Thread: Multiple processes running concurrently in c

Is this how you do it?

Code:

int main(int argc, char *argv[])
{
        int i = 0;
        for(i=0;i<argc;i++)
        {
                if(fork() == 0)
                {
                        printf("child %d\n", i);
                        exit(1);
                }
        }
        return 0;
}

If not, why not? And how? The key thing I want most if that all the processes run at the same time.

Try it and see! Print out the result of getpid():

Code:

if (fork() == 0) {
    printf("child %d pid %d\n", i, getpid());
    exit(1);
} else {
    printf("pid %d\n", getpid());
}
/*if they're different, you win*/

Although, making as many processes as argc seems next to useless..

Thank you, and the processes to argcs is for a bigger purpose, this was just a test.

Originally Posted by bungkai

Thank you, and the processes to argcs is for a bigger purpose, this was just a test.

Ah okay, cool.

What are you doing, by the way? A lot of the problems that can be solved with fork() can also be solved with threads (with higher control), so, just throwing that out there. In case you're interested:

Linux Tutorial: POSIX Threads
https://computing.llnl.gov/tutorials/pthreads/