Re: [BUGS] Patch to allow C extension modules to initialize/finish

On Thu, Aug 03, 2006 at 05:30:48PM -0400, Tom Lane wrote:
> "Ralf S. Engelschall" <rse@engelschall.com> writes:
> > Hence I propose the patch below (applies to PostgreSQL 8.1.4)
> > which mimics the dlopen(3) and dlclose(3) behaviour of some Unix
> > platforms and resolves and calls _PG_init and _PG_fini functions
> > of an extension module right after/before the pg_dlopen/pg_dlclose
> > calls in the FMGR.
> 
> This seems like a reasonably good idea, and we have got uses for at
> least the "init" case in most or all of our PLs.  It's nominally too
> late for 8.2 feature freeze, but I said just a couple days ago that
> we shouldn't take a very hard line on that.  Does anyone object to
> considering this for 8.2?

Nope :)

> One question I have is whether it really works as expected in all
> cases.  In particular what if the library is "preloaded" into the
> postmaster?  Both plpgsql and plperl seem to think they might need
> to make a distinction between things to do at library load time and
> things to do per-backend ... and yet, neither of them *actually*
> have anything they need to do per-backend.

I'm not sure quite what you mean here, but PL/PerlU functions can
use() modules, and those are called per-backend, i.e. when the
function is invoked.  There's also some possibility that something
might go into %_SHARED.

Cheers,
D
-- 
David Fetter <david@fetter.org> http://fetter.org/
phone: +1 415 235 3778        AIM: dfetter666                             Skype: davidfetter

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