There are several ways to force a re-link of a document or library.
To re-link a particular document, or set of documents, from scratch, their index files may simply be removed, using a command such as:
rm *.htx/htx.index
The linker will then re-generate these indices and consider the affected documents to have changed. They, and all other documents that refer to them, will then be re-linked as necessary. Alternatively, to re-link all documents from scratch in this way, the -a flag may be given on the hlink command line.
Removing the "htx.log" date-stamp file from a document library will also force the documents in that library to be re-linked but without unnecessarily re-generating any of its index files. This can be somewhat faster if the index files are known to be up to date.