fB0\fP to \fBCOLORS\-1\fP,
+inclusive (including \fB0\fP and \fBCOLORS\-1\fP).
+.bP
+a special color value \fB\-1\fP is used in certain extended functions
+to denote the \fIdefault color\fP (see \fBuse_default_colors\fP).
+.bP
+\fBCOLOR_PAIRS\fP corresponds to the terminal database's \fBmax_pairs\fP capability,
+which is typically a signed 16-bit integer (see \fBterminfo\fR(\*n)).
+.bP
+legal color pair values are in the range \fB1\fP to \fBCOLOR_PAIRS\-1\fP,
+inclusive.
+.bP
+color pair \fB0\fP is special; it denotes \*(``no color\*(''.
+.IP
+Color pair \fB0\fP 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.

 .PP
 .PP

-The \fBinit_pair\fR routine changes the definition of a color-pair.  It takes
-three arguments: the number of the color-pair to be changed, the foreground
+The \fBinit_pair\fR 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:
 color number, and the background color number.
 For portable applications:

-.TP 5
-\-
-The value of the first argument
-must be between \fB1\fR and \fBCOLOR_PAIRS\-1\fR,
-except that if default colors are used (see \fBuse_default_colors\fP)
+.bP
+The first argument must be a legal color pair value.
+If default colors are used (see \fBuse_default_colors\fP)

 the upper limit is adjusted to allow for extra pairs which use
 a default color in foreground and/or background.
 the upper limit is adjusted to allow for extra pairs which use
 a default color in foreground and/or background.

-.TP 5
-\-
-The value of the second and
-third arguments must be between 0 and \fBCOLORS\fR.
-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.
+.bP
+The second and third arguments must be legal color values.

 .PP
 .PP

-If the color-pair was previously
-initialized, the screen is refreshed and all occurrences of that color-pair
+If the color-pair was previously initialized,
+the screen is refreshed and all occurrences of that color-pair

 are changed to the new definition.
 .PP
 are changed to the new definition.
 .PP

-As an extension, ncurses allows you to set color pair 0 via
+As an extension, ncurses allows you to set color pair \fB0\fP via

 the \fBassume_default_colors\fR routine, or to specify the use of
 default colors (color number \fB\-1\fR) if you first invoke the
 \fBuse_default_colors\fR routine.
 .PP
 the \fBassume_default_colors\fR routine, or to specify the use of
 default colors (color number \fB\-1\fR) if you first invoke the
 \fBuse_default_colors\fR routine.
 .PP

-The \fBinit_color\fR 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 \fB0\fR and \fBCOLORS\fR.  (See the section
-\fBColors\fR for the default color index.)  Each of the last three arguments
-must be a value between 0 and 1000.  When \fBinit_color\fR is used, all
+The \fBinit_color\fR 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 first argument must be a legal color value;
+default colors are not allowed here.
+(See the section \fBColors\fR for the default color index.)
+Each of the last three arguments
+must be a value in the range \fB0\fP through \fB1000\fP.
+When \fBinit_color\fR is used, all

 occurrences of that color on the screen immediately change to the new
 definition.
 .PP
 occurrences of that color on the screen immediately change to the new
 definition.
 .PP

-The \fBhas_colors\fR routine requires no arguments.  It returns \fBTRUE\fR if
-the terminal can manipulate colors; otherwise, it returns \fBFALSE\fR.  This
-routine facilitates writing terminal-independent programs.  For example, a
-programmer can use it to decide whether to use color or some other video
-attribute.
+The \fBhas_colors\fR routine requires no arguments.
+It returns \fBTRUE\fR if
+the terminal can manipulate colors; otherwise, it returns \fBFALSE\fR.
+This routine facilitates writing terminal-independent programs.
+For example, a programmer can use it to decide
+whether to use color or some other video attribute.

 .PP
 .PP

-The \fBcan_change_color\fR routine requires no arguments.  It returns
-\fBTRUE\fR if the terminal supports colors and can change their definitions;
-other, it returns \fBFALSE\fR.  This routine facilitates writing
-terminal-independent programs.
+The \fBcan_change_color\fR routine requires no arguments.
+It returns \fBTRUE\fR if the terminal supports colors
+and can change their definitions;
+other, it returns \fBFALSE\fR.
+This routine facilitates writing terminal-independent programs.

 .PP
 The \fBcolor_content\fR routine gives programmers a way to find the intensity
 .PP
 The \fBcolor_content\fR 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 \fBshort\fRs for storing
+of the red, green, and blue (RGB) components in a color.
+It requires four arguments: the color number, and three addresses
+of \fBshort\fRs for storing

 the information about the amounts of red, green, and blue components in the
 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
-\fBCOLORS\fR.  The values that are stored at the addresses pointed to by the
-last three arguments are between 0 (no component) and 1000 (maximum amount of
-component).
+given color.
+The first argument must be a legal color value, i.e.,
+\fB0\fP through \fBCOLORS\-1\fP, inclusive.
+The values that are stored at the addresses pointed to by the
+last three arguments are in the range
+\fB0\fP (no component) through \fB1000\fP (maximum amount of component), inclusive.

