Various firms use the Microsoft HXS format for compressing help files to support their products. I wish to enable users with licensed copies of HXS help files to index and search their content using my "Words Close Together" search engine. There are suggestions in the literature that Microsoft is using a standard form of compression for HXS.
 Is the compression method open?
 Does C or C++ public domain source code exist that would permit me to embed extraction capability in my indexing software?
 Where can I get such source code?