Term::ANSIColor - man - phpman

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NAME
Term::ANSIColor - Color screen output using ANSI escape sequences

SYNOPSIS
use Term::ANSIColor;
print color('bold blue');
print "This text is bold blue.\n";
print color('reset');
print "This text is normal.\n";
print colored("Yellow on magenta.", 'yellow on_magenta'), "\n";
print "This text is normal.\n";
print colored(['yellow on_magenta'], 'Yellow on magenta.', "\n");
print colored(['red on_bright_yellow'], 'Red on bright yellow.', "\n");
print colored(['bright_red on_black'], 'Bright red on black.', "\n");
print "\n";

# Map escape sequences back to color names.
use Term::ANSIColor 1.04 qw(uncolor);
my @names = uncolor('01;31');
print join(q{ }, @names), "\n";

# Strip all color escape sequences.
use Term::ANSIColor 2.01 qw(colorstrip);
print colorstrip("\e[1mThis is bold\e[0m"), "\n";

# Determine whether a color is valid.
use Term::ANSIColor 2.02 qw(colorvalid);
my $valid = colorvalid('blue bold', 'on_magenta');
print "Color string is ", $valid ? "valid\n" : "invalid\n";

# Create new aliases for colors.
use Term::ANSIColor 4.00 qw(coloralias);
coloralias('alert', 'red');
print "Alert is ", coloralias('alert'), "\n";
print colored("This is in red.", 'alert'), "\n";

use Term::ANSIColor qw(:constants);
print BOLD, BLUE, "This text is in bold blue.\n", RESET;

use Term::ANSIColor qw(:constants);
{
local $Term::ANSIColor::AUTORESET = 1;
print BOLD BLUE "This text is in bold blue.\n";
print "This text is normal.\n";
}

use Term::ANSIColor 2.00 qw(:pushpop);
print PUSHCOLOR RED ON_GREEN "This text is red on green.\n";
print PUSHCOLOR BRIGHT_BLUE "This text is bright blue on green.\n";
print RESET BRIGHT_BLUE "This text is just bright blue.\n";
print POPCOLOR "Back to red on green.\n";
print LOCALCOLOR GREEN ON_BLUE "This text is green on blue.\n";
print "This text is red on green.\n";
{
local $Term::ANSIColor::AUTOLOCAL = 1;
print ON_BLUE "This text is red on blue.\n";
print "This text is red on green.\n";
}
print POPCOLOR "Back to whatever we started as.\n";

DESCRIPTION
This module has two interfaces, one through color() and colored() and the other through
constants. It also offers the utility functions uncolor(), colorstrip(), colorvalid(), and
coloralias(), which have to be explicitly imported to be used (see "SYNOPSIS").

If you are using Term::ANSIColor in a console command, consider supporting the CLICOLOR
standard. See "Supporting CLICOLOR" for more information.

See "COMPATIBILITY" for the versions of Term::ANSIColor that introduced particular features and
the versions of Perl that included them.

Supported Colors
Terminal emulators that support color divide into four types: ones that support only eight
colors, ones that support sixteen, ones that support 256, and ones that support 24-bit color.
This module provides the ANSI escape codes for all of them. These colors are referred to as ANSI
colors 0 through 7 (normal), 8 through 15 (16-color), 16 through 255 (256-color), and true color
(called direct-color by xterm).

Unfortunately, interpretation of colors 0 through 7 often depends on whether the emulator
supports eight colors or sixteen colors. Emulators that only support eight colors (such as the
Linux console) will display colors 0 through 7 with normal brightness and ignore colors 8
through 15, treating them the same as white. Emulators that support 16 colors, such as
gnome-terminal, normally display colors 0 through 7 as dim or darker versions and colors 8
through 15 as normal brightness. On such emulators, the "normal" white (color 7) usually is
shown as pale grey, requiring bright white (15) to be used to get a real white color. Bright
black usually is a dark grey color, although some terminals display it as pure black. Some
sixteen-color terminal emulators also treat normal yellow (color 3) as orange or brown, and
bright yellow (color 11) as yellow.

