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<!DOCTYPE html>
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    	<title>user goetia-shutdown</title>
    	<meta name="Description" content="Script to tear down a user supervision tree." />
    	<meta name="Keywords" content="goetia s6 s6-rc shutdown user supervision tree" />
	</head>
	<header>
		<p>
			<a href="//0x53.net/software/goetia/goetia-base">goetia-base</a>
			<br />
			<a href="//0x53.net/software/goetia">goetia</a>
			<br />
			<a href="//0x53.net/software">Software</a>
			<br />
			<a href="//0x53.net">0x53.net</a>
		</p>
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	<body>
		<h1>The user goetia-shutdown service</h1>
		<p>
			The user goetia-shutdown service is used to tear down
			<a href="//0x53.net/software/goetia/supervisiontree.html#user">user supervision trees</a>.
			Upon being started it:
		<ul>
			<li>
    			It reads the <code>USER</code> environment variable,
				if it is empty it exits 100.
			</li>
			<li>
    			It reads the <code>USERTREE</code> environment variable,
				If it is empty it exits 100.
			</li>
			<li>
    			It checks whether the subdirectory
				<code>${USER}/${USERTREE}</code>
				of the
				<a href="//0x53.net/software/goetia/rundir.html#user">user runtime directory</a>
				exists. If not, meaning no user supervision tree is running, it exits 0.
			</li>
			<li>
    			It makes all of its stdout and stderr go to the
				<a href="//0x53.net/software/goetia/goetia-base/service/user/s6-svscan-log.html">s6-svscan-log</a>
				of the user supervision tree.
			</li>
			<li>
    			It stops all services managed by
				<a href="https://skarnet.org/software/s6-rc/">s6-rc</a>.
			</li>
			<li>
    			It sends SIGHUP to s6-svscan-log of the user supervision tree.
				This is important, since s6-svscan will keep the fifo open,
				waiting for s6-svscan-log to exit, which in turn waits for
				EOF before exiting itself.
				SIGHUP tells s6-svscan-log to immediatly exit.
			</li>
			<li>
    			It tells
				<a href="https://skarnet.org/software/s6/s6-svscan.html">s6-svscan</a>
				to stop all remaining services and exit.
			</li>
		</ul>
	</body>
</html>