Question

I need to use shared memory and fork to do this:
Multipling random 512×512 matrixes using 4 processes and shared memory.
I know how to fork one child but
How can I fork 4 processes that do 1/4 of work?

Thanks

Answer 1

ct = 0;
while (ct < 3 && fork() == 0) {
    ct++;
}

ct will tell you which thread you are. You should probably check for a return of -1 from fork(), though.