diff --git a/lib/libc_r/uthread/uthread_kevent.c b/lib/libc_r/uthread/uthread_kevent.c
index a7dfbf0003cb..17aeaea4583e 100644
--- a/lib/libc_r/uthread/uthread_kevent.c
+++ b/lib/libc_r/uthread/uthread_kevent.c
@@ -49,7 +49,7 @@ _kevent(int kq, const struct kevent *changelist, int nchanges,
 
 	rc = __sys_kevent(kq, changelist, nchanges,
 	    eventlist, nevents, &nullts);
-	if (rc == 0 && (timeout == NULL ||
+	if (rc == 0 && eventlist != NULL && nevents > 0 && (timeout == NULL ||
 	    timeout->tv_sec != 0 || timeout->tv_nsec != 0)) {
 		/* Save the socket file descriptor: */
 		curthread->data.fd.fd = kq;