############# UNTESTED ################
  use strict;

  my $pvid = '';           # initialize 
  my @output = `command`;  # Output looks like 7 lines and on [one] line is the pvid:
                           #    pvid 00c1be9a467335ce0000000000000000
                           # I use qx/command/; # easier to see in code for me!
  foreach my $line ( @output )
  {  # print "$line\n";   ## If not working, use print to figure out what's happening
     if ( substr( $line, 0, 5 ) eq 'pvid ' )
     {   $pvid = substr( $line, 6, 16 )     #  or '32' as you require
         last;
     }
  }
  if ( $pvid eq '' ) { ... }    ## Generate warning or do some error handling!