#!/migration/interwoven/teamsite/iw-perl/bin/iwperl
use strict;
use File::Find;
use File::Basename;

my $PATH = "/iwmnt/iwadmin/main/livesite/component/STAGING/";
my @comp = ();
find( \&filterComponent, $PATH );


print "<substitution>\n";
foreach my $component (sort @comp){
  (my $value = $component) =~ s#\.component##;
  my $opt = qq|<option label="$component" value="$value"/>|; 
  print $opt."\n";
}
print "</substitution>\n";

sub filterComponent {
  my @files = $File::Find::name;
  foreach my $file (@files){
     next unless !($file =~ m#\/Interwoven\/#);
     next unless !($file =~ m#\/Debug\/#);
     next unless !($file =~ m#\/LiveSite\/#);
     next unless !($file =~ m#\/Examples\/#);
     next unless !($file =~ m#\/News\/#);
     next unless !($file =~ m#\/Web\/#);
     $file = basename($file);
     next unless ($file =~ m#\.component$#) ;
     push (@comp, $file);
  }
}
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In this code, from where the packages File::Find and File::Basename are imported ? How do I know what functions are available in these packages ?