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[7imz]

so i'm writing this small program where i fork the main program, the i fork the child... so now i essentially have a parent, and two children...

my question is how can i pass the values of the pid's of the children to the parent ?

 

[CrunchyB]

$man fork

On success, the PID of the child process is returned in the parent's thread of execution

 

[7imz]

actullay... i'm not passing the pid of the child...i'm passing a random number calculated based on the pid of the child

 

[Shompola]

Is this an operative system course?

 

[7imz]

software tools and system programming

 

[Shompola]

I see I had a similiar course a few years back. If I remember we had references to the children via the parent with pointers via the datatype.

 

[7imz]

it has somethign to do with WEXITSTATUS... i can't exactly figure it out :s

 

[CrunchyB]

Beej's programming guides helped me through most IPC assignments

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

int main()
{
int pfds[2];
char buf[30];

pipe(pfds);

if (!fork()) {
printf(" CHILD: writing to the pipe\n");
write(pfds[1], "test", 5);
printf(" CHILD: exiting\n");
exit(0);
} else {
printf("PARENT: reading from pipe\n");
read(pfds[0], buf, 5);
printf("PARENT: read \"%s\"\n", buf);
//wait(NULL); (dunno what's up with this >CrunchyB)
}
}