OsPoller.registerHandle
int registerHandle(Handle handle, IoInterest interest, ulong userData, WatcherFlags flags = WatcherFlags.none) @trusted nothrow @nogcRegister a handle with the active backend.
int registerHandle(Handle handle, IoInterest interest, ulong userData, WatcherFlags flags = WatcherFlags.none) @trusted nothrow @nogcRegister a handle with the active backend.