Yes, Perl closes open file handles when the program exits. That is the final point at which things can go out of scope.

The real advantage of storing file handles in variables is that you don't accidentally share a file handle. With global handles, this could be a problem. By using my, the variable is limited in scope.

Even though file handles in my variables close when their scopes end, it's considered good form to manually close the handle (and check the return status). Just because Perl could do something for you doesn't mean you should let it.

Phil