Env-Bash version 0.00_05
========================

NAME
    Env::Bash - Perl extension for accessing _aLL_ bash environment
    variables.

INSTALLATION
    To install this module type the following:

       perl Makefile.PL
       make
       make test
       make install

DEPENDENCIES
    This module requires these other modules and libraries:

       Perl        >= 5.8.0.
       Test::More  >= 0.50 ( in the perl distribution ).

SYNOPSIS
      use Env::Bash;

    Standard interface:

      my @var = get_env_var( "SORCERER_MIRRORS",
                             Source => "/etc/sorcery/config", );
      print "SORCERER_MIRRORS via get_env_var:\n",
      join( "\n", @var ), "\ncount = ", scalar @var, "\n";
  
      @var = Env::Bash::SORCERER_MIRRORS
          ( Source => "/etc/sorcery/config", );
      print "SORCERER_MIRRORS via name:\n",
      join( "\n", @var ), "\ncount = ", scalar @var, "\n";
  
      my @keys = get_env_keys( Source => "/etc/sorcery/config",
                               SourceOnly => 1, );
      print "first 10 keys:\n", map { " $_\n" } @keys[0..9];

    Object oriented interface:

      my $be = Env::Bash->new( Source => "/etc/sorcery/config",
                               Keys => 1, );
      my @var = $be->get( "SORCERER_MIRRORS" );
      print "SORCERER_MIRRORS via get:\n",
      join( "\n", @var ), "\ncount = ", scalar @var, "\n";
      
      @var = $be->SORCERER_MIRRORS;
      print "SORCERER_MIRRORS via name:\n",
      join( "\n", @var ), "\ncount = ", scalar @var, "\n";
  
      $be = Env::Bash->new( Keys => 1,);
      @var = $be->HOSTTYPE;
      print "HOSTTYPE via name:\n",
      join( "\n", @var ), "\ncount = ", scalar @var, "\n";
  
      if( $be->exists( 'BASH_VERSINFO' ) ) {
          print "BASH_VERSINFO =>\n ",
          join( "\n ", $be->BASH_VERSINFO ), "\n";
      }
  
      my %options = $be->options( [], Keys => 1 );

    Tie HASH interface:

      my %env = ();
      tie %env, "Env::Bash", Source => "/etc/sorcery/config", ForceArray => 1;
  
      my $var = $env{SORCERER_MIRRORS};
      print "SORCERER_MIRRORS via tied hash:\n",
      join( "\n", @$var ), "\ncount = ", scalar @$var, "\n";
  
      $var = $env{HOSTTYPE};
      print "HOSTTYPE via tied hash:\n",
      join( "\n", @$var ), "\ncount = ", scalar @$var, "\n";
  
      while( my( $key, $value ) = each %env ) {
          print "$key =>\n ", join( "\n ", @$value ), "\n";
      } 

DESCRIPTION
    Env::Bash enables perl access to ALL bash environment variables (
    including those that may be bash arrays ). But you say: "That doesn't
    make sense; perl already has the %ENV hash. Why not use that?". Well,
    please run:

      $ perl -e 'print "$_ = $ENV{$_}\n" for sort keys %ENV;'

    and:

      $ set | grep "^[A-Z]"

    Now compare the outputs. See, perl's list is much shorter than the bash
    list. This is because the environment passed to perl contains only
    variables that have been exported( I think ). There is no pure-perl way
    to get all the variables in the running shell; also, forget about
    getting all the elements of variables that are bash arrays!

    In the following discussion and examples, I show how I use this module
    with Linux Sorcerer. For my fellow Sorcererites, this is fine, for
    others, please see "A SHAMELESS PLUG FOR LINUX SORCERER" below.

  Options
    The following options, specified as func( ..., key1 => value1, ..., )
    are provided.

    Debug
        Prints debugging information to STDERR.

        Values 0 or 1, default 0.

    ForceArray or []
        Defines how environment variable data are returned. Especially
        useful if you expect to handle bash array variables. For example, an
        array variable, 'BASH_VERSINFO', returns data as follows:

                               scalar context      list context
                               --------------      ------------
          ForceArray => 0            3             ( 3,
                                                     00,
                                                     0,
                                                     1.
                                                     'release',
                                                     'i686-pc-linux-gnu' )
          ForceArray => 1         reference        ( 3,
                                  to array           00,
                                  returned in        0,
                                  list context.      1.
                                                     'release',
                                                     'i686-pc-linux-gnu' )

        As a shortcut, ForceArray may be specified by placing the empty
        array reference token '[]' as the first, and only first, argument of
        the option arguments.

        Values 0 or 1, default 0.

    SelectRegex
        The regular expression to select which environment variables to
        read. It may be any valid perl regular expression.

        Values valid perl regex, default: none.

    Keys
        Whether or not to load an array of environment variable names.

        Values 0 or 1, default 0.

    Source
        The path name of one or more executable bash scripts with which to
        'source' ( execute with a leading dot ) before extracting
        environment. Any variables set in these scripts is then available
        for this module. The leading dot is prepended if not supplied.

        More than one source file may be specified as a scalar of semicolon
        separated source file names:

          Source => '/etc/bebe/configure.sh;/etc/sorcery/config',

        or an array reference:

          Source => [ qw( /etc/bebe/configure.sh /etc/sorcery/config ) ],

        Values: any list of executable bash scripts, Default none.

