Talking about xs...

[Roger Burton West]

This strikes me as something that needs a perl module... anyone feeling
particularly bored and like playing with XS?

]librsync (http://freshmeat.net/projects/librsync/)
]  by Martin Pool (http://freshmeat.net/users/bootswork/)
]
]librsync makes the network-delta functions of the popular rsync file
]transfer tool available to other programs. librsync has a streaming
]interface similar to zlib, and is designed to be embedded into diverse
]network applications.

Roger