Following the normal convention of sixteen-color emulators, this module provides a pair of
attributes for each color. For every normal color (0 through 7), the corresponding bright color
(8 through 15) is obtained by prepending the string "bright_" to the normal color name. For
example, "red" is color 1 and "bright_red" is color 9. The same applies for background colors:
"on_red" is the normal color and "on_bright_red" is the bright color. Capitalize these strings
for the constant interface.

There is unfortunately no way to know whether the current emulator supports more than eight
colors, which makes the choice of colors difficult. The most conservative choice is to use only
the regular colors, which are at least displayed on all emulators. However, they will appear
dark in sixteen-color terminal emulators, including most common emulators in UNIX X
environments. If you know the display is one of those emulators, you may wish to use the bright
variants instead. Even better, offer the user a way to configure the colors for a given
application to fit their terminal emulator.

For 256-color emulators, this module additionally provides "ansi0" through "ansi15", which are
the same as colors 0 through 15 in sixteen-color emulators but use the 256-color escape syntax,
"grey0" through "grey23" ranging from nearly black to nearly white, and a set of RGB colors. The
RGB colors are of the form "rgb*RGB*" where *R*, *G*, and *B* are numbers from 0 to 5 giving the
intensity of red, green, and blue. The grey and RGB colors are also available as "ansi16"
through "ansi255" if you want simple names for all 256 colors. "on_" variants of all of these
colors are also provided. These colors may be ignored completely on non-256-color terminals or
may be misinterpreted and produce random behavior. Additional attributes such as blink, italic,
or bold may not work with the 256-color palette.

For true color emulators, this module supports attributes of the form "r*NNN*g*NNN*b*NNN*" and
"on_r*NNN*g*NNN*b*NNN*" for all values of *NNN* between 0 and 255. These represent foreground
and background colors, respectively, with the RGB values given by the *NNN* numbers. These
colors may be ignored completely on non-true-color terminals or may be misinterpreted and
produce random behavior.

Function Interface
The function interface uses attribute strings to describe the colors and text attributes to
assign to text. The recognized non-color attributes are clear, reset, bold, dark, faint, italic,
underline, underscore, blink, reverse, and concealed. Clear and reset (reset to default
attributes), dark and faint (dim and saturated), and underline and underscore are equivalent, so
use whichever is the most intuitive to you.

Note that not all attributes are supported by all terminal types, and some terminals may not
support any of these sequences. Dark and faint, italic, blink, and concealed in particular are
frequently not implemented.

The recognized normal foreground color attributes (colors 0 to 7) are:

black red green yellow blue magenta cyan white

The corresponding bright foreground color attributes (colors 8 to 15) are:

bright_black bright_red bright_green bright_yellow
bright_blue bright_magenta bright_cyan bright_white

The recognized normal background color attributes (colors 0 to 7) are:

on_black on_red on_green on yellow
on_blue on_magenta on_cyan on_white

The recognized bright background color attributes (colors 8 to 15) are:

on_bright_black on_bright_red on_bright_green on_bright_yellow
on_bright_blue on_bright_magenta on_bright_cyan on_bright_white

For 256-color terminals, the recognized foreground colors are:

ansi0 .. ansi255
grey0 .. grey23

plus "rgb*RGB*" for *R*, *G*, and *B* values from 0 to 5, such as "rgb000" or "rgb515".
Similarly, the recognized background colors are:

on_ansi0 .. on_ansi255
on_grey0 .. on_grey23

plus "on_rgb*RGB*" for *R*, *G*, and *B* values from 0 to 5.

For true color terminals, the recognized foreground colors are "r*RRR*g*GGG*b*BBB*" for *RRR*,
*GGG*, and *BBB* values between 0 and 255. Similarly, the recognized background colors are
"on_r*RRR*g*GGG*b*BBB*" for *RRR*, *GGG*, and *BBB* values between 0 and 255.

For any of the above listed attributes, case is not significant.

