SK is a Macintosh implementation of BSD style TCP and UDP sockets that also provides some Unix calls missing from the Mac. It is intended to aid in the porting of Unix software to the Macintosh line of computers.
SK is actually a slightly altered/enhanced port of Matthias Neeracher's GUSI (Grand Unified Sockets Interface) that is intended to work with the Symantec C++ 7.x compiler. GUSI implements more types of socket domains than does SK but it currently runs only under MPW and (soon) Metrowerks CodeWarrior. SK on the other hand, currently runs only under Symantec C++ 7.x.
This is also available via anonymous ftp at: dsg.harvard.edu in the directory: /pub/src/SK