Format of SVR4 UUCP lockfiles?

[Emmet P. Gray]

Can someone give me a clue as to the format of the new SVR4 UUCP
lockfiles?  I've figured out the second and third numbers (major and
minor devices numbers), but what is the first number?

Also, what book is this in?  I didn't purchase *all* the SRV4 hardcopy
books, so obviously it's in one I don't have.

Emmet P. Gray				US Army, HQ III Corps & Fort Hood
...!uunet!uiucuxc!fthood!egray		Attn: AFZF-DE-ENV
fthood!egray at uxc.cso.uiuc.edu		Directorate of Engineering & Housing
					Environmental Management Office
					Fort Hood, TX 76544-5057