Attributes, once set, last until they are unset (by printing the attribute "clear" or "reset").
Be careful to do this, or otherwise your attribute will last after your script is done running,
and people get very annoyed at having their prompt and typing changed to weird colors.

color(ATTR[, ATTR ...])
color() takes any number of strings as arguments and considers them to be space-separated
lists of attributes. It then forms and returns the escape sequence to set those attributes.
It doesn't print it out, just returns it, so you'll have to print it yourself if you want
to. This is so that you can save it as a string, pass it to something else, send it to a
file handle, or do anything else with it that you might care to. color() throws an exception
if given an invalid attribute.

colored(STRING, ATTR[, ATTR ...])
colored(ATTR-REF, STRING[, STRING...])
As an aid in resetting colors, colored() takes a scalar as the first argument and any number
of attribute strings as the second argument and returns the scalar wrapped in escape codes
so that the attributes will be set as requested before the string and reset to normal after
the string. Alternately, you can pass a reference to an array as the first argument, and
then the contents of that array will be taken as attributes and color codes and the
remainder of the arguments as text to colorize.

Normally, colored() just puts attribute codes at the beginning and end of the string, but if
you set $Term::ANSIColor::EACHLINE to some string, that string will be considered the line
delimiter and the attribute will be set at the beginning of each line of the passed string
and reset at the end of each line. This is often desirable if the output contains newlines
and you're using background colors, since a background color that persists across a newline
is often interpreted by the terminal as providing the default background color for the next
line. Programs like pagers can also be confused by attributes that span lines. Normally
you'll want to set $Term::ANSIColor::EACHLINE to "\n" to use this feature.

Particularly consider setting $Term::ANSIColor::EACHLINE if you are interleaving output to
standard output and standard error and you aren't flushing standard output (via autoflush()
or setting $|). If you don't, the code to reset the color may unexpectedly sit in the
standard output buffer rather than going to the display, causing standard error output to
appear in the wrong color.

uncolor(ESCAPE)
uncolor() performs the opposite translation as color(), turning escape sequences into a list
of strings corresponding to the attributes being set by those sequences. uncolor() will
never return "ansi16" through "ansi255", instead preferring the "grey" and "rgb" names (and
likewise for "on_ansi16" through "on_ansi255").

colorstrip(STRING[, STRING ...])
colorstrip() removes all color escape sequences from the provided strings, returning the
modified strings separately in array context or joined together in scalar context. Its
arguments are not modified.

colorvalid(ATTR[, ATTR ...])
colorvalid() takes attribute strings the same as color() and returns true if all attributes
are known and false otherwise.

coloralias(ALIAS[, ATTR ...])
If ATTR is specified, it is interpreted as a list of space-separated strings naming
attributes or existing aliases. In this case, coloralias() sets up an alias of ALIAS for the
set of attributes given by ATTR. From that point forward, ALIAS can be passed into color(),
colored(), and colorvalid() and will have the same meaning as the sequence of attributes
given in ATTR. One possible use of this facility is to give more meaningful names to the
256-color RGB colors. Only ASCII alphanumerics, ".", "_", and "-" are allowed in alias
names.

If ATTR includes aliases, those aliases will be expanded at definition time and their values
will be used to define the new alias. This means that if you define an alias A in terms of
another alias B, and then later redefine alias B, the value of alias A will not change.

If ATTR is not specified, coloralias() returns the standard attribute or attributes to which
ALIAS is aliased, if any, or undef if ALIAS does not exist. If it is aliased to multiple
attributes, the return value will be a single string and the attributes will be separated by
spaces.

This is the same facility used by the ANSI_COLORS_ALIASES environment variable (see
"ENVIRONMENT" below) but can be used at runtime, not just when the module is loaded.

Later invocations of coloralias() with the same ALIAS will override earlier aliases. There
is no way to remove an alias.

Aliases have no effect on the return value of uncolor().

WARNING: Aliases are global and affect all callers in the same process. There is no way to
set an alias limited to a particular block of code or a particular object.

Constant Interface
Alternately, if you import ":constants", you can use the following constants directly:

CLEAR RESET BOLD DARK
FAINT ITALIC UNDERLINE UNDERSCORE
BLINK REVERSE CONCEALED

BLACK RED GREEN YELLOW
BLUE MAGENTA CYAN WHITE
BRIGHT_BLACK BRIGHT_RED BRIGHT_GREEN BRIGHT_YELLOW
BRIGHT_BLUE BRIGHT_MAGENTA BRIGHT_CYAN BRIGHT_WHITE

ON_BLACK ON_RED ON_GREEN ON_YELLOW
ON_BLUE ON_MAGENTA ON_CYAN ON_WHITE
ON_BRIGHT_BLACK ON_BRIGHT_RED ON_BRIGHT_GREEN ON_BRIGHT_YELLOW
ON_BRIGHT_BLUE ON_BRIGHT_MAGENTA ON_BRIGHT_CYAN ON_BRIGHT_WHITE

These are the same as color('attribute') and can be used if you prefer typing:

print BOLD BLUE ON_WHITE "Text", RESET, "\n";

print colored ("Text", 'bold blue on_white'), "\n";

(Note that the newline is kept separate to avoid confusing the terminal as described above since
a background color is being used.)

