父进程根据退出状态监控和派生新的子进程

Question

I've created the below code:

int main(int argc, char *argv[])
{
        int i, n, N;
        pid_t pid;
        int status;

        N = atoi(argv[1]);

        for(i = 0; i < N; i++) {
                pid = fork();
                if(pid==0) {
                        srand(getpid() * getppid());
                        n = rand() % 10 + 1;
                        printf("I'm child nº %d with childpid %d, parent pid = %d, n = %d\n", i, getpid(), getppid(), n);
                        exit(n);
                }
        }

        while ((pid = waitpid(pid, &status, 0))) {
                if (pid < 0)
                        ;
                else if (WEXITSTATUS(status) < 4)
                        printf("exit status %d lower than 4\n", WEXITSTATUS(status));
        }
        wait(NULL);
        return 0;
}

The idea is a parent process forking N child process and each of them exiting with a random value. I want my parent process to monitor all the child processes and fork a new child if the exit status is, for instance <4. This will be going on until all process exit with a status >= 4.

Answer 1

Solved creating a function copying the code from parent and child (keeping the code in main() untouched). The parent calls the function, the function forks another process, and the parent in the same function calls the function recursively under the conditions we choose.