Oh, I see the problem. You can't just s/// on a line from a read-write filehandle and have the changes reflected in the file. You need to print the changed line back to the file. And that gets ugly and tricky if the size of the line has changed. You'd be best to do: 
while (<FILE_1>) {
  if (/regex/) {
    s/.../.../;
    s/.../.../;
    print FILE_2;
  }
}

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Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: Regexp Substitution on previously opened filehandle by japhy
in thread Regexp Substitution on previously opened filehandle by ghenry

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