If you import ":constants256", you can use the following constants directly:

ANSI0 .. ANSI255
GREY0 .. GREY23

RGBXYZ (for X, Y, and Z values from 0 to 5, like RGB000 or RGB515)

ON_ANSI0 .. ON_ANSI255
ON_GREY0 .. ON_GREY23

ON_RGBXYZ (for X, Y, and Z values from 0 to 5)

Note that ":constants256" does not include the other constants, so if you want to mix both, you
need to include ":constants" as well. You may want to explicitly import at least "RESET", as in:

use Term::ANSIColor 4.00 qw(RESET :constants256);

True color and aliases are not supported by the constant interface.

When using the constants, if you don't want to have to remember to add the ", RESET" at the end
of each print line, you can set $Term::ANSIColor::AUTORESET to a true value. Then, the display
mode will automatically be reset if there is no comma after the constant. In other words, with
that variable set:

print BOLD BLUE "Text\n";

will reset the display mode afterward, whereas:

print BOLD, BLUE, "Text\n";

will not. If you are using background colors, you will probably want to either use say() (in
newer versions of Perl) or print the newline with a separate print statement to avoid confusing
the terminal.

If $Term::ANSIColor::AUTOLOCAL is set (see below), it takes precedence over
$Term::ANSIColor::AUTORESET, and the latter is ignored.

The subroutine interface has the advantage over the constants interface in that only two
subroutines are exported into your namespace, versus thirty-eight in the constants interface,
and aliases and true color attributes are supported. On the flip side, the constants interface
has the advantage of better compile time error checking, since misspelled names of colors or
attributes in calls to color() and colored() won't be caught until runtime whereas misspelled
names of constants will be caught at compile time. So, pollute your namespace with almost two
dozen subroutines that you may not even use that often, or risk a silly bug by mistyping an
attribute. Your choice, TMTOWTDI after all.

The Color Stack
You can import ":pushpop" and maintain a stack of colors using PUSHCOLOR, POPCOLOR, and
LOCALCOLOR. PUSHCOLOR takes the attribute string that starts its argument and pushes it onto a
stack of attributes. POPCOLOR removes the top of the stack and restores the previous attributes
set by the argument of a prior PUSHCOLOR. LOCALCOLOR surrounds its argument in a PUSHCOLOR and
POPCOLOR so that the color resets afterward.

If $Term::ANSIColor::AUTOLOCAL is set, each sequence of color constants will be implicitly
preceded by LOCALCOLOR. In other words, the following:

{
local $Term::ANSIColor::AUTOLOCAL = 1;
print BLUE "Text\n";
}

is equivalent to:

print LOCALCOLOR BLUE "Text\n";

If $Term::ANSIColor::AUTOLOCAL is set, it takes precedence over $Term::ANSIColor::AUTORESET, and
the latter is ignored.

When using PUSHCOLOR, POPCOLOR, and LOCALCOLOR, it's particularly important to not put commas
between the constants.

print PUSHCOLOR BLUE "Text\n";

will correctly push BLUE onto the top of the stack.

print PUSHCOLOR, BLUE, "Text\n"; # wrong!

will not, and a subsequent pop won't restore the correct attributes. PUSHCOLOR pushes the
attributes set by its argument, which is normally a string of color constants. It can't ask the
terminal what the current attributes are.

