A simple matter of…

Techie one this. I wanted to do this:

  tail -f filename | awk '{ ...; exit}'

However this didn’t work – originally I thought awk had the pipe open, but it turned out that actually it was the tail hanging around and not dying (why it doesn’t acknowledge the SIGPIPE that I think it’ll get I’ve no idea).

Anyhow, after much anquish here’s the solution:

  awk '{ ...; exit}' <(tail -f filename)

Hopefully this will save someone else some pain. You might want to check the “–follow=name” option for tail too. If you just want to stop when you hit a particular word, you could use

  grep -m 1 name <(tail -f filename)

Keywords: tail -f; pipe; awk hanging