You should start your Perl program with these two pragmas:

use warnings;
use strict;
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They will help you find mistakes in your code, like why $ofound is not visible at the end of the subroutine.

Had the OP not used strict, and not use my, he wouldn't have had the problem. His problem is the overuse of my, as you point out. Adding either use warning; or use strict; does diddly-squat to solve the problem.