The "test-backlinks" command:
Usage: fossil test-backlinks SRCTYPE SRCID ?OPTIONS? INPUT-FILE Read the content of INPUT-FILE and pass it into the backlink_extract() routine. But instead of adding backlinks to the backlink table, just print them on stdout. SRCID and SRCTYPE are integers. Options: --mtime DATETIME Use an alternative date/time. Defaults to the current date/time. --mimetype TYPE Use an alternative mimetype.