I suspect you mean 
                if (/^I/) {
                        read_cal(substr($_,1), $mode);
                } else {
                        print "|$_|\n";
                }

[download]
rather than 
                if (/^I/) {
                        read_cal(substr($_,1), $mode);
                }
                print "|$_|\n";

[download]
This is because your $_ variable has been altered by the recursion, so using it is no longer appropriate! If you really want to keep it, you'll have to use a named, local variable.

In reply to Re: Recursive file opening: reading an undef at the end of file by Anonymous Monk
in thread Recursive file opening: reading an undef at the end of file by thor

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