After forking, are global variables shared?

Question

Consider this simple code:

 int myvar = 0;
 int main() {
     if (fork()>0) {
       myvar++;
     } else {
       // father do nothing
     }
 }
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Answer 1

fork()ing creates an exact copy of the parent process at the time of forking. However, after the fork() is completed, the child has a completely different existence, and will not report back to the parent.

In other words, no, the parent's global variables will not be altered by changes in the child.