Do you mean you want a condition that has to be met ONCE and then is "sticky"? Like: 
my $keep_going = 0;
while (my $job_B = readdir DIR_B) {
  print "D\n";

  # ||= here means "assign to $keep_going if $keep_going is false"
  $keep_going ||= $job_B =~ /Out_$tag\.txt$/;
  next unless $keep_going;

  ...
}

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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: next unless - and then 'until' by japhy
in thread next unless - and then 'until' by Win

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