need recommendations for b-tree library

[Willis Johnson]

=========== Need b-tree library recommendations ===============

I am writing a program for MS-DOS which needs to build and manipulate a
b-tree of about 400k.  I'd like to keep the program and its data within
the 640k limit, and prefer to avoid disk i/o.  I'll be using Microsoft C.
Any recommendataions for a b-tree library, either free, shareware, or 
commercial, would be greatly appreciated.  If there is much interest, I'll
summarize to the NET.

Thanks,
Willis Johnson
willis at violet.berkeley.edu