track.
The $Id$ line is normally at the bottom of the main comment block in the
man page, separated from the rest of the manpage by an empty comment,
like so;
.\" $Id$
.\"
If the immediately preceding comment is a @(#) format ID marker than the
the $Id$ will line up underneath it with no intervening blank lines.
Otherwise, an additional blank line is inserted.
Approved by: bde
in the main text of various man pages.
Thanks to Warner Losh for adding an option to manck to allow
it to scan the entire man page looking for bogus xrefs, instead
of just checking the SEE ALSO section.
