Networking library

[Cecil Ward]

Can anyone point me in the direction of a library that provides 
very very lightweight (minimum overhead) asynchronous i/o 
routines for - shopping list

1. sending and receiving IPv4 / IPv6 packets,
2. sending receiving ICMP and
3, handling incoming outgoing TCP connections and
4. handling SCTP connections.

Secondingly I am in the market for a library that handles the 
sending and receiving of straight ethernet packets. Also doing 
ARP / NDP too.

Rules of the beauty contest: Some abstraction of asynchronous i/o 
with asynchronous events, but the main priority is being very 
very lean and low-level, with top time-performance. If it comes 
to a beauty contest, this judge I would prefer something C-style 
as I don't speak C++, have yet to drink the mindless class 
bullshit koolaid. Since my background is VAX/VMS asynchronous io 
an asynchronous model with optional callbacks as in VMS or Win NT 
events will win the beauty parade. Operating systems? Cross-o/s 
portability- unsure. Not interested in solutions that are 
synchronous-io-only and so require your code to be split up into 
multiple threads just to get around the problems caused by 
synchronous (‘blocking’ some call it) io calls. Requiring threads 
is a rule-out / show stopper unless I could easily hide such a 
thing, but that doesn't sound feasible.

Any suggestions gratefully received.