 .PP
 The \fBpair_content\fR routine allows programmers to find out what colors a
 .PP
 The \fBpair_content\fR routine allows programmers to find out what colors a

-given color-pair consists of.  It requires three arguments: the color-pair
+given color-pair consists of.
+It requires three arguments: the color-pair

 number, and two addresses of \fBshort\fRs for storing the foreground and the
 number, and two addresses of \fBshort\fRs for storing the foreground and the

-background color numbers.  The value of the first argument must be between 1
-and \fBCOLOR_PAIRS\-1\fR.  The values that are stored at the addresses pointed
-to by the second and third arguments are between 0 and \fBCOLORS\fR.
+background color numbers.
+The first argument must be a legal color value,
+i.e., in the range \fB1\fP through \fBCOLOR_PAIRS\-1\fR, inclusive.
+The values that are stored at the addresses pointed
+to by the second and third arguments are in the
+range \fB0\fP through \fBCOLORS\fR, inclusive.

 .SS Colors
 .SS Colors

-In \fB<curses.h>\fR the following macros are defined.  These are the default
-colors.  \fBcurses\fR also assumes that \fBCOLOR_BLACK\fR is the default
+In \fB<curses.h>\fR the following macros are defined.
+These are the default colors.
+\fBcurses\fR also assumes that \fBCOLOR_BLACK\fR is the default

 background color for all terminals.
 .PP
 .nf
 background color for all terminals.
 .PP
 .nf


@@ -177,15 +243,15 @@ completion.
 .PP
 X/Open defines no error conditions.
 This implementation will return \fBERR\fR on attempts to
 .PP
 X/Open defines no error conditions.
 This implementation will return \fBERR\fR on attempts to

-use color values outside the range 0 to COLORS\-1
+use color values outside the range \fB0\fP to COLORS\-1

 (except for the default colors extension),
 (except for the default colors extension),

-or use color pairs outside the range 0 to COLOR_PAIR\-1.
-Color values used in \fBinit_color\fP must be in the range 0 to 1000.
+or use color pairs outside the range \fB0\fP to \fBCOLOR_PAIRS\-1\fP.
+Color values used in \fBinit_color\fP must be in the range \fB0\fP to \fB1000\fP.

 An error is returned from all functions
 if the terminal has not been initialized.
 An error is returned from secondary functions such as \fBinit_pair\fP
 if \fBstart_color\fP was not called.
 An error is returned from all functions
 if the terminal has not been initialized.
 An error is returned from secondary functions such as \fBinit_pair\fP
 if \fBstart_color\fP was not called.

-.RS
+.RS 3

 .TP 5
 \fBinit_color\fP
 returns an error if the terminal does not support
 .TP 5
 \fBinit_color\fP
 returns an error if the terminal does not support


@@ -193,34 +259,33 @@ this feature, e.g., if the \fIinitialize_color\fP capability is absent
 from the terminal description.
 .TP 5
 \fBstart_color\fP
 from the terminal description.
 .TP 5
 \fBstart_color\fP

-returns an error
-If the color table cannot be allocated.
+returns an error if the color table cannot be allocated.

 .RE
 .SH NOTES
 In the \fIncurses\fR implementation, there is a separate color activation flag,
 color palette, color pairs table, and associated COLORS and COLOR_PAIRS counts
 for each screen; the \fBstart_color\fR function only affects the current
 .RE
 .SH NOTES
 In the \fIncurses\fR implementation, there is a separate color activation flag,
 color palette, color pairs table, and associated COLORS and COLOR_PAIRS counts
 for each screen; the \fBstart_color\fR function only affects the current

-screen.  The SVr4/XSI interface is not really designed with this in mind, and
+screen.
+The SVr4/XSI interface is not really designed with this in mind, and

 historical implementations may use a single shared color palette.
 .PP
 Note that setting an implicit background color via a color pair affects only
 historical implementations may use a single shared color palette.
 .PP
 Note that setting an implicit background color via a color pair affects only

-character cells that a character write operation explicitly touches.  To change
+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 \fBcurs_bkgd\fR(3X).
 .PP
 Several caveats apply on 386 and 486 machines with VGA-compatible graphics:
 the background color used when parts of a window are blanked by erasing or
 scrolling operations, see \fBcurs_bkgd\fR(3X).
 .PP
 Several caveats apply on 386 and 486 machines with VGA-compatible graphics:

-.TP 5
-\-
-COLOR_YELLOW is actually brown.  To get yellow, use COLOR_YELLOW combined with
-the \fBA_BOLD\fR attribute.
-.TP 5
-\-
-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
+.bP
+COLOR_YELLOW is actually brown.
+To get yellow, use COLOR_YELLOW combined with the \fBA_BOLD\fR attribute.
+.bP
+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).
 Paradise and compatibles) do the wrong thing when you try to set a bright
 "yellow" background (you get a blinking yellow foreground instead).

-.TP 5
-\-
+.bP

 Color RGB values are not settable.
 .SH PORTABILITY
 This implementation satisfies XSI Curses's minimum maximums
 Color RGB values are not settable.
 .SH PORTABILITY
 This implementation satisfies XSI Curses's minimum maximums


@@ -242,10 +307,5 @@ and will treat those as optional parameters when null.
 \fBcurses\fR(3X),
 \fBcurs_initscr\fR(3X),
 \fBcurs_attr\fR(3X),
 \fBcurses\fR(3X),
 \fBcurs_initscr\fR(3X),
 \fBcurs_attr\fR(3X),

+\fBcurs_variables\fR(3X),

 \fBdefault_colors\fR(3X)
 \fBdefault_colors\fR(3X)

-.\"#
-.\"# The following sets edit modes for GNU EMACS
-.\"# Local Variables:
-.\"# mode:nroff
-.\"# fill-column:79
-.\"# End: