There's no null in Perl. Oddly enough, undef sets the value to: undef.

Minimize the area in which you change $/ by using local. It even has the fortunate side effect of setting the localised variable to undef. 

{
    local $/;
    ... $/ is undef here ...
}
... $/ is restored here ...

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In reply to Re: undef $/ to null by ikegami
in thread undef $/ to null by Selvakumar

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