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.