Merge branch 'vlb' into blead

[perl5.git] / lib / FindBin.pm

diff --git a/lib/FindBin.pm b/lib/FindBin.pm
index 91958a8..cf6ecf2 100644 (file)
--- a/lib/FindBin.pm
+++ b/lib/FindBin.pm
@@ -24,9 +24,9 @@ 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 E<lt>rootE<gt>/bin and E<lt>rootE<gt>/lib and then the above example will allow
-the use of modules in the lib directory without knowing where the software
-tree is installed.
+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
@@ -39,24 +39,31 @@ directory.
  $RealBin     - $Bin with all links resolved
  $RealScript  - $Script with all links resolved
 
-=head1 KNOWN BUGS
+=head1 KNOWN ISSUES
 
-if perl is invoked as
+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:
 
-   perl filename
+  use FindBin;
+  FindBin::again(); # or FindBin->again;
 
-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}>.
+In former versions of FindBin there was no C<again> function. The
+workaround was to force the C<BEGIN> block to be executed again:
 
-Workaround is to invoke perl as
-
- perl ./filename
+  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<perlbug@perl.org>E<gt> using the perlbug program included with perl.
+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>
@@ -73,8 +80,7 @@ package FindBin;
 use Carp;
 require 5.000;
 require Exporter;
-use Cwd qw(getcwd abs_path);
-use Config;
+use Cwd qw(getcwd cwd abs_path);
 use File::Basename;
 use File::Spec;
 
@@ -82,9 +88,24 @@ use File::Spec;
 %EXPORT_TAGS = (ALL => [qw($Bin $Script $RealBin $RealScript $Dir $RealDir)]);
 @ISA = qw(Exporter);
 
-$VERSION = "1.42";
+$VERSION = "1.51";
+
+
+# needed for VMS-specific filename translation
+if( $^O eq 'VMS' ) {
+    require VMS::Filespec;
+    VMS::Filespec->import;
+}
 
-BEGIN
+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;
@@ -92,9 +113,9 @@ BEGIN
  if($0 eq '-e' || $0 eq '-')
   {
    # perl invoked with -e or script is on C<STDIN>
-
    $Script = $RealScript = $0;
-   $Bin    = $RealBin    = getcwd();
+   $Bin    = $RealBin    = cwd2();
+   $Bin = VMS::Filespec::unixify($Bin) if $^O eq 'VMS';
   }
  else
   {
@@ -102,45 +123,18 @@ BEGIN
 
    if ($^O eq 'VMS')
     {
-     ($Bin,$Script) = VMS::Filespec::rmsexpand($0) =~ /(.*\])(.*)/s;
+     ($Bin,$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 $doshish = ($^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<chdir>
+     # Ensure $script contains the complete path in case we C<chdir>
 
-     $script = File::Spec->catfile(getcwd(), $script)
+     $script = File::Spec->catfile(cwd2(), $script)
        unless File::Spec->file_name_is_absolute($script);
 
      ($Script,$Bin) = fileparse($script);
@@ -159,11 +153,18 @@ BEGIN
       }
 
      # Get absolute paths to directories
-     $Bin     = abs_path($Bin)     if($Bin);
+     if ($Bin) {
+      my $BinOld = $Bin;
+      $Bin = abs_path($Bin);
+      defined $Bin or $Bin = File::Spec->canonpath($BinOld);
+     }
      $RealBin = abs_path($RealBin) if($RealBin);
     }
   }
 }
 
-1; # Keep require happy
+BEGIN { init }
+
+*again = \&init;
 
+1; # Keep require happy