You better print something, like print OUTFILE $lines;. Moreover, it's not optimal to read into memory the whole contents of files. Give this a try:

## Untested
open my $match_in, '<', $match_file or die "1st open failed: $!";
open my $fh_in, '<', $in_file       or die "2nd open failed: $!";
open my $fh_out, '>>', $out_file    or die "3rd open failed: $!";

while (my $lines = <$fh_in>) {
  while (my $matches = <$match_in>) {
    chomp $matches;
    my $matchtmp = qr/$matches.*(?:SUPSOSODEV|AJTSOSO(?:CFD|ISI|CLA))/
+;
    ## Assuming you want to print $lines
    print $fh_out $lines if $lines =~ m/$matchtmp/;
  }
}

close $fh_out;
close $fh_in;
close $match_in;

[download]

--
David Serrano

In reply to Re: "Use of uninitialized value in print" but why ??? by Hue-Bond
in thread "Use of uninitialized value in print" but why ??? by ultibuzz

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