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Cc: freebsd-hackers@freebsd.org, m.e.sanliturk@gmail.com, avg@freebsd.org,
	freebsd-arch@freebsd.org
Subject: Re: looking for error codes
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On Apr 2, 2011, at 1:50 AM, perryh@pluto.rain.com wrote:
>=20
>> With respect to my knowledge , no one of the operating systems
>> has a facility to separate read-only and modifiable parts ...
>=20
> SunOS 4 had a partial solution to this, by rearranging the FS layout
> so that /usr could be mounted read-only (and often, from a server --
> IIRC a single /usr could be shared among multiple diskless clients).
> They used quite a few symlinks so that things could be found in
> their accustomed places although actually located elsewhere.  The
> scheme was fairly well described in the SunOS 4 manual set; granted
> _finding_ a SunOS 4 manual set these days may be a challenge :)

FreeBSD can do this too.  In fact, NanoBSD relies heavily on having most =
of the system mounted read-only, and has MFS partitions for /etc and =
/var.

Warner