    SourceOnly
        Returns only the environment variables defined by the Source
        script(s). Some bash-generated environment variables may 'sneak'
        through, notably, 'PIPESTATUS'.

        Values 0 or 1, default 0.

    WARNING
        SourceOnly is handled by reading all the current environment
        variables ( without sourcing the entries in Source ), then reading
        all the variable ( including Source ), and removing any variable
        that does not appear in both lists. If you have exported a variable
        that you are sourcing in the shell where your script will run, it
        will NOT appear in the returned list. SourceOnly is of limited value
        and should only be used when you really want only the keys from your
        sourced scripts. 'get', 'get_env_var', and tie access to variables
        are not affected by SourceOnly.

  Standard interface
    The non-object oriented interface.

   get_env_var
    prototype
        get_env_var( options...);

    options used
        Debug, ForceArray, SelectRegex, Source, SourceOnly.

    operation
        Returns the contents of the specified environment variable in scalar
        or list context as described above. If the requested variable is not
        present, a false value ( not 'undef' ) is returned.

   Env::Bash::VARIABLE_NAME
    prototype
        Env::Bash::VARIABLE_NAME( options...);

    note
        This is the AUTOLOAD version of 'get_env_var'.

   get_env_keys
    prototype
        get_env_keys( options...);

    options used
        Debug, ForceArray, SelectRegex, Source, SourceOnly.

    operation
        Returns a sorted array ( list context ) or an array reference (
        scalar context ) of the keys in the current bash environment.

  Object oriented interface
   new
    prototype
        Env::Bash->new( options... );

    options used
        Debug, ForceArray, SelectRegex, Keys, Source, SourceOnly.

    operation
        Returns a Env::Bash object with the specified options saved in the
        object so they do not have to be repeated in subsequent method
        calls.

   get
    prototype
        $env_bash_obj->get( options... );

    options used
        Debug, ForceArray, SelectRegex, Source, SourceOnly.

    operation
        Returns the contents of the specified environment variable in scalar
        or list context as described above. If the requested variable is not
        present, a false value ( not 'undef' ) is returned.

   VARIABLE_NAME
    prototype
        $env_bash_obj->VARIABLE_NAME( options... );

    options used
        Debug, ForceArray, SelectRegex, Source, SourceOnly.

    operation
        This is the AUTOLOAD version of 'get'.

   exists
    prototype
        $env_bash_obj->exists( 'VARIABLE_NAME' );

    options used
        None.

    operation
        Returns true or false to indicate whether or not the environment
        exists.

   keys
    prototype
        $env_bash_obj->keys( options... );

    options used
        Debug, ForceArray, SelectRegex, Source, SourceOnly.

    operation
        Returns a sorted array ( list context ) or an array reference (
        scalar context ) of the keys in the current bash environment.

   reload_keys
    prototype
        $env_bash_obj->reload_keys( options... );

    options used
        Debug, ForceArray, SelectRegex, Source, SourceOnly.

    operation
        Reloads the environment key array and returns a sorted array ( list
        context ) or an array reference ( scalar context ) of the keys in
        the current bash environment.

   options
    prototype
        $env_bash_obj->options( options... );

    options used
        ANY.

    operation
        Returns a the current options hash after setting any options
        specified.

  Tie HASH interface
   tie
    prototype
          my %env = ();
          tie %env, "Env::Bash", options...;

    options used
        Debug, ForceArray, SelectRegex, Keys, Source, SourceOnly.

    operation
        Ties a hash variable to Env::Bash. The resulting hash may be used
        like a normal hash, except it is read-only. Note: if ForceArray is
        specified, the resulting hash is a hash of array references.

   hash operations
    allowed
        access ( $var = $env{SOME_VARIABLE_NAME} ), exists, each, keys,
        values,

    not allowed
        assign ( $env{SOME_VARIABLE_NAME} = $var ), delete, clear ( as %env
        = (); ).

    note
        Unlike normal hashes, the keys are maintained in sorted order,
        therefore there is no need tor use the '... sort keys ...' construct
        unless you wish to process in some non-standard order.

  Export
    get_env_var and get_env_keys are unconditionally exported.

A SHAMELESS PLUG FOR LINUX SORCERER
    Linux Sorcerer, by Kyle Sallee, is a great Linux distribution. It gives
    you one of the most up-to-date and fastest Linux systems available.
    Sorcerer is based upon package 'source', not pre-compiled rpm's. You (
    with the bash scripts supplied by Sorcerer ) compile and install the
    packages optimized to your machine. You configure your own kernel for
    the best, leanest kernel matching your environment. Current packages are
    made available as soon as they are stable; you do not have to wait six
    months for the next release of your distribution.

    With the gain there is always the pain:

    Installing updated packages is slower.
    The documentation is wanting.
    No fancy 'x' windows installer; the command line rules!
    Not for the beginner.

    All and all, I love it! Check it out at <http://sorcerer.wox.org>

SEE ALSO
    The 'Advanced Bash-Scripting Guide' at
    <http://www.tldp.org/LDP/abs/html/>.

AUTHOR
    Beau E. Cox, <beaucox@hawaii.rr.com>.

COPYRIGHT AND LICENSE
    Copyright (C) 2004 by Beau E. Cox.

    This library is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself, either Perl version 5.8.6 or, at
    your option, any later version of Perl 5 you may have available.

