Re: [HACKERS] Moving tablespaces

On Sun, Dec 4, 2011 at 18:07, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
>> On 12/04/2011 11:41 AM, Tom Lane wrote:
>>> Hm, how portable is symlink-reading?  If we can actually do that
>>> without big headaches, then +1.
>
>> I wondered that, specifically about Windows junction points, but we seem
>> to have support for it already in dirmod.c::pgreadlink(). Surely there's
>> no other currently supported platform where it would even be a question?
>
> readlink is required by Single Unix Spec v2 (1997), which is what we've
> been treating as our baseline expectation for Unix-oid platforms for
> awhile now.  Given that we dealt with the Windows side already, I don't
> see a problem with making this assumption.  At worst we'd end up needing
> a couple more emulations in src/port, since surely there's *some* way to
> do it on any platform with symlinks.

AFAICT, it should be as simple as the attached.

Doesn't include the required fixes for pg_upgrade, I'll get on those next.

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/