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What this is
This file is included in the DevDaily.com
"Perl Source Code
Warehouse" project. The intent of this project is to help you "Learn
Perl by Example" TM.
Other links
The source code
# 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 "$Bin/../lib";
=head1 DESCRIPTION
Locates the full path to the script bin directory to allow the use
of paths relative to the bin directory.
This allows a user to setup a directory tree for some software with
directories ErootE/bin and ErootE/lib and then the above example will allow
the use of modules in the lib directory without knowing where the software
tree is installed.
If perl is invoked using the B<-e> option or the perl script is read from
C then FindBin sets both C<$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 from different directories
under the same interpreter, this won't work. Since C uses a
C 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 in modules that you plan to put
on CPAN. To make sure that C will work is to call the C
function:
use FindBin;
FindBin::again(); # or FindBin->again;
In former versions of FindBin there was no C function. The
workaround was to force the C block to be executed again:
delete $INC{'FindBin.pm'};
require FindBin;
=head1 KNOWN BUGS
If perl is invoked as
perl filename
and I does not have executable rights and a program called I
exists in the users C<$ENV{PATH}> which satisfies both B<-x> and B<-T> then FindBin
assumes that it was invoked via the C<$ENV{PATH}>.
Workaround is to invoke perl as
perl ./filename
=head1 AUTHORS
FindBin is supported as part of the core perl distribution. Please send bug
reports to EFE using the perlbug program included with perl.
Graham Barr EFE
Nick Ing-Simmons EFE
=head1 COPYRIGHT
Copyright (c) 1995 Graham Barr & Nick Ing-Simmons. All rights reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
=cut
package FindBin;
use Carp;
require 5.000;
require Exporter;
use Cwd qw(getcwd abs_path);
use Config;
use File::Basename;
use File::Spec;
@EXPORT_OK = qw($Bin $Script $RealBin $RealScript $Dir $RealDir);
%EXPORT_TAGS = (ALL => [qw($Bin $Script $RealBin $RealScript $Dir $RealDir)]);
@ISA = qw(Exporter);
$VERSION = "1.44";
sub init
{
*Dir = \$Bin;
*RealDir = \$RealBin;
if($0 eq '-e' || $0 eq '-')
{
# perl invoked with -e or script is on C
$Script = $RealScript = $0;
$Bin = $RealBin = getcwd();
}
else
{
my $script = $0;
if ($^O eq 'VMS')
{
($Bin,$Script) = VMS::Filespec::rmsexpand($0) =~ /(.*\])(.*)/s;
($RealBin,$RealScript) = ($Bin,$Script);
}
else
{
my $dosish = ($^O eq 'MSWin32' or $^O eq 'os2');
unless(($script =~ m#/# || ($dosish && $script =~ m#\\#))
&& -f $script)
{
my $dir;
foreach $dir (File::Spec->path)
{
my $scr = File::Spec->catfile($dir, $script);
if(-r $scr && (!$dosish || -x _))
{
$script = $scr;
if (-f $0)
{
# $script has been found via PATH but perl could have
# been invoked as 'perl file'. Do a dumb check to see
# if $script is a perl program, if not then $script = $0
#
# well we actually only check that it is an ASCII file
# we know its executable so it is probably a script
# of some sort.
$script = $0 unless(-T $script);
}
last;
}
}
}
croak("Cannot find current script '$0'") unless(-f $script);
# Ensure $script contains the complete path incase we C
$script = File::Spec->catfile(getcwd(), $script)
unless File::Spec->file_name_is_absolute($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
$Bin = abs_path($Bin) if($Bin);
$RealBin = abs_path($RealBin) if($RealBin);
}
}
}
BEGIN { init }
*again = \&init;
1; # Keep require happy
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