#include <sys/signal.h>
#include <sys/time.h>

int main(int argc, char *argv[])
{
        int pid;
        int i = 0, max = 100000;
        struct timeval tv0, tv1;
        struct timezone tz;
        long diff;

        if (argc >= 2)
                max = atoi(argv[1]);

        signal(SIGCHLD, SIG_IGN);

        gettimeofday(&tv0, &tz);
        while (i++ < max) {
                pid = fork();
                if (pid == 0) {
                        sleep(1);
                        exit (0);
                }
        }
        gettimeofday(&tv1, &tz);

        diff = (tv1.tv_sec - tv0.tv_sec)*1000000 + (tv1.tv_usec - tv0.tv_usec);

        printf("Average per process fork+exit time is %ld usecs [diff=%lu, max=%d].\n", diff/max, diff, max);
        return 0;
}