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Term::ANSIColor(3Perl Programmers Reference GuTerm::ANSIColor(3p)


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.\n", 'yellow on_magenta');
           print "This text is normal.\n";
           print colored ['yellow on_magenta'], "Yellow on magenta.\n";

           use Term::ANSIColor qw(uncolor);
           print uncolor '01;31', "\n";

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

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

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

       color() takes any number of strings as arguments and con-
       siders 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).

       uncolor() performs the opposite translation, turning
       escape sequences into a list of strings.

       The recognized attributes (all of which should be fairly
       intuitive) are clear, reset, dark, bold, underline, under-
       score, blink, reverse, concealed, black, red, green, yel-
       low, blue, magenta, on_black, on_red, on_green, on_yellow,
       on_blue, on_magenta, on_cyan, and on_white.  Case is not
       significant.  Underline and underscore are equivalent, as
       are clear and reset, so use whichever is the most intu-
       itive to you.  The color alone sets the foreground color,
       and on_color sets the background color.

       Note that not all attributes are supported by all terminal



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       types, and some terminals may not support any of these
       sequences.  Dark, blink, and concealed in particular are
       frequently not implemented.

       Attributes, once set, last until they are unset (by send-
       ing the attribute "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.

       As an aid to help with this, 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 is being sent to a program like a
       pager that can be confused by attributes that span lines.
       Normally you'll want to set $Term::ANSIColor::EACHLINE to
       "\n" to use this feature.

       Alternately, if you import ":constants", you can use the
       constants CLEAR, RESET, BOLD, DARK, UNDERLINE, UNDERSCORE,
       BLINK, REVERSE, CONCEALED, BLACK, RED, GREEN, YELLOW,
       BLUE, MAGENTA, CYAN, WHITE, ON_BLACK, ON_RED, ON_GREEN,
       ON_YELLOW, ON_BLUE, ON_MAGENTA, ON_CYAN, and ON_WHITE
       directly.  These are the same as color('attribute') and
       can be used if you prefer typing:

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

       to

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

       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";




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       will reset the display mode afterwards, whereas:

           print BOLD, BLUE, "Text\n";

       will not.

       The subroutine interface has the advantage over the con-
       stants interface in that only two subroutines are exported
       into your namespace, versus twenty-two in the constants
       interface.  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, polute 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.

DIAGNOSTICS
       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).

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

       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 con-
           stant names in order to force the next error.

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




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               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() con-
           tains escapes which aren't recognized and can't be
           translated to names.

ENVIRONMENT
       ANSI_COLORS_DISABLED
           If this environment variable is set, all of the func-
           tions defined by this module (color(), colored(), and
           all of the constants not previously used in the pro-
           gram) 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 plat-
           forms that don't support ANSI escape sequences.

           For it to have its proper effect, this environment
           variable must be set before any color constants are
           used in the program.

RESTRICTIONS
       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.)

       For easier debuging, you may prefer to always use the com-
       mas when not setting $Term::ANSIColor::AUTORESET so that
       you'll get a fatal compile error rather than a warning.

NOTES
       The codes generated by this module are standard terminal
       control codes, complying with ECMA-48 and ISO 6429 (gener-
       ally referred to as "ANSI color" for the color codes).
       The non-color control codes (bold, dark, italic, under-
       line, 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



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       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 vari-
       ous attributes and others have helped me flesh it out:

                     clear    bold     dark    under    blink   reverse  conceal
        ------------------------------------------------------------------------
        xterm         yes      yes      no      yes     bold      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

       Windows is Windows telnet, and Cygwin SSH is the OpenSSH
       implementation under Cygwin on Windows NT.  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.

       Note that codes 3 (italic), 6 (rapid blink), and 9
       (strikethrough) are specified in ANSI X3.64 and ECMA-048
       but are not commonly supported by most displays and emula-
       tors and therefore aren't supported by this module at the
       present time.  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.

SEE ALSO
       ECMA-048 is available on-line (at least at the time of
       this writing) at <http://www.ecma-international.org/publi-
       cations/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 current version of this module is always available
       from its web site at <http://www.eyrie.org/~eagle/soft-
       ware/ansicolor/>.  It is also part of the Perl core



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       distribution as of 5.6.0.

AUTHORS
       Original idea (using constants) by Zenin, reimplemented
       using subs by Russ Allbery <rraATstanford.edu>, and then
       combined with the original idea by Russ with input from
       Zenin.  Russ Allbery now maintains this module.

COPYRIGHT AND LICENSE
       Copyright 1996, 1997, 1998, 2000, 2001, 2002 Russ Allbery
       <rraATstanford.edu> and Zenin <zeninATbawdycaste.org>.  This
       program is free software; you may redistribute it and/or
       modify it under the same terms as Perl itself.












































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