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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<$ENV{PATH}>.
-
- Workaround is to invoke perl as
-
- perl ./filename
-
- =head1 AUTHORS
-
- FindBin is supported as part of the core perl distribution. Please send bug
- reports to E<lt>F<perlbug@perl.org>E<gt> using the perlbug program
- included with perl.
-
- Graham Barr E<lt>F<gbarr@pobox.com>E<gt>
- Nick Ing-Simmons E<lt>F<nik@tiuk.ti.com>E<gt>
-
- =head1 COPYRIGHT
-
- Copyright (c) 1995 Graham Barr & Nick Ing-Simmons. All rights reserved.
- This program is free software; you can redistribute it and/or modify it
- under the same terms as Perl itself.
-
- =cut
-
- package FindBin;
- use Carp;
- require 5.000;
- require Exporter;
- use Cwd qw(getcwd cwd abs_path);
- use Config;
- use File::Basename;
- use File::Spec;
-
- @EXPORT_OK = qw($Bin $Script $RealBin $RealScript $Dir $RealDir);
- %EXPORT_TAGS = (ALL => [qw($Bin $Script $RealBin $RealScript $Dir $RealDir)]);
- @ISA = qw(Exporter);
-
- $VERSION = "1.49";
-
-
- # 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
-