Do not use SO_REUSEPORT on WSL

[pixelspark]

In PR #61 (e639a3f), use of the SO_REUSEPORT socket option was added. This however causes issues on Windows Subsystem for Linux (WSL), which does not (and will likely never) support SO_REUSEPORT.

Strace shows the following:

setsockopt(15, SOL_SOCKET, SO_REUSEPORT, [1], 4) = -1 ENOPROTOOPT (Protocol not available)

By the way, SO_REUSEADDR works without issue on WSL:

setsockopt(15, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0

Please consider adding a way to disable the use of SO_REUSEPORT, or do not fail with an exception (but rather silently) when the call to setsockopt fails with ENOPROTOOPT (at least on Linux). Unfortunately it is not possible to detect WSL at compile-time, as the userland is actually Ubuntu (or other Linux). A third option would be to perform detection at runtime (or perform some other check to see whether SO_REUSEPORT is available) but then again, that is probably more complicated than simply ignoring an ENOPROTOOPT error.

[billabt]

Fixed in the latest release, 0.12.57. It now will fail silently should the errno be set to ENOPROTOOPT. Thanks.