Its a global variable, so use local and set the variable to what you need it to be, as in 
sub firstline {
    use autodie qw/ open /;
    local $/ = "\n";
    open my($fh),'<',$_[0];
    return scalar <$fh>;
}

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In reply to Re: Scope of $/ by Anonymous Monk
in thread Scope of $/ by agarrubio

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