Supporting CLICOLOR
<https://bixense.com/clicolors/> proposes a standard for enabling and disabling color output
from console commands using two environment variables, CLICOLOR and CLICOLOR_FORCE.
Term::ANSIColor cannot automatically support this standard, since the correct action depends on
where the output is going and Term::ANSIColor may be used in a context where colors should
always be generated even if CLICOLOR is set in the environment. But you can use the supported
environment variable ANSI_COLORS_DISABLED to implement CLICOLOR in your own programs with code
like this:

if (exists($ENV{CLICOLOR}) && $ENV{CLICOLOR} == 0) {
if (!$ENV{CLICOLOR_FORCE}) {
$ENV{ANSI_COLORS_DISABLED} = 1;
}
}

If you are using the constant interface, be sure to include this code before you use any color
constants (such as at the very top of your script), since this environment variable is only
honored the first time a color constant is seen.

Be aware that this will export ANSI_COLORS_DISABLED to any child processes of your program as
well.

DIAGNOSTICS
Bad color mapping %s
(W) The specified color mapping from ANSI_COLORS_ALIASES is not valid and could not be
parsed. It was ignored.

Bad escape sequence %s
(F) You passed an invalid ANSI escape sequence to uncolor().

Bareword "%s" not allowed while "strict subs" in use
(F) You probably mistyped a constant color name such as:

$Foobar = FOOBAR . "This line should be blue\n";

or:

@Foobar = FOOBAR, "This line should be blue\n";

This will only show up under use strict (another good reason to run under use strict).

Cannot alias standard color %s
(F) The alias name passed to coloralias() matches a standard color name. Standard color
names cannot be aliased.

Cannot alias standard color %s in %s
(W) The same, but in ANSI_COLORS_ALIASES. The color mapping was ignored.

Invalid alias name %s
(F) You passed an invalid alias name to coloralias(). Alias names must consist only of
alphanumerics, ".", "-", and "_".

Invalid alias name %s in %s
(W) You specified an invalid alias name on the left hand of the equal sign in a color
mapping in ANSI_COLORS_ALIASES. The color mapping was ignored.

Invalid attribute name %s
(F) You passed an invalid attribute name to color(), colored(), or coloralias().

Invalid attribute name %s in %s
(W) You specified an invalid attribute name on the right hand of the equal sign in a color
mapping in ANSI_COLORS_ALIASES. The color mapping was ignored.

Name "%s" used only once: possible typo
(W) You probably mistyped a constant color name such as:

print FOOBAR "This text is color FOOBAR\n";

It's probably better to always use commas after constant names in order to force the next
error.

No comma allowed after filehandle
(F) You probably mistyped a constant color name such as:

print FOOBAR, "This text is color FOOBAR\n";

Generating this fatal compile error is one of the main advantages of using the constants
interface, since you'll immediately know if you mistype a color name.

No name for escape sequence %s
(F) The ANSI escape sequence passed to uncolor() contains escapes which aren't recognized
and can't be translated to names.

ENVIRONMENT
ANSI_COLORS_ALIASES
This environment variable allows the user to specify custom color aliases that will be
understood by color(), colored(), and colorvalid(). None of the other functions will be
affected, and no new color constants will be created. The custom colors are aliases for
existing color names; no new escape sequences can be introduced. Only alphanumerics, ".",
"_", and "-" are allowed in alias names.

The format is:

ANSI_COLORS_ALIASES='newcolor1=oldcolor1,newcolor2=oldcolor2'

Whitespace is ignored. The alias value can be a single attribute or a space-separated list
of attributes.

For example the Solarized <https://ethanschoonover.com/solarized> colors can be mapped with:

ANSI_COLORS_ALIASES='\
base00=bright_yellow, on_base00=on_bright_yellow,\
base01=bright_green, on_base01=on_bright_green, \
base02=black, on_base02=on_black, \
base03=bright_black, on_base03=on_bright_black, \
base0=bright_blue, on_base0=on_bright_blue, \
base1=bright_cyan, on_base1=on_bright_cyan, \
base2=white, on_base2=on_white, \
base3=bright_white, on_base3=on_bright_white, \
orange=bright_red, on_orange=on_bright_red, \
violet=bright_magenta,on_violet=on_bright_magenta'

This environment variable is read and applied when the Term::ANSIColor module is loaded and
is then subsequently ignored. Changes to ANSI_COLORS_ALIASES after the module is loaded will
have no effect. See coloralias() for an equivalent facility that can be used at runtime.

