diff --git a/Makefile b/Makefile
index 1a310eb..417c72a 100644
--- a/Makefile
+++ b/Makefile
@@ -1,2 +1,2 @@
 all:
-	cc -Wall -g -o ctx ctx.c
+	cc -Wall -g -o ctx ctx.c -lrt
diff --git a/ctx.c b/ctx.c
index 765bd39..2bfd111 100644
--- a/ctx.c
+++ b/ctx.c
@@ -66,6 +66,7 @@ struct hip_uctx_t
 	hip_oow_t cso; /* number of context switches out */
 
 	hip_nsecdur_t wakeup_time;
+	int waiting_fd;
 	unsigned int stid;
 
 	hip_uctx_link_t uctx;
@@ -272,10 +273,11 @@ static void multiplex(hip_uctx_t* uctx, void *ctx)
 	hip = uctx->hip;
 	while (1)
 	{
-		if (IS_EMPTY(&hip->sleeping))
+		if (IS_EMPTY(&hip->sleeping) && IS_EMPTY(&hip->io_waiting))
 		{
 // STILL NEED TO HANDLE IO FILE DESCRIPTORS...
 			/* go back to the scheduler */
+printf ("NO SLEEPING. BACK TO SCEDULER\n");
 			swapcontext(&hip->uctx_mux->uc, &hip->uctx_sched->uc);
 		}
 		else
@@ -291,16 +293,28 @@ static void multiplex(hip_uctx_t* uctx, void *ctx)
 			u = UCTX_FROM_LINK(l);
 			now = monotime();
 			wait = now >= u->wakeup_time? 0: u->wakeup_time - now;
-
-printf ("WAITING %llu\n", (unsigned long long)wait);
-			// TODO: support different io multiplexers...
-			tmout.tv_sec = wait / 1000000000;
-			tmout.tv_nsec = wait % 1000000000;
+/* TODO: the io_waiting process that is time-bound must be catered for */
 /* TODO:
  * lazy removal of unneeded context here???
  * 	epoll_ctl(DELETE here
  */
+
+printf ("WAITING %llu\n", (unsigned long long)wait);
+			/* TODO: support different io multiplexers...*/
+		#if defined(HAVE_EPOLL_PWAIT2)
+			tmout.tv_sec = wait / 1000000000;
+			tmout.tv_nsec = wait % 1000000000;
 			n = epoll_pwait2(hip->mux_id, ee, 100, &tmout, HIP_NULL);
+		#else
+			/* epoll_pwait()'s timeout is at the resolution of a millisecond.
+			 * add 1 millisecond as long as there is a fraction of nanoseconds
+			 * less than 1 millisecond.
+			 *  ceil(wait / 1000000.0)
+			 *  (wait / 1000000) + !!(wait % 1000000)
+			 *  (wait + 1000000 - 1) / 1000000
+			 */
+			n = epoll_pwait(hip->mux_id, ee, 100, (wait + 1000000 - 1) / 1000000, HIP_NULL);
+		#endif
 			if (n <= -1)
 			{
 				/* TODO: some error handling action is required */
@@ -312,13 +326,14 @@ printf ("WAITING %llu\n", (unsigned long long)wait);
 				do
 				{
 					l = ee[--n].data.ptr;
-printf ("PWAIT link MULTIPLEX  %p\n", l);
-					/*u = UCTX_FROM_LINK(l);*/
+					u = UCTX_FROM_LINK(l);
 
 					UNCHAIN(l);
 					ADD_BACK(l, &hip->runnables);
 
-					//epoll_ctl(hip->mux_id, EPOLL_CTL_DEL,
+printf ("PWAIT link MULTIPLEX DEL %p fd[%d]\n", l, u->waiting_fd);
+
+epoll_ctl(hip->mux_id, EPOLL_CTL_DEL, u->waiting_fd, HIP_NULL);
 				}
 				while(n > 0);
 			}
@@ -336,7 +351,10 @@ printf ("PWAIT link MULTIPLEX  %p\n", l);
 
 			/* go back to the scheduler */
 			if (!IS_EMPTY(&hip->runnables))
+			{
+printf ("BACK TO SCHEDULER \n");
 				swapcontext(&hip->uctx_mux->uc, &hip->uctx_sched->uc);
+			}
 		}
 	}
 }
@@ -552,13 +570,14 @@ void hip_awaitio(hip_t* hip, int fd, int flags)
 	if (flags & HIP_IO_READ) ev.events |= EPOLLIN;
 	if (flags & HIP_IO_WRITE) ev.events |= EPOLLOUT;
 	ev.data.ptr = hip->running; /* store running context link */
-printf ("PWAIT link ADD  %p\n", ev.data.ptr);
+printf ("PWAIT link ADD  %p fd[%d]\n", ev.data.ptr, fd);
 	epoll_ctl(hip->mux_id, EPOLL_CTL_ADD, fd, &ev);
 	/* TODO: error handling - probably panic? */
 
 	rr = UCTX_FROM_LINK(hip->running);
 	ADD_BACK(hip->running, &hip->io_waiting);
 	hip->running = HIP_NULL;
+	rr->waiting_fd = fd; /* remember the file descriptor being waited on */
 	swapcontext(&rr->uc, &hip->uctx_sched->uc);
 }