It'd be nice to know how to test this w/o requiring another active P2P peer. That said, I found 10 characters, simply from syntax. If we didn't mind it being like 30 lines long, we could take advantage of newlines for another 15ish characters. 
$p=shift;$a=a(shift);i(shift);socket S,2,1,6;bind S,$a;listen
S,5;undef$/;while(@ARGV&&($_="$p $a f".shift)||accept(C,S)&&($_=<C>)&&
+close
C){m!^(.*?) (.*?) ([e-i])([^/]*)/!s&&$1 eq$p&&&$3($2,$4,$')}sub e{open
F,'>',$_[1];print F $_[2];close F}sub f{t($_,@_)for keys%k}sub
g{open(F,'<',$_[1])&& t($_[0],$a,"e$_[1]",<F>);close F}sub
h{t($_[0],$_,'i')for keys%k}sub i{$k{$_[0]}=1}sub
a{$_[0]=~/:/;pack'CxnC4x8',2,$',split'\.',$`}sub
t{socket X,2,1,6;$w=shift;if(connect X,a($w)){print X
"$p $_[0] $_[1]/$_[2]";close X}else{undef$k{$p}}}

[download]

Update: This is what I just submitted back to the author. I think it ends up being 516 characters over 8 lines. 

$/=$_;$(=shift;$a=shift;i(shift);socket S,2,1,6;bind S,a($a);listen
S,5;while(@ARGV&&($_="$( $a f".shift)||accept(C,S)&&($_=<C>)&&close
C){m!^(.*?) (.*?) ([e-i])([^/]*)/!s&&$(eq$1&&&$3($2,$4,$')}sub f{t($_,
+@_)for
keys%k}sub a{pop=~/:/;pack'CxnC4x8',2,$',split'\.',$`}sub i{$k{$_[0]}=
+1}sub
g{open(F,"<$_[1]")&& t($_[0],$a,"e$_[1]",<F>);close F}sub h{t($_[0],$_
+,'i')for
keys%k}sub t{socket X,2,1,6;if(connect X,a($w=shift)){print X
"$( $_[0] $_[1]/$_[2]";close X}else{undef$k{$w}}}sub
e{open F,">$_[1]";print F $_[2];close F}

[download]

Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.

In reply to Re: P2P Golf: MoleSter by dragonchild
in thread P2P Golf: MoleSter by hossman

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