I'm not sure whether I understand what you want, but could it be as simple as: 
open my FILE1, "sort -nk2 $input_file |" or die;

[download]
?

(2-arg open, because I can never remember whether I need "|-" or "-|" for 3-arg open; using 2-arg open beats looking it up in the manual).

In reply to Re: Sorting issue by JavaFan
in thread Sorting issue by bluray

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