>The manual pages reference mount_lofs(1), though it does not exist.
>Has it been removed from the system?  A quick grep of the source tree
>shows many references to it.  I assume it was removed because it
>duplicated the functionality of nullfs.

Define "many."  The only references I was able to find were in
mount_union(8) and mount_umap(8).
-- 
Mike Long <mike.long@analog.com>           http://www.shore.net/~mikel
VLSI Design Engineer         finger mikel@shore.net for PGP public key
Analog Devices, CPD Division          CCBF225E7D3F7ECB2C8F7ABB15D9BE7B
Norwood, MA 02062 USA                assert(*this!=opinionof(Analog));