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copied!<p>All remotely modern systems have <code>poll</code>, and it's a greatly superior interface to <code>select</code>/<code>pselect</code> in almost all ways:</p> <ul> <li><code>poll</code> allows more fine-grained detection of status than <code>select</code>.</li> <li><code>poll</code> does not have limits on the max file descriptor you can use (and more importantly, does not have critical vulnerabilities when you fail to check for file descriptors past the <code>FD_SETSIZE</code> limit).</li> </ul> <p>The only disadvantages I can think of to using <code>poll</code> are that:</p> <ul> <li>unlike <code>pselect</code>, <code>poll</code> cannot atomically unmask/mask signals, so you can't use it for waiting for a set of events that includes both file descriptor activity and signals unless you resort to the self-pipe trick.</li> <li><code>poll</code> only has millisecond resolution for the wait timeout, rather than microsecond (<code>select</code>) or nanosecond (<code>pselect</code>).</li> </ul> <p>Certainly portability of <code>poll</code> is not a consideration anymore. Any system old enough to lack <code>poll</code> is full of so many vulnerabilities it should not be connected to a network.</p> <p>In summary, unless you have very special needs (tiny timeout intervals, nasty signal interactions, scaling to millions of persistent connections, etc.) I would simply use <code>poll</code> and be done with it. As others have mentioned, <code>libevent</code> is also an option, but it's not clean/safe code (its use of <code>select</code> actually invokes dangerous UB trying to workaround the limitations of <code>select</code>!) and I find code that uses <code>libevent</code> is generally a lot more unnecessarily complicated than code that simply uses <code>poll</code> directly.</p>

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