.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: curs_color.3x,v 1.66 2021/09/04 19:42:20 tom Exp $
+.\" $Id: curs_color.3x,v 1.67 2021/12/25 17:39:16 tom Exp $
.TH curs_color 3X ""
.ie \n(.g .ds `` \(lq
.el .ds `` ``
.na
.hy 0
.SH NAME
-\fBstart_color\fR,
-\fBhas_colors\fR,
-\fBcan_change_color\fR,
-\fBinit_pair\fR,
-\fBinit_color\fR,
-\fBinit_extended_pair\fR,
-\fBinit_extended_color\fR,
-\fBcolor_content\fR,
-\fBpair_content\fR,
-\fBextended_color_content\fR,
-\fBextended_pair_content\fR,
-\fBreset_color_pairs\fR,
-\fBCOLOR_PAIR\fR,
-\fBPAIR_NUMBER\fR \- \fBcurses\fR color manipulation routines
+\fBstart_color\fP,
+\fBhas_colors\fP,
+\fBcan_change_color\fP,
+\fBinit_pair\fP,
+\fBinit_color\fP,
+\fBinit_extended_pair\fP,
+\fBinit_extended_color\fP,
+\fBcolor_content\fP,
+\fBpair_content\fP,
+\fBextended_color_content\fP,
+\fBextended_pair_content\fP,
+\fBreset_color_pairs\fP,
+\fBCOLOR_PAIR\fP,
+\fBPAIR_NUMBER\fP \- \fBcurses\fP color manipulation routines
.ad
.hy
.SH SYNOPSIS
-\fB#include <curses.h>\fR
+\fB#include <curses.h>\fP
.sp
-\fBint start_color(void);\fR
+\fBint start_color(void);\fP
.sp
-\fBbool has_colors(void);\fR
+\fBbool has_colors(void);\fP
.br
-\fBbool can_change_color(void);\fR
+\fBbool can_change_color(void);\fP
.sp
-\fBint init_pair(short \fP\fIpair\fP\fB, short \fP\fIf\fP\fB, short \fP\fIb\fP\fB);\fR
+\fBint init_pair(short \fP\fIpair\fP\fB, short \fP\fIf\fP\fB, short \fP\fIb\fP\fB);\fP
.br
-\fBint init_color(short \fP\fIcolor\fP\fB, short \fP\fIr\fP\fB, short \fP\fIg\fP\fB, short \fP\fIb\fP\fB);\fR
+\fBint init_color(short \fP\fIcolor\fP\fB, short \fP\fIr\fP\fB, short \fP\fIg\fP\fB, short \fP\fIb\fP\fB);\fP
.br
/* extensions */
.br
-\fBint init_extended_pair(int \fP\fIpair\fP\fB, int \fP\fIf\fP\fB, int \fP\fIb\fP\fB);\fR
+\fBint init_extended_pair(int \fP\fIpair\fP\fB, int \fP\fIf\fP\fB, int \fP\fIb\fP\fB);\fP
.br
-\fBint init_extended_color(int \fP\fIcolor\fP\fB, int \fP\fIr\fP\fB, int \fP\fIg\fP\fB, int \fP\fIb\fP\fB);\fR
+\fBint init_extended_color(int \fP\fIcolor\fP\fB, int \fP\fIr\fP\fB, int \fP\fIg\fP\fB, int \fP\fIb\fP\fB);\fP
.sp
-\fBint color_content(short \fP\fIcolor\fP\fB, short *\fP\fIr\fP\fB, short *\fP\fIg\fP\fB, short *\fP\fIb\fP\fB);\fR
+\fBint color_content(short \fP\fIcolor\fP\fB, short *\fP\fIr\fP\fB, short *\fP\fIg\fP\fB, short *\fP\fIb\fP\fB);\fP
.br
-\fBint pair_content(short \fP\fIpair\fP\fB, short *\fP\fIf\fP\fB, short *\fP\fIb\fP\fB);\fR
+\fBint pair_content(short \fP\fIpair\fP\fB, short *\fP\fIf\fP\fB, short *\fP\fIb\fP\fB);\fP
.br
/* extensions */
.br
-\fBint extended_color_content(int \fP\fIcolor\fP\fB, int *\fP\fIr\fP\fB, int *\fP\fIg\fP\fB, int *\fP\fIb\fP\fB);\fR
+\fBint extended_color_content(int \fP\fIcolor\fP\fB, int *\fP\fIr\fP\fB, int *\fP\fIg\fP\fB, int *\fP\fIb\fP\fB);\fP
.br
