cvs commit: src/etc/rc.d root

[Bruce Evans]

On Sun, 4 Dec 2005, Kevin Oberman wrote:

>> Date: Sat, 3 Dec 2005 16:25:28 +0100
>> From: Pawel Jakub Dawidek <pjd at FreeBSD.org>
>> Sender: owner-cvs-all at freebsd.org
>>
>> On Fri, Dec 02, 2005 at 09:33:43PM +0000, Ruslan Ermilov wrote:
>> +> ru          2005-12-02 21:33:43 UTC
>> +>
>> +>   FreeBSD src repository
>> +>
>> +>   Modified files:
>> +>     etc/rc.d             root
>> +>   Log:
>> [...]
>> +>   "-u" no longer causes the transition from RO to RW,
>> +>   now that mount(8) was converted to use nmount(2), so
>> +>   an explicit change to RW is required.  Keep up with
>> +>   this change, and use "-uw" to mount root read-write.

Er, rc.d/root already had the explicit change (it said -u -o rw, not
just -u).

>>
>> I really don't know how we can drop support for '-u'.
>> IMHO this is very widely used and will be a real PITA for users.
>> I also never saw '-uw' before (I always used just '-u').
>>
>> Are you guys also volunteering to fix FreeBSD documentation?:)
>>
>> I really, really do think that this is a very bad idea.

I agree.

> Among the many places this needs to be changed is in the system upgrade
> instructions in /usr/src/UPDATING. I've been typing 'mount -u /' for so
> many years that it will take some time to re-program my neurons,
> too. :-(

I've always used "mount /".  mount(8) knows that "/" is special and
always sets MNT_UPDATE for it.  I think it then gets defaults from
fstab, so "/" gets mounted rw unless fstab says that it is ro.  This
advantage of actually always working, unlike "mount -u /",
"mount -u -o rw /", "mount -u -o noro /" and "mount -uw /", since the
last 4 commands clobber all options that aren't specified on the
command line (the empty set of options on the command line in "mount -u /"
workse by clobbering the ro options).  You have to say something like
"mount -u -o fstab,noro" or "mount -u -o current,noro" to fetch or
preserve when just changing ro to rw.  (It seems to be necessary to use
noro when fstab or current set ro -- rw doesn't seem to cancel ro.)

The implicit -u -ofstab only works for "/".

Bruce