# FindBin.pm
#
# Copyright (c) 1995 Graham Barr & Nick Ing-Simmons. All rights reserved.
# This program is free software; you can redistribute it and/or modify it
# under the same terms as Perl itself.

=head1 NAME

FindBin - Locate directory of original perl script

=head1 SYNOPSIS

use FindBin;
use lib "$FindBin::Bin/../lib";

or

use FindBin qw($Bin);
use lib "$Bin/../lib";

=head1 DESCRIPTION

Locates the full path to the script bin directory to allow the use
of paths relative to the bin directory.

This allows a user to setup a directory tree for some software with
directories C<< <root>/bin >> and C<< <root>/lib >>, and then the above
example will allow the use of modules in the lib directory without knowing
where the software tree is installed.

If perl is invoked using the B<-e> option or the perl script is read from
C<STDIN> then FindBin sets both C<$Bin> and C<$RealBin> to the current
directory.

=head1 EXPORTABLE VARIABLES

$Bin - path to bin directory from where script was invoked
$Script - basename of script from which perl was invoked
$RealBin - $Bin with all links resolved
$RealScript - $Script with all links resolved

=head1 KNOWN ISSUES

If there are two modules using C<FindBin> from different directories
under the same interpreter, this won't work. Since C<FindBin> uses a
C<BEGIN> block, it'll be executed only once, and only the first caller
will get it right. This is a problem under mod_perl and other persistent
Perl environments, where you shouldn't use this module. Which also means
that you should avoid using C<FindBin> in modules that you plan to put
on CPAN. To make sure that C<FindBin> will work is to call the C<again>
function:

use FindBin;
FindBin::again(); # or FindBin->again;

In former versions of FindBin there was no C<again> function. The
workaround was to force the C<BEGIN> block to be executed again:

delete $INC{'FindBin.pm'};
require FindBin;

=head1 AUTHORS

FindBin is supported as part of the core perl distribution. Please send bug
reports to E<lt>F<[email protected]>E<gt> using the perlbug program
included with perl.

Graham Barr E<lt>F<[email protected]>E<gt>
Nick Ing-Simmons E<lt>F<[email protected]>E<gt>

=head1 COPYRIGHT

Copyright (c) 1995 Graham Barr & Nick Ing-Simmons. All rights reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.

=cut

package FindBin;
use Carp;
require 5.000;
require Exporter;
use Cwd qw(getcwd cwd abs_path);
use File::Basename;
use File::Spec;

@EXPORT_OK = qw($Bin $Script $RealBin $RealScript $Dir $RealDir);
%EXPORT_TAGS = (ALL => [qw($Bin $Script $RealBin $RealScript $Dir $RealDir)]);
@ISA = qw(Exporter);

$VERSION = "1.51";


# needed for VMS-specific filename translation
if( $^O eq 'VMS' ) {
require VMS::Filespec;
VMS::Filespec->import;
}

sub cwd2 {
my $cwd = getcwd();
# getcwd might fail if it hasn't access to the current directory.
# try harder.
defined $cwd or $cwd = cwd();
$cwd;
}

sub init
{
*Dir = \$Bin;
*RealDir = \$RealBin;

if($0 eq '-e' || $0 eq '-')
{
# perl invoked with -e or script is on C<STDIN>
$Script = $RealScript = $0;
$Bin = $RealBin = cwd2();
$Bin = VMS::Filespec::unixify($Bin) if $^O eq 'VMS';
}
else
{
my $script = $0;

if ($^O eq 'VMS')
{
($Bin,$Script) = VMS::Filespec::rmsexpand($0) =~ /(.*[\]>\/]+)(.*)/s;
# C<use disk:[dev]/lib> isn't going to work, so unixify first
($Bin = VMS::Filespec::unixify($Bin)) =~ s/\/\z//;
($RealBin,$RealScript) = ($Bin,$Script);
}
else
{
croak("Cannot find current script '$0'") unless(-f $script);

# Ensure $script contains the complete path in case we C<chdir>

$script = File::Spec->catfile(cwd2(), $script)
unless File::Spec->file_name_is_absolute($script);

($Script,$Bin) = fileparse($script);

# Resolve $script if it is a link
while(1)
{
my $linktext = readlink($script);

($RealScript,$RealBin) = fileparse($script);
last unless defined $linktext;

$script = (File::Spec->file_name_is_absolute($linktext))
? $linktext
: File::Spec->catfile($RealBin, $linktext);
}

# Get absolute paths to directories
if ($Bin) {
my $BinOld = $Bin;
$Bin = abs_path($Bin);
defined $Bin or $Bin = File::Spec->canonpath($BinOld);
}
$RealBin = abs_path($RealBin) if($RealBin);
}
}
}

BEGIN { init }

*again = \&init;

1; # Keep require happy