Actually argument passing isn't the problem in your code. Since you define $value in a file scope, it's visible to your subroutine w/o being passed.

If I may draw your attention to something else? 

chomp ($input = <STDIN>);
$input = $value; # <--- are we sure about this?!?
#call subroutine to check user input
verification($value)

[download]

If I may suggest $value = $input?

In reply to Re: Passing a scalar to a subroutine by Anonymous Monk
in thread Passing a scalar to a subroutine by rspishock

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