#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#define NTRIES  1000


int main(int argc, char *argv[]) {
    int i;
    long elapsed;
    struct timeval t1,t2;

    gettimeofday(&t1, NULL);
    for (i = 0;  i < NTRIES; i++)
	switch ( fork() ) {
	    case -1: perror("fork"); exit(1);
	    case 0: exit(0); // just exit
	    default: wait(NULL); // wait for child exit
	}
    gettimeofday(&t2, NULL);
    elapsed = ((long)t2.tv_sec - t1.tv_sec) * 1000000L + (t2.tv_usec - t1.tv_usec);
    printf("Elapsed time = %6li us (%g us/call)\n", elapsed, (double)elapsed/NTRIES);
    return 0;
}