On Mon, 18 Dec 1995, Christos Zoulas wrote:

> I make /usr/obj a symbolic link that points to different places on
> different machines, and then change BSDOBJDIR in bsd.own.mk.

I do the same, and throw in a dose of OBJMACHINE for good luck.  I have 
no problem building multiple architectures out of one source tree, and I 
only need to update the obj* links occasionally (as sup adds or removes 
directories).

Union mounts seem like a reasonable solution for those folks with source 
on an inherently read-only medium; if they're broken for this case, they 
should be fixed.  I've yet to hear of problems with union mounting a 
local filesystem over a CD-ROM, though.

--scott