Thread: Forking advice

Hi guys and girls,

I am working on a program that uses forking.

I understand that when u fork, the current process is cloned and the parent and child process start at the next line after the fork process.

So i want to make 2 child processes. I mean I want to spawn one child that will generate a random number and will return with that exit code and another child that does the same.

But i cant fork from inside the first fork rite cuz that would make the second child a child of the first child which is the child of the parent.

So i have to fork AFTER the first child exits rite?

so that the second is a child of the parent as well.

cant paste my code cuz its on a unix console but i will write it out.

Code:

// proper includes...

int main{
  int result1 =-1, int result2=-2;

  pid_t pid;

  // first child spawned
  pid = fork()

  if pid == 0
    result1 = player();
    exit(result1);

  pid = fork()

  if pid == 0
    result2 = player();
    exit(result2);

}

int player{
   srand(10);

   // returns 1 or 0
   int i= rand()%1
   return i;
   }

Am getting wierd numbers, i dont want a solution just guide me on how to properly use fork, exit, and wait

thank you very much

Another question:

look at this simple code

Code:

#include<stdio.h>
#include<sys/types.h>
#include<unistd.h>

int main(){
	int pid,status;
	switch (pid = fork()) {
		case 0:  /* child process */
			printf("Hello I am the child running :D, and my pid is: %d\n",getpid());
			exit(1);
			break;
		case -1: /* parent process -- fork() was unsuccessful, no child */
			printf("Fork failed!");
			break;
		default: /* parent process -- successful */
			printf("Hello I am the parent, the big boss and my pid is: %d\nI am waiting for my child to return...\n",getpid());
			pid_t rpid = wait(&status);		
			printf("We got a child returning with code: %i , and pid : %d !\n",status, rpid);
			break;
	}
}

i get output:

Code:

Hello I am the child running :D, and my pid is: 26860
Hello I am the parent, the big boss and my pid is: 26859
I am waiting for my child to return...
We got a child returning with code: 256 , and pid : 26860 !

Why is the value of status 256?
i sent an exit code of 1 ...

( cnat look up the api my man is busted on this system