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+<code c>
+/*
+** CPU-bound test
+*/
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <err.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+void runit(double y, int fd, size_t len)
+{
+	double  x;
+	double *bp;
+	size_t i;
+	char	ch;
+	bp = malloc(len);
+	len /= sizeof(double);
+	for (i = 0; i < len; i++)
+	    bp[i] = 1.0;
+	if (write(fd, "x", 1) != 1)
+	    err(1, "write1");
+	if (read(fd, &ch, 1) != 1)
+	    err(1, "read1");
+	i = 0;
+	for (x = 0.0; x < y; x += 1.0) {
+	    bp[i] += x;
+	    if (++i >= len)
+		i = 0;
+	}
+	exit(0);
+}
+int main(int argc, char **argv)
+{
+	double	y;
+	pid_t p;
+	int i, j, x;
+	struct timeval start, end;
+	struct rusage usage;
+	int fds[2];
+	size_t len;
+	char *buf;
+	i = strtol(argv[1], NULL, 0);
+	y = strtod(argv[2], NULL);
+	len = strtoul(argv[3], NULL, 0) * 1024;
+	if (pipe(fds) < 0)
+	    err(1, "pipe");
+	buf = malloc(i);
+	for (j = 0; j < i; j++) {
+		p = fork();
+		if (p < 0)
+			err(1, "fork");
+		else if (p == 0)
+			runit(y, fds[1], len);
+	}
+	for (j = 0; j < i; j++) {
+	    if (read(fds[0], buf, 1) != 1)
+		err(1, "read0");
+	}
+	if (write(fds[0], buf, i) != i)
+	    err(1, "write0");
+	gettimeofday(&start, NULL);
+	while (wait(&x) > 0)
+		;
+	gettimeofday(&end, NULL);
+	getrusage(RUSAGE_CHILDREN, &usage);
+	end.tv_sec -= start.tv_sec;
+	end.tv_usec -= start.tv_usec;
+	if (end.tv_usec < 0) {
+		end.tv_usec += 1000000;
+		end.tv_sec--;
+	}
+	printf("%d %g %ld.%06ld %ld.%06ld %ld.%06ld\n", i, y,
+		end.tv_sec, end.tv_usec,
+		usage.ru_utime.tv_sec, usage.ru_utime.tv_usec,
+		usage.ru_stime.tv_sec, usage.ru_stime.tv_usec);
+	return 0;
+}
+</code>