nbpatch looping: No file found--skip this patch? [n]

["Jeremy C. Reed" <reed%reedmedia.net@localhost>]

Using CentOS 5.8 and working on updating botan to latest stable release 
branch.

The patches didn't match up, so nbpatch step said:

No file found--skip this patch? [n] 
File to patch: 

This was repeated continually and Ctrl-C could no kill it and Ctrl-Z 
could not suspend.  Ctrl-S could pause it.  I used pkill nbpatch from a 
different login terminal to stop it.

jreed    12142 16.4  0.0   3872   560 pts/0    S    06:04   0:18 
/usr/pkg/bin/nbpatch -F0 -d 
/home/jreed/pkgsrc/security/botan/work/Botan-1.10.3 --forward --quiet -E 
-p0 -V simple -z .orig

Any ideas about this looping?

I have seen this problem a couple times before, but I don't think I have 
seen it on NetBSD before.