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# 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 $INC{'FindBin.pm'};
require FindBin;
=head1 KNOWN BUGS
If perl is invoked as
perl filename
and I<filename> does not have executable rights and a program called
I<filename> exists in the users C<$ENV{PATH}> which satisfies both B<-x>
and B<-T> then FindBin assumes that it was invoked via the
C<$ENV{PATH}>.
Workaround is to invoke perl as
perl ./filename
=head1 AUTHORS
FindBin is supported as part of the core perl distribution. Please send bug
reports to E<lt>F<perlbug@perl.org>E<gt> using the perlbug program
included with perl.
Graham Barr E<lt>F<gbarr@pobox.com>E<gt>
Nick Ing-Simmons E<lt>F<nik@tiuk.ti.com>E<gt>
=head1 COPYRIGHT
Copyright (c) 1995 Graham Barr & Nick Ing-Simmons. All rights reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
=cut
package FindBin;
use Carp;
require 5.000;
require Exporter;
use Cwd qw(getcwd cwd abs_path);
use File::Basename;
use File::Spec;
@EXPORT_OK = qw($Bin $Script $RealBin $RealScript $Dir $RealDir);
%EXPORT_TAGS = (ALL => [qw($Bin $Script $RealBin $RealScript $Dir $RealDir)]);
@ISA = qw(Exporter);
$VERSION = "1.50";
# 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
{
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);
# $script can 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 keep $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.
if(-f $scr && -r _ && ($dosish || -x _) && -s _ && -T _)
{
$script = $scr;
last;
}
}
}
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
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