<p><pre><code>  &gt; And hangup doesn&#x27;t have anything to do with terminating.
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The default hangup action is termination because people generally don&#x27;t want interactive processes sticking around after their I&#x2F;O is gone.<p><pre><code>  &gt; how often do you actually send TERM?
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Each common termination trigger has its own signal so that programs can distinguish the source and potentially act differently for each — HUP for hangup, INTR for tty, TERM for kill(1).