confirm that csup is still usable fos the new 9.1

[Ben Morrow]

Quoth Chris Rees <utisoft at gmail.com>:
> On 26 Nov 2012 08:12, "Perry Hutchison" <perryh at pluto.rain.com> wrote:
> > Kevin Oberman <kob6558 at gmail.com> wrote:
> >
> > > ... don't bet that csup and cvs will be around long ...
> > > It's really time to get away from CVS and I suspect
> > > it will be going away sooner than had been planned.
> >
> > Once csup goes away, how will a base-only system update
> > the sources, e.g. to follow a security branch?
> 
> freebsd-update will update your sources for you.

It would be convenient if, before csup disappears, the 'Sychronising
your Source' section in the Handbook could be updated to contain
instructions for updating *just the source* using freebsd-update. Even
if this is as simple as 'Components src' it would be good to state that
explicitly; it would also be useful to give a procedure for moving from
a csupped tree to one which freebsd-update will be able to apply deltas
to, if that's possible without redownloading the whole source tree.

In general, it's not terribly clear to me what will happen if I run
freebsd-update on a system I have built from source. How does it know
where to start from when it downloads deltas: does it assume `uname -r`
accurately reflects the exact current state of the system? What will
happen if I patch my source and then run freebsd-update without
reverting those changes: will it revert them for me, like csup did, will
it make a mess, or will the update fail?

It would also be better, IMHO, to change the language in that section to
recommend freebsd-update for those running RELEASE branches, and reserve
the svn recommendation for those tracking development branches.

Ben