-\fBint extended_pair_content(int \fP\fIpair\fP\fB, int *\fP\fIf\fP\fB, int *\fP\fIb\fP\fB);\fR
+\fBint extended_pair_content(int \fP\fIpair\fP\fB, int *\fP\fIf\fP\fB, int *\fP\fIb\fP\fB);\fP
.sp
/* extensions */
.br
-\fBvoid reset_color_pairs(void);\fR
+\fBvoid reset_color_pairs(void);\fP
.sp
-\fBint COLOR_PAIR(int \fP\fIn\fP\fB);\fR
+\fBint COLOR_PAIR(int \fP\fIn\fP\fB);\fP
.br
-\fBPAIR_NUMBER(\fR\fIattrs\fR\fB);\fP
+\fBPAIR_NUMBER(\fP\fIattrs\fP\fB);\fP
.br
.SH DESCRIPTION
.SS Overview
-\fBcurses\fR supports color attributes on terminals with that capability.
-To use these routines \fBstart_color\fR must be called, usually right after
-\fBinitscr\fR.
+\fBcurses\fP supports color attributes on terminals with that capability.
+To use these routines \fBstart_color\fP must be called, usually right after
+\fBinitscr\fP.
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 displayed).
-A programmer initializes a color-pair with the routine \fBinit_pair\fR.
-After it has been initialized, \fBCOLOR_PAIR\fR(\fIn\fR)
+A programmer initializes a color-pair with the routine \fBinit_pair\fP.
+After it has been initialized, \fBCOLOR_PAIR\fP(\fIn\fP)
can be used to convert the pair to a 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\fP to change the definition of a color.
+The routines \fBhas_colors\fP and \fBcan_change_color\fP
+return \fBTRUE\fP or \fBFALSE\fP,
depending on whether the terminal has color capabilities and whether the
programmer can change the colors.
-The routine \fBcolor_content\fR allows a
+The routine \fBcolor_content\fP allows a
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
+The routine \fBpair_content\fP allows a programmer to find
out how a given color-pair is currently defined.
.SS Color Rendering
The \fBcurses\fP library combines these inputs to produce the
the background character.
.SH CONSTANTS
.PP
-In \fB<curses.h>\fR the following macros are defined.
+In \fB<curses.h>\fP the following macros are defined.
These are the standard colors (ISO-6429).
-\fBcurses\fR also assumes that \fBCOLOR_BLACK\fR is the default
+\fBcurses\fP also assumes that \fBCOLOR_BLACK\fP is the default
background color for all terminals.
.PP
.nf
- \fBCOLOR_BLACK\fR
- \fBCOLOR_RED\fR
- \fBCOLOR_GREEN\fR
- \fBCOLOR_YELLOW\fR
- \fBCOLOR_BLUE\fR
- \fBCOLOR_MAGENTA\fR
- \fBCOLOR_CYAN\fR
- \fBCOLOR_WHITE\fR
+ \fBCOLOR_BLACK\fP
+ \fBCOLOR_RED\fP
+ \fBCOLOR_GREEN\fP
+ \fBCOLOR_YELLOW\fP
+ \fBCOLOR_BLUE\fP
+ \fBCOLOR_MAGENTA\fP
+ \fBCOLOR_CYAN\fP
+ \fBCOLOR_WHITE\fP
.fi
.PP
Some terminals support more than the eight (8) \*(``ANSI\*('' colors.
the terminal can support.
.SH FUNCTIONS
.SS start_color
-The \fBstart_color\fR routine requires no arguments.
+The \fBstart_color\fP 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:
+It is good practice to call this routine right after \fBinitscr\fP.