ANSI_COLORS_DISABLED
If this environment variable is set to a true value, all of the functions defined by this
module (color(), colored(), and all of the constants) will not output any escape sequences
and instead will just return the empty string or pass through the original text as
appropriate. This is intended to support easy use of scripts using this module on platforms
that don't support ANSI escape sequences.

NO_COLOR
If this environment variable is set to any value, it suppresses generation of escape
sequences the same as if ANSI_COLORS_DISABLED is set to a true value. This implements the
<https://no-color.org/> informal standard. Programs that want to enable color despite
NO_COLOR being set will need to unset that environment variable before any constant or
function provided by this module is used.

COMPATIBILITY
Term::ANSIColor was first included with Perl in Perl 5.6.0.

The uncolor() function and support for ANSI_COLORS_DISABLED were added in Term::ANSIColor 1.04,
included in Perl 5.8.0.

Support for dark was added in Term::ANSIColor 1.08, included in Perl 5.8.4.

The color stack, including the ":pushpop" import tag, PUSHCOLOR, POPCOLOR, LOCALCOLOR, and the
$Term::ANSIColor::AUTOLOCAL variable, was added in Term::ANSIColor 2.00, included in Perl
5.10.1.

colorstrip() was added in Term::ANSIColor 2.01 and colorvalid() was added in Term::ANSIColor
2.02, both included in Perl 5.11.0.

Support for colors 8 through 15 (the "bright_" variants) was added in Term::ANSIColor 3.00,
included in Perl 5.13.3.

Support for italic was added in Term::ANSIColor 3.02, included in Perl 5.17.1.

Support for colors 16 through 256 (the "ansi", "rgb", and "grey" colors), the ":constants256"
import tag, the coloralias() function, and support for the ANSI_COLORS_ALIASES environment
variable were added in Term::ANSIColor 4.00, included in Perl 5.17.8.

$Term::ANSIColor::AUTOLOCAL was changed to take precedence over $Term::ANSIColor::AUTORESET,
rather than the other way around, in Term::ANSIColor 4.00, included in Perl 5.17.8.

"ansi16" through "ansi255", as aliases for the "rgb" and "grey" colors, and the corresponding
"on_ansi" names and "ANSI" and "ON_ANSI" constants were added in Term::ANSIColor 4.06, included
in Perl 5.25.7.

Support for true color (the "rNNNgNNNbNNN" and "on_rNNNgNNNbNNN" attributes), defining aliases
in terms of other aliases, and aliases mapping to multiple attributes instead of only a single
attribute was added in Term::ANSIColor 5.00.

Support for NO_COLOR was added in Term::ANSIColor 5.01.

RESTRICTIONS
Both colored() and many uses of the color constants will add the reset escape sequence after a
newline. If a program mixes colored output to standard output with output to standard error,
this can result in the standard error text having the wrong color because the reset escape
sequence hasn't yet been flushed to the display (since standard output to a terminal is
line-buffered by default). To avoid this, either set autoflush() on STDOUT or set
$Term::ANSIColor::EACHLINE to "\n".

It would be nice if one could leave off the commas around the constants entirely and just say:

print BOLD BLUE ON_WHITE "Text\n" RESET;

but the syntax of Perl doesn't allow this. You need a comma after the string. (Of course, you
may consider it a bug that commas between all the constants aren't required, in which case you
may feel free to insert commas unless you're using $Term::ANSIColor::AUTORESET or
PUSHCOLOR/POPCOLOR.)

For easier debugging, you may prefer to always use the commas when not setting
$Term::ANSIColor::AUTORESET or PUSHCOLOR/POPCOLOR so that you'll get a fatal compile error
rather than a warning.

It's not possible to use this module to embed formatting and color attributes using Perl
formats. They replace the escape character with a space (as documented in perlform(1)),
resulting in garbled output from the unrecognized attribute. Even if there were a way around
that problem, the format doesn't know that the non-printing escape sequence is zero-length and
would incorrectly format the output. For formatted output using color or other attributes,
either use sprintf() instead or use formline() and then add the color or other attributes after
formatting and before output.

