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Subject: kill -0 <pid> --- side effect or supported
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Date: Fri, 3 Mar 2017 23:12:26 +0100
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I regularly use  'kill -0 <pid>' on FreeBSD as  a way to test if a =
certain process is still running (but without actually sending the =
signal). And I think it has worked reliably since the mid 80's.

Is it actually a properly supported use - as I recently happened to =
notice that it does not seem to be all that documented in kill(

Dw.