Hi, I'm looking for something very similar. I have an array of strings, which I want to match to the end of log file entries. At first I did something similar to the original poster:

my @zones = `cat zones.txt`;
chomp (@zones);

open (IN, 'logfile.log');
while (<IN>) {
  chomp;
  foreach my $zone (@zones) {
    if ($_ =~ /$zone$/) {
      print "$zone match\n";
      last;
    }
  }
}
close IN;
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But obviously that's rather inefficient and takes for ever. Could your example, of joining the array to a regular expression string, be modified and used in this case where it needs to match the end of the string?