how do people play with different versions of DBSD on the same system?

[Bill Hacker]

Bob Bagwill wrote:

On Sat, 24 Sep 2005 06:30:49 -0400, Erik Wikström 
<erik-wikstrom at xxxxxxxxx> wrote:

When superVFS is in place, would we be able to have a /release,
/preview, /development, and mount them over / at boot-time?


Would it not be easier to install one instance of each and use the same
/home for all of them, that would probably work even for multiple BSDs.

Sometimes.

But mail services, to name one, often use /home, and never for 100% of 
what they read and write.

Best if each OS install is fully self-contained, shares only 'non-OS 
sensitive' app/data storage.

True of CP/M 1.X & 2X, MPM, CCP/M, DOS, OS/2, and so on as well...... ;-)

Give 'em their own toybox.

My impression is (correct me if I'm wrong) that the main differences 
between
DEVELOPMENT, PREVIEW, and RELEASE are in the kernel, libraries, and 
toolchain,
in that order.  Userland changes are pretty minor. Having to download, 
build,
rebuild, configure, reconfigure the other 95% is a pain.
Perhaps so, but a highly 'automated' pain.  Start the cvsup and make 
scripts, go relax.

The alternative is too often trying to locate what unexpectedly changed 
off in some seldom-visited corner...
and will change again, differently, next cycle.

Any 'modern' OS is too big to keep the whole thing in view, and space is 
cheap.

YMMV,

Bill Hacker