Various additions and fixes.

src/lib9/sleep.c

@@ -0,0 +1,35 @@
+#include <u.h>
+#define NOPLAN9DEFINES
+#include <libc.h>
+#include <sys/time.h>
+#include <sched.h>
+
+int
+p9sleep(long milli)
+{
+	struct timeval tv;
+
+	if(milli == 0){
+		sched_yield();
+		return 0;
+	}
+
+	tv.tv_sec = milli/1000;
+	tv.tv_usec = (milli%1000)*1000;
+	return select(0, 0, 0, 0, &tv);
+}
+
+long
+p9alarm(ulong milli)
+{
+	struct itimerval itv;
+	struct itimerval oitv;
+
+	itv.it_interval.tv_sec = 0;
+	itv.it_interval.tv_usec = 0;
+	itv.it_value.tv_sec = milli/1000;
+	itv.it_value.tv_usec = (milli%1000)*1000;
+	if(setitimer(ITIMER_REAL, &itv, &oitv) < 0)
+		return -1;
+	return oitv.it_value.tv_sec*1000+oitv.it_value.tv_usec/1000;
+}