+ if(!event_count) {
+ Sleep(timeout_ms);
+ continue;
+ }
+
+ /*
+ For some reason, Microsoft decided to make the FD_WRITE event edge-triggered instead of level-triggered,
+ which is the opposite of what select() does. In practice, that means that if a FD_WRITE event triggers,
+ it will never trigger again until a send() returns EWOULDBLOCK. Since the semantics of this event loop
+ is that write events are level-triggered (i.e. they continue firing until the socket is full), we need
+ to emulate these semantics by making sure we fire each IO_WRITE that is still writeable.
+
+ Note that technically FD_CLOSE has the same problem, but it's okay because user code does not rely on
+ this event being fired again if ignored.
+ */
+ io_t *writeable_io = NULL;
+
+ for splay_each(io_t, io, &io_tree)
+ if(io->flags & IO_WRITE && send(io->fd, NULL, 0, 0) == 0) {
+ writeable_io = io;
+ break;
+ }
+
+ if(writeable_io) {
+ writeable_io->cb(writeable_io->data, IO_WRITE);
+ continue;
+ }
+
+ WSAEVENT *events = xmalloc(event_count * sizeof(*events));
+ DWORD event_index = 0;