Log message:

Initial import of bsdiff (and bspatch) version 4.1 into the NetBSD
packages collection as misc/bsdiff.

Bsdiff and bspatch are tools for building and applying patches to binary
files. By using suffix sorting (specifically, Larsson and Sadakane's
qsufsort) and taking advantage of how executable files change, bsdiff
routinely produces binary patches 50-80% smaller than those produced by
Xdelta, and 15% smaller than those produced by .RTPatch (a $2750/seat
commercial patch tool).