PIKE_MODULE_INIT/EXIT in a normal pgsql.pike file

I'm almost done rewriting the pgsql driver to be fully callback driven
(it's felt/feels a bit like rebreaking all one's limbs in order to
get better healed bones, painful indeed).

However, in order to get this flying I basically need to run
a separate pgsql backend.  Currently I simply start up a new one in a separate
thread for every connection to the database.
But, these could be shared by all pgsql connections.

So, is there some kind of PIKE_MODULE_INIT/EXIT or C-static equivalent
which I could use to make sure that I only create at most one thread
for this?
-- 
Stephen.