Tom Lane wrote:
The standard approach when using libpq directly is to get the file
descriptor number of the backend connection with PQsocket(), then
include that in the set of FDs that the client app's idle loop
select()s or poll()s on.
And Tino Wildenhain, in off-list mail, described getting the socket-
fd from the PyGreSQL connection object and doing something analogous.
It turns out that Python's listen() takes ints =or= objects with a
fileno() method, whence it gets the int, and PyGreSQL's connection
objects qualify. So I can do this:
import pg, select
con = pg.connect(...)
con.query("listen foo")
while True:
select.select([con], [], []) # Wait for it ...
print con.getnotify()
I wish I could do this with the more "standard" pgdb module, but,
then again, LISTEN/NOTIFY aren't standard. Thanks, Tino and Tom, for
the pointers toward this solution.
- John D. Burger
MITRE
