+ FD_ZERO(&rset);
+ FD_ZERO(&wset);
+ FD_ZERO(&xset);
+ maxfd = 0;
+
+ /*
+ * Add all currently open fds to the select sets, and store
+ * them in fdlist as well.
+ */
+ fdcount = 0;
+ for (fd = first_fd(&fdstate, &rwx); fd >= 0;
+ fd = next_fd(&fdstate, &rwx)) {
+ fdlist[fdcount++] = fd;
+ if (rwx & 1)
+ FD_SET_MAX(fd, maxfd, rset);
+ if (rwx & 2)
+ FD_SET_MAX(fd, maxfd, wset);
+ if (rwx & 4)
+ FD_SET_MAX(fd, maxfd, xset);
+ }
+
+ if (include_stdin)
+ FD_SET_MAX(0, maxfd, rset);
+
+ do {
+ long next, ticks;
+ struct timeval tv, *ptv;
+
+ if (run_timers(now, &next)) {
+ ticks = next - GETTICKCOUNT();
+ if (ticks <= 0)
+ ticks = 1; /* just in case */
+ tv.tv_sec = ticks / 1000;
+ tv.tv_usec = ticks % 1000 * 1000;
+ ptv = &tv;
+ } else {
+ ptv = NULL;
+ }
+ ret = select(maxfd, &rset, &wset, &xset, ptv);
+ if (ret == 0)
+ now = next;
+ else {
+ long newnow = GETTICKCOUNT();
+ /*
+ * Check to see whether the system clock has
+ * changed massively during the select.
+ */
+ if (newnow - now < 0 || newnow - now > next - now) {
+ /*
+ * If so, look at the elapsed time in the
+ * select and use it to compute a new
+ * tickcount_offset.
+ */
+ long othernow = now + tv.tv_sec * 1000 + tv.tv_usec / 1000;
+ /* So we'd like GETTICKCOUNT to have returned othernow,
+ * but instead it return newnow. Hence ... */
+ tickcount_offset += othernow - newnow;
+ now = othernow;
+ } else {
+ now = newnow;
+ }
+ }
+ } while (ret < 0 && errno != EINTR);
+ } while (ret == 0);