#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>


int main(int argc, char **argv) {
    printf("before fork my pid %d\n", getpid());
    pid_t childpid = fork();
    if (childpid == -1)
        perror("fork"), exit(0);

    if (childpid == 0) {
        printf("child: my pid %d, my parent's pid is %d\n", getpid(), getppid());
        //raise(SIGKILL);
        //void *n = *(void **)NULL;
        return 42;
    } else {
        for (int i = 0; i < 2; i++) {
            //printf("parent: my pid %d, my child's pid is %d\n", getpid(), childpid);
            int status;
            pid_t childexited = wait(&status);
            if (childexited == -1) {
                perror("wait");
                continue;
            }
                
            if (WIFEXITED(status)) {
                printf("parent: my normally exiting child is %d, with %d\n", childexited, WEXITSTATUS(status));
            } else if (WIFSIGNALED(status)) {
                printf("parent: my crashed or signalled child is %d, with %d\n", childexited, WTERMSIG(status));
            } else {
                printf("something else\n");
            }
        }
        
    }
}