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RedHat 9 (Linux i386) - man page for term::ansicolor (redhat section 3pm)

Term::ANSIColor(3pm)		 Perl Programmers Reference Guide	     Term::ANSIColor(3pm)

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 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).

       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, underscore, blink, reverse, concealed, black, red, green, yellow,
       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 intuitive to you.  The color alone sets the fore-
       ground color, and on_color sets the background color.

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

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

       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 argu-
       ment, 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.  Nor-
       mally 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, 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 con-
       stant.  In other words, with that variable set:

	   print BOLD BLUE "Text\n";

       will reset the display mode afterwards, whereas:

	   print BOLD, BLUE, "Text\n";

       will not.

       The subroutine interface has the advantage over the constants interface in that only two
       subroutines are exported into your namespace, versus twenty-two in the constants inter-
       face.  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 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 con-
	   stants 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 recog-
	   nized and can't be translated to names.

ENVIRONMENT
       ANSI_COLORS_DISABLED
	   If this environment variable is set, all of the functions defined by this module
	   (color(), colored(), and all of the constants not previously used in the program) 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.

	   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::ANSI-
       Color::AUTORESET.)

       For easier debuging, you may prefer to always use the commas when not setting $Term::ANSI-
       Color::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 (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 ear-
       lier 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 fol-
       lowed by some apparent garbage.

       Jean Delvare provided the following table of different common terminal emulators and their
       support for the various attributes:

		     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

       Where the entry is other than yes or no, that emulator interpret 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 emulators 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.ch/ecma1/STAND/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/software/ansicolor/>.  It is also part of the Perl core dis-
       tribution as of 5.6.0.

AUTHORS
       Original idea (using constants) by Zenin, reimplemented using subs by Russ Allbery
       <rra@stanford.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 <rra@stanford.edu> and Zenin
       <zenin@bawdycaste.org>.	This program is free software; you may redistribute it and/or
       modify it under the same terms as Perl itself.

perl v5.8.0				    2002-06-01			     Term::ANSIColor(3pm)


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