Re: advisory locks (was: 8.2 beta blockers)

On 9/17/06, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> We have three possible choices for this: do nothing, install a
> bug-compatible, allegedly-clean-room implementation in contrib:
> http://archives.postgresql.org/pgsql-patches/2006-09/msg00077.php
> or put a hopefully-cleaner design into core, eg per my suggestions here:
> http://archives.postgresql.org/pgsql-hackers/2006-09/msg00467.php
> I favor the third alternative, mainly because by changing the API
> we remove all doubt as to whether any "intellectual property"
> remains from the original GPL'd code.  However, we've got to make up
> our minds and get on with it.

two questions: do we need both a shared and unshared variant of
advisory_unlock (im guessing no)? also, are we exposing the mode in
the int4/int4 signature or are all advisory locks assumed to be
exclusive (if yes, which int4 is the lockmode).

merlin