BTW, if you open/close the filehandle inside the loop (and perhaps include $$ in the output) it is less probable that multiple processes mess up the logfiles

I don't think so. Usually, the OS provides atomic write operations up to a certain length. If your write operations go over that limit, the way to ensure that data from different processes does not interleave is to lock the file.

Reopening the file on every write allows to rotate the logs from the outside without the current script knowing.

In reply to Re^4: How to log all output from a program? by salva
in thread How to log all output from a program? by absolut.todd

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