That means that:

# INCORRECT
sub something {
  $|++;
  # do something without buffering
  $|--;
}
[download]

Usually that's not really a problem, but if you need to revert autoflush to its previous setting, you have to remember its status yourself:

#CORRECT
sub something {
  my $flush = $|++;
  # do something without buffering
  $| = $flush;
}
[download]

#CORRECT
sub something {
  local $| = 1;
  # do something with autoflushing
}
[download]

I always forget there are uses for local().

:-)

"What should it profit a man, if he should win a flame war, yet lose his cool?"

Yes, of course you are correct. It's probably even a smidgen faster to just assign a 1 to $| than it is to perform the computation involved in incrementing. I don't think I've ever run into a situation where I wanted autoflush on a filehandle sometimes and then go back to buffering, but I'll keep that in mind.

I do like the use of setting the autoflush locally in your other post.

I'm nitpicking here, but note that $|++ does not increment $| when it's 1. $| is always 1 (flush) or 0 (buffer).

You can use =1 instead of ++ and you wouldn't have to explain this. Be nice to your reader and use =1.