in reply to how to process several zipped files

Update: My apologies. I read "gzipped" where you had written plain old "zipped". Please disregard my answer below.

Don't unzip; use the PerlIO gzip layer: 

use PerlIO::gzip;
open my $in, '<:gzip', 'foo.txt.gz' or die $!;
while (<$in>) {
  #etc;
}

[download]
See PerlIO::gzip. You need 5.8.x, though.

the lowliest monk

In Section Seekers of Perl Wisdom