So this one bit me today, and I'm wondering if it's documented anywhere or if I just am missing something in my implementation. I have a sub that sorts some lines based on the IP address at the beginning of the line:

my $fp = \&by_ip;
print $fp->(@input);

sub by_ip
{
    return map { unpack('x4A*') }
        sort
        map { pack('A4A*',inet_aton((split /\s/,$_,2)[0]),$_) } @_;
}

[download]

The output is printed all on one line, which I do not want. I am sure that every line in the input ends with "\n", since this sub is swappable (via assignment to $fp) with several others that do not exhibit this behavior. The only unique thing about this sub is that it uses pack. Does anyone have a clue as to what is going on here? Many thanks.

print pack("A25",pack("V*",map{1919242272+$_}(34481450,-49737472,6228,0,-285028276,6979,-1380265972)))

In reply to pack auto-chomps/chops? by bv

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