Kovacs Zoltan <kovacsz(at)pc10(dot)radnoti-szeged(dot)sulinet(dot)hu> writes:
> I mean the current pid number of the actual connection. Not the postmaster
> process, I need the pid of the currently running postgres. :-)
I don't believe it's available as a SQL query, but libpq can tell you
what it is.
Probably a more interesting question is "why do you want to know?".
I can't offhand think of a really good reason to use the backend pid
for anything on the client side, other than distinguishing self-notifies
from other notifies, which is not something you can do at the SQL level
anyway.
regards, tom lane