sub openFile {
 my @entries; #is now lexically scoped for the entire subroutine;
  if ($file1) {
    open FH, "$file1" or die $!;
    @entries = <FH>;
    close FH;
  }
  if ($file2)  {
    open FH, "$file2" or die $!;
    @entries = <FH>; #Replace all the entries? what?
    close FH;
  }
}