Because you can only have one $_. But if I understand what you want to do you can try this:

open(KEYWORDS,"/tmp/file1") 
  or die "cannot open /tmp/file1: $!";
my %keywords=  map { ($_, 1) } <KEYWORDS>; # create a hash keyword => 
+1
open(STUFF_TO_MATCH,"/tmp/file2");
  or die "cannot open /tmp/file2: $!";
while(<STUFF_TO_MATCH>)
  { print "$_ matched!\n" if($keyword{$_}); }

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In reply to Re: Double While! by mirod
in thread Double While! by Anonymous Monk

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