+\fBstart_color\fP does this:
.bP
-It initializes two global variables, \fBCOLORS\fR and
-\fBCOLOR_PAIRS\fR (respectively defining the maximum number of colors
+It initializes two global variables, \fBCOLORS\fP and
+\fBCOLOR_PAIRS\fP (respectively defining the maximum number of colors
and color-pairs the terminal can support).
.bP
It initializes the special color pair \fB0\fP to the default foreground
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\fR capability,
-(see \fBterminfo\fR(\*n)).
+\fBCOLORS\fP corresponds to the terminal database's \fBmax_colors\fP capability,
+(see \fBterminfo\fP(\*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
\fBCOLOR_PAIRS\fP corresponds to
the terminal database's \fBmax_pairs\fP capability,
-(see \fBterminfo\fR(\*n)).
+(see \fBterminfo\fP(\*n)).
.bP
legal color pair values are in the range \fB1\fP to \fBCOLOR_PAIRS\-1\fP,
inclusive.
It cannot be modified by the application.
.SS has_colors
.PP
-The \fBhas_colors\fR routine requires no arguments.
-It returns \fBTRUE\fR if
-the terminal can manipulate colors; otherwise, it returns \fBFALSE\fR.
+The \fBhas_colors\fP routine requires no arguments.
+It returns \fBTRUE\fP if
+the terminal can manipulate colors; otherwise, it returns \fBFALSE\fP.
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.
.SS can_change_color
.PP
-The \fBcan_change_color\fR routine requires no arguments.
-It returns \fBTRUE\fR if the terminal supports colors
+The \fBcan_change_color\fP routine requires no arguments.
+It returns \fBTRUE\fP if the terminal supports colors
and can change their definitions;
-other, it returns \fBFALSE\fR.
+other, it returns \fBFALSE\fP.
This routine facilitates writing terminal-independent programs.
.SS init_pair
.PP
-The \fBinit_pair\fR routine changes the definition of a color-pair.
+The \fBinit_pair\fP 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.
are changed to the new definition.
.PP
As an extension, ncurses allows you to set color pair \fB0\fP via
-the \fBassume_default_colors\fR(3X) routine, or to specify the use of
-default colors (color number \fB\-1\fR) if you first invoke the
-\fBuse_default_colors\fR(3X) routine.
+the \fBassume_default_colors\fP(3X) routine, or to specify the use of
+default colors (color number \fB\-1\fP) if you first invoke the
+\fBuse_default_colors\fP(3X) routine.
.SS init_extended_pair
.PP
Because \fBinit_pair\fP uses signed \fBshort\fPs for its parameters,
allowing a larger number of colors to be supported.
.SS init_color
.PP
-The \fBinit_color\fR routine changes the definition of a color.
+The \fBinit_color\fP 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).
.bP
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.)
+(See the section \fBColors\fP for the default color index.)
.bP
Each of the last three arguments
must be a value in the range \fB0\fP through \fB1000\fP.
.PP
-When \fBinit_color\fR is used, all
+When \fBinit_color\fP is used, all
occurrences of that color on the screen immediately change to the new
definition.
.SS init_extended_color
allowing a larger number of colors to be supported.
.SS color_content
.PP
-The \fBcolor_content\fR routine gives programmers a way to find the intensity
+The \fBcolor_content\fP 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
allowing a larger number of colors to be supported.
.SS pair_content
.PP
-The \fBpair_content\fR routine allows programmers to find out what colors a
+The \fBpair_content\fP 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 \fBshort\fRs for storing the foreground and the
background color numbers.
.bP
The first argument must be a legal color value,
-i.e., in the range \fB1\fP through \fBCOLOR_PAIRS\-1\fR, inclusive.
+i.e., in the range \fB1\fP through \fBCOLOR_PAIRS\-1\fP, inclusive.
.bP
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.
+range \fB0\fP through \fBCOLORS\fP, inclusive.
.SS extended_pair_content
.PP
Because \fBpair_content\fP uses signed \fBshort\fPs for its parameters,
switch color palettes rapidly.
