FYI. Apologies if duplicated.

Begin forwarded message:

> From: Jeff Johnson <n3npq@mac.com>
> Date: December 1, 2009 10:51:15 AM EST
> To: rpm-devel@rpm5.org
> Subject: Adding bsdiff/bspatch executables to rpmio
> 
> While doing due diligence wrto Courgette, I eventually
> ended up reading the PhD thesis and looking at code here:
> 
> 	http://www.daemonology.net/bsdiff/
> 
> The bsdiff/bspatch utilities are teensy (and likely not widely deployed in linux),
> so I'll likely add to rpmio and do the usual "stuff" to use Fopen(3) et al before
> splitting out some -lrpmio object API and moving what remains of bspatch/bsdiff
> to tools/* for installation in /usr/lib/rpm/bin.
> 
> Dunno whether bsdiff is useful, mho currently tells me that binary
> patching has two fatal flaws fundamentally at odds with "package management"
> 
> 	1) the before <-> after references must coexist on some machine
> 	(not true for rdiff from librsync and afaik for zsync)
> 
> 	2) there's a combinatorial failure juggling all possible deltas
> 	that will never ever scale no matter how small the binary deltas
> 	are.
> 
> 73 de Jeff