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sleep: long sleep

Instead of waking up every second, sleep the maximum
amount possible for long timeouts.

Waking up every second is slow with thousands of
processes hammering the timer.

--- a/sys/src/cmd/sleep.c

+++ b/sys/src/cmd/sleep.c

@@ -4,34 +4,39 @@

 void

 main(int argc, char *argv[])

 {

-	long n;

+	enum { MAXSEC = 0x7fffffff/1000 };

+	long n, m;

 	char *p, *q;

 	if(argc>1){

-		for(n = strtol(argv[1], &p, 0); n > 0; n--)

-			sleep(1000);

+		for(n = strtol(argv[1], &p, 0); n > MAXSEC; n -= MAXSEC)

+			sleep(MAXSEC*1000);

 		/*

 		 * no floating point because it is useful to

 		 * be able to run sleep when bootstrapping

 		 * a machine.

 		 */

-		if(*p++ == '.' && (n = strtol(p, &q, 10)) > 0){

+		if(*p++ == '.' && (m = strtol(p, &q, 10)) > 0){

 			switch(q - p){

 			case 0:

 				break;

 			case 1:

-				n *= 100;

+				m *= 100;

 				break;

 			case 2:

-				n *= 10;

+				m *= 10;

 				break;

 			default:

 				p[3] = 0;

-				n = strtol(p, 0, 10);

+				m = strtol(p, 0, 10);

 				break;

 			}

-			sleep(n);

+		} else {

+			m = 0;

 		}

+		m += n*1000;

+		if(m > 0)

+			sleep(m);

 	}

 	exits(0);

 }