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CentOS 7.0 - man page for term::ansicolor (centos section 3pm)

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

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

	   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";

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

	   use Term::ANSIColor qw(colorstrip);
	   print colorstrip '\e[1mThis is bold\e[0m', "\n";

	   use Term::ANSIColor qw(colorvalid);
	   my $valid = colorvalid ('blue bold', 'on_magenta');
	   print "Color string is ", $valid ? "valid\n" : "invalid\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 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";

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

   Supported Colors
       Terminal emulators that support color divide into two types: ones that support only eight
       colors, and ones that support sixteen.  This module provides both the ANSI escape codes
       for the "normal" colors, supported by both types, as well as the additional colors
       supported by sixteen-color emulators.  These colors are referred to as ANSI colors 0
       through 7 (normal) and 8 through 15.

       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 sixteen colors
       or not, 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.

       Support for colors 8 through 15 (the "bright_" variants) was added in Term::ANSIColor 3.0.

   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, 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, 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 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, ATTRIBUTES)
       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.

	   uncolor() performs the opposite translation as color(), turning escape sequences into
	   a list of strings corresponding to the attributes being set by those sequences.

       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.

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




       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.)

       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 print the newline
       with a separate print statement to avoid confusing the terminal.

       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.  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
       As of Term::ANSIColor 2.0, 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.

       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.

       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";


	       @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
	   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.

	   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.

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

	   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

       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.

       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
	Mac Terminal  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.

       Note that codes 3 (italic), 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 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.

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

       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
       distribution as of 5.6.0.

       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 1996, 1997, 1998, 2000, 2001, 2002, 2005, 2006, 2008, 2009, 2010, 2011 Russ
       Allbery <rra@stanford.edu> and Zenin.  This program is free software; you may redistribute
       it and/or modify it under the same terms as Perl itself.

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

perl v5.16.3				    2013-03-04			     Term::ANSIColor(3pm)

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