.SS PAIR_NUMBER
.PP
-\fBPAIR_NUMBER(\fR\fIattrs\fR) extracts the color
+\fBPAIR_NUMBER(\fP\fIattrs\fP) extracts the color
value from its \fIattrs\fP parameter and returns it as a color pair number.
.SS COLOR_PAIR
-Its inverse \fBCOLOR_PAIR(\fR\fIn\fR\fB)\fR converts a color pair number
+Its inverse \fBCOLOR_PAIR(\fP\fIn\fP\fB)\fP 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 \fBattr_set\fP (which pass the color pair as a separate parameter)
rather than the legacy functions such as \fBattrset\fP.
.SH RETURN VALUE
-The routines \fBcan_change_color\fR and \fBhas_colors\fR return \fBTRUE\fR
-or \fBFALSE\fR.
+The routines \fBcan_change_color\fP and \fBhas_colors\fP return \fBTRUE\fP
+or \fBFALSE\fP.
.PP
-All other routines return the integer \fBERR\fR upon failure and an \fBOK\fR
+All other routines return the integer \fBERR\fP upon failure and an \fBOK\fP
(SVr4 specifies only \*(``an integer value
-other than \fBERR\fR\*('') upon successful completion.
+other than \fBERR\fP\*('') upon successful completion.
.PP
X/Open defines no error conditions.
SVr4 does document some error conditions which apply in general:
.bP
-This implementation will return \fBERR\fR on attempts to
+This implementation will return \fBERR\fP on attempts to
use color values outside the range \fB0\fP to \fBCOLORS\fP\-1
(except for the default colors extension),
or use color pairs outside the range \fB0\fP to \fBCOLOR_PAIRS\-1\fP.
returns an error if the color table cannot be allocated.
.RE
.SH NOTES
-In the \fBncurses\fR implementation, there is a separate color activation flag,
+In the \fBncurses\fP implementation, there is a separate color activation flag,
color palette, color pairs table,
and associated \fBCOLORS\fP and \fBCOLOR_PAIRS\fP counts
-for each screen; the \fBstart_color\fR function only affects the current
+for each screen; the \fBstart_color\fP 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.
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).
+scrolling operations, see \fBcurs_bkgd\fP(3X).
.PP
Several caveats apply on older x86 machines
(e.g., i386, i486) with VGA-compatible graphics:
.bP
COLOR_YELLOW is actually brown.
-To get yellow, use COLOR_YELLOW combined with the \fBA_BOLD\fR attribute.
+To get yellow, use COLOR_YELLOW combined with the \fBA_BOLD\fP 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
by the size of the bitfield.
.SH PORTABILITY
This implementation satisfies XSI Curses's minimum maximums
-for \fBCOLORS\fR and \fBCOLOR_PAIRS\fR.
+for \fBCOLORS\fP and \fBCOLOR_PAIRS\fP.
.PP
The \fBinit_pair\fP routine accepts negative values of foreground
-and background color to support the \fBuse_default_colors\fR(3X) extension,
+and background color to support the \fBuse_default_colors\fP(3X) extension,
but only if that routine has been first invoked.
.PP
-The assumption that \fBCOLOR_BLACK\fR is the default
+The assumption that \fBCOLOR_BLACK\fP is the default
background color for all terminals can be modified using the
-\fBassume_default_colors\fR(3X) extension.
+\fBassume_default_colors\fP(3X) extension.
.PP
This implementation checks the pointers,
e.g., for the values returned by
.PP
The \fBreset_color_pairs\fP function is an extension of ncurses.
.SH SEE ALSO
-\fBcurses\fR(3X),
-\fBcurs_initscr\fR(3X),
-\fBcurs_attr\fR(3X),
-\fBcurs_variables\fR(3X),
-\fBdefault_colors\fR(3X)
+\fBcurses\fP(3X),
+\fBcurs_initscr\fP(3X),
+\fBcurs_attr\fP(3X),
+\fBcurs_variables\fP(3X),
+\fBdefault_colors\fP(3X)
projects / ncurses.git / blobdiff