Untested: 
use List::Util qw(max);
my @lines = split /\n/, $str;
my $prefix  = join "\n", @lines[0..@lines-16];
my $postfix = join "\n", @lines[max(0, @lines-15)..$#lines];

[download]

(Update: fixed offby1 error)

In reply to Re: Split a variable at a Given Line-Number by moritz
in thread Split a variable at a Given Line-Number by danj35

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