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  Link-Editing

The linker identifies those documents that have changed since the library they reside in was last linked by looking for a file called "htx.log" which serves as a date-stamp in each document library (if this file is absent, all documents in the library are considered changed). The contents of the "htx.log" file also list the location of each local document when the library was last re-linked. Any that have moved to a different location are also regarded as "changed".

The linker identifies all other documents which refer to any of the changed documents. Since all of these are potentially involved in cross-references that may no longer be valid, they will all need to be re-linked.

A further search is then made of the libraries that appear on the HTX_PATH search path. If any of the documents that needs re-linking refers to a document on this path, then the latter document's index file is searched to identify the HTML file that is being referenced.

Finally, the affected HTML files are edited to insert the new, correct URLs. After this, any WWW browser should be able to follow any of the links between the documents and arrive at the correct location.

A document set will need linking again whenever a document is added or removed, or whenever one of its documents changes. However, because the linker can quickly identify which files are affected and can utilise existing index file information, subsequent linking operations are much faster.



next up previous
Next: Absolute and Relative Links
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HTX Hypertext Cross-Reference Utilities
Starlink User Note 188
R.F. Warren-Smith
6th January 1998
E-mail:rfws@star.rl.ac.uk