Documentation is missing that should be there. The "DVI specials Options" page in the handbook says:
KDVI supports a large number of extensions to the original DVI format, e.g. hyperlinks, graphic file inclusion or embedded source file information. These extensions are known as "DVI specials". A full account of specials supported by KDVI can be found in this document.
"This document" is linked to /kdvi/KDVI-features.dvi. Clicking on the link results in
"There is no documentation available for /kdvi/KDVI-features.dvi"