NOTES
The codes generated by this module are standard terminal control codes, complying with ECMA-048
and ISO 6429 (generally referred to as "ANSI color" for the color codes). The non-color control
codes (bold, dark, italic, underline, and reverse) are part of the earlier ANSI X3.64 standard
for control sequences for video terminals and peripherals.

Note that not all displays are ISO 6429-compliant, or even X3.64-compliant (or are even
attempting to be so). This module will not work as expected on displays that do not honor these
escape sequences, such as cmd.exe, 4nt.exe, and command.com under either Windows NT or Windows
2000. They may just be ignored, or they may display as an ESC character followed by some
apparent garbage.

Jean Delvare provided the following table of different common terminal emulators and their
support for the various attributes and others have helped me flesh it out:

clear bold faint under blink reverse conceal
------------------------------------------------------------------------
xterm yes yes no yes yes yes yes
linux yes yes yes bold yes yes no
rxvt yes yes no yes bold/black yes no
dtterm yes yes yes yes reverse yes yes
teraterm yes reverse no yes rev/red yes no
aixterm kinda normal no yes no yes yes
PuTTY yes color no yes no yes no
Windows yes no no no no yes no
Cygwin SSH yes yes no color color color yes
Terminal.app yes yes no yes yes yes yes

Windows is Windows telnet, Cygwin SSH is the OpenSSH implementation under Cygwin on Windows NT,
and Mac Terminal is the Terminal application in Mac OS X. Where the entry is other than yes or
no, that emulator displays the given attribute as something else instead. Note that on an
aixterm, clear doesn't reset colors; you have to explicitly set the colors back to what you
want. More entries in this table are welcome.

Support for code 3 (italic) is rare and therefore not mentioned in that table. It is not
believed to be fully supported by any of the terminals listed, although it's displayed as green
in the Linux console, but it is reportedly supported by urxvt.

Note that codes 6 (rapid blink) and 9 (strike-through) are specified in ANSI X3.64 and ECMA-048
but are not commonly supported by most displays and emulators and therefore aren't supported by
this module. ECMA-048 also specifies a large number of other attributes, including a sequence of
attributes for font changes, Fraktur characters, double-underlining, framing, circling, and
overlining. As none of these attributes are widely supported or useful, they also aren't
currently supported by this module.

Most modern X terminal emulators support 256 colors. Known to not support those colors are
aterm, rxvt, Terminal.app, and TTY/VC.

For information on true color support in various terminal emulators, see True Colour support
<https://gist.github.com/XVilka/8346728>.

AUTHORS
Original idea (using constants) by Zenin, reimplemented using subs by Russ Allbery
<rra AT cpan.org>, and then combined with the original idea by Russ with input from Zenin.
256-color support is based on work by Kurt Starsinic. Russ Allbery now maintains this module.

PUSHCOLOR, POPCOLOR, and LOCALCOLOR were contributed by openmethods.com voice solutions.

This program is free software; you may redistribute it and/or modify it under the same terms as
Perl itself.

SEE ALSO
The CPAN module Term::ExtendedColor provides a different and more comprehensive interface for
256-color emulators that may be more convenient. The CPAN module Win32::Console::ANSI provides
ANSI color (and other escape sequence) support in the Win32 Console environment. The CPAN module
Term::Chrome provides a different interface using objects and operator overloading.

ECMA-048 is available on-line (at least at the time of this writing) at
<https://www.ecma-international.org/publications/standards/Ecma-048.htm>.

ISO 6429 is available from ISO for a charge; the author of this module does not own a copy of
it. Since the source material for ISO 6429 was ECMA-048 and the latter is available for free,
there seems little reason to obtain the ISO standard.

The 256-color control sequences are documented at
<https://invisible-island.net/xterm/ctlseqs/ctlseqs.html> (search for 256-color).

Information about true color support in various terminal emulators and test programs you can run
to check the true color support in your terminal emulator are available at
<https://gist.github.com/XVilka/8346728>.

CLICOLORS <https://bixense.com/clicolors/> and NO_COLOR <https://no-color.org/> are useful
standards to be aware of, and ideally follow, for any application using color. Term::ANSIColor
complies with the latter.

The current version of this module is always available from its web site at
<https://www.eyrie.org/~eagle/software/ansicolor/>. It is also part of the Perl core
distribution as of 5.6.0.