#!/usr/bin/perl
use strict;
use warnings;

if (!-d "sorted")
{
    mkdir "sorted" or die "unable to create dir sorted $!";
}

my @files2sort = <file*.txt>;  #just use glob to get names
my $curfilenum =1;

foreach my $file (@files2sort)
{
   open my $fh_in, '<', $file  or die "$file failed to open $!";
   open(my $fh_out, '>', "./sorted/$file.sort") or die "cannot create out $file.sort $!";
   
   print "Processing ".$curfilenum++." of ".@files2sort." $file\n";
   sortfile2($fh_in, $fh_out);

   close ($fh_out);
   close ($fh_in);
   print "OK: Sorted $file \n";
}


sub sortfile2
{
   my ($fh_in, $fh_out) = @_;
      
   my @lines = <$fh_in>;
      
   @lines = sort by_version @lines;
         
   print $fh_out @lines;  #can do a sort "in place"
                          #separate @sorted var is not needed.

}

sub by_version
{
   my ($verA) = $a =~ /VerNumber:\((\d+)/i;
   my ($verB) = $b =~ /VerNumber:\((\d+)/i;
          $verA <=> $verB    #returns -1,0,+1
}

__END__
Processing 1 of 2 file1.txt
OK: Sorted file1.txt 
Processing 2 of 2 file2.txt
OK: Sorted file2.txt