I don't know why it works on one but not the other, but I can see a possible problem if two messages arrive in quick succession

You read only a single line from the pipe on each open, but you're using buffered input, so it's possible if two messages arrive in quick succession that for the <$fifo> PerlIO reads both lines into the buffer, and readline() (aka <>) returns the first of those two lines

You then re-open the pipe each time around the loop and discard the buffered line.

Given what you've shown I don't see why you don't just have a classic while (my $line = <$fifo>) { ... } loop.

In reply to Re: reading from a named pipe by tonyc
in thread reading from a named pipe by skendric

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