DragonFlyBSD

#include <stdio.h>

#include <stdlib.h>

#include <sys/types.h>

#include <sys/mman.h>

int

main(int argc, char *argv[])

{

        void *ptr;

        pid_t pid;

        size_t amt;

        int wstat;

        amt=(size_t) (1 * sizeof(char));

        ptr = malloc(amt);

        printf("pre-lock: %p\n", ptr);

        mlock(ptr,amt); 

        if((pid = fork()) == 0) {

                sleep(1);

                printf("child: %p\n", ptr);

                return 0;

        }

        else {

                printf("parent: %p\n", ptr);

                waitpid(pid, &wstat);

        }

        return 0;

}