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<p>The statement, "Proper Unix fashion", leaves me somewhat
uncomfortable.<br>
</p>
<p>Since I'm ancient, my understanding of <font size="4"><tt>SIGHUP</tt></font>
is to handle a hangup detected on the controlling terminal or the
death of a controlling process. A hangup started out meaning
dropping carrier on a modem or DTR on a hardwired line. It came
to include a broken network terminal connection.<br>
</p>
<p>When I think of how to handle a <font size="4"><tt>SIGHUP</tt></font>,
I usually think of 'gracefully' stopping a process (I.E., saving
the user's work instead of ditching it) and exiting. If you don't
do that, then something else has to be used to get rid of you,
perhaps a <font size="4"><tt>SIGTERM</tt></font>. The problem is
that if somebody wants you gone and you don't go away, you have a
9 on your hands (<font size="4"><tt>SIGKILL</tt></font>). Now
that data is gone.<br>
</p>
<p>If you usurp <font size="4"><tt>SIGHUP</tt></font> for such use,
then things like <font size="4"><tt>NOHUP</tt></font> won't do
the expected thing. There are certainly reasons to be <font
size="4" face="monospace">NOHUP</font>'ed. In your superior
breaks, you might not want to disappear so somebody has a chance
to attach a debugger to you to try to figure out what happened.<br>
</p>
<p>I think the better thing to do would be handle a <font size="4"><tt>SIGUSR1</tt></font>/<font
size="4"><tt>SIGUSR2</tt></font> to reparse.<br>
</p>
<p>Of course, "proper" is a very relative term in Unix. Things
change and sometimes get used for no readily apparent reason, the
result being that an unspoken 'standard' happens. It is not
uncommon. For example, Johnny's DECnet bridge does in fact use <font
size="4"><tt>SIGUSR1</tt></font> to display some information.
However, it uses a <font size="4"><tt>SIGHUP</tt></font> to do a
reparse. So maybe that's the best of both worlds...<br>
</p>
<div class="moz-cite-prefix">I've never felt strongly enough about
the matter to suggest <font size="4"><tt>SIGUSR2</tt></font> for
a reparse, but if you want to be a purist, then it probably
should.<br>
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<blockquote type="cite"
cite="mid:397CB99E-107B-4CAF-8CAA-447C741BE8F1@comcast.net">
<hr width="100%" size="2">
<pre class="moz-quote-pre" wrap="">On 11/18/21 9:58 AM, Paul Koning wrote:
In proper Unix fashion it could be triggered by a SIGHUP signal</pre>
</blockquote>
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