Add support for epoll polling mode

[designinlife]

Is polling in epoll mode?

[samhocevar]

No, it uses plain old select. The software was written in 1997, at a time when poll was not yet standard.

[fivetime]

Can you add support for epoll?

[notcomsed]

I write a fork use epoll instead of select,but it base on https://github.com/boutell/rinetd, so I cannot pull requests. And orther fork like https://github.com/rogerwangzy/rinetdplus, use ae(epoll) to replace select. This is my fork https://github.com/notcomsed/rinetd-epoll .

[marcin-gryszkalis]

There's also patch in FreeBSD ports: https://github.com/freebsd/freebsd-ports/blob/main/net/rinetd/files/patch-select2poll
I looked at it as I'm trying to update this port to current rinetd - but I think that it makes more sense to switch to libevent and get support for all modern tech like epoll on linux, kqueue on freebsd etc.