Question on example found at src/test of libpqxx 3.0

Hello list,

I've started using libpqxx some days ago and had no problem doing the basic
stuff so far... Right now i'm trying to code a simple test program to do
something when it receives a notification from the db. I was looking into
examples provided in the src/test directory of my libpqxx 3.0 installation,
specifically test004.cxx file. There i can see a class named TestListener
wich inherits from class notify_listener. Since i couldn't find the latter
class on the documentation, i assume it doesn't exist and it's just for
demo. Am i correct assuming that? If so, what would this class be? A
trigger? A transactor?
Any directions regarding better understanding of notify/listen would be
appreciated.

Thanx!
--
Matheus Araújo Aguiar
Computer Scientist
matheus(dot)pit(at)gmail(dot)com

=?UTF-8?Q?Matheus_Ara=C3=BAjo_Aguiar?= <matheus(dot)pit(at)gmail(dot)com> writes:
> I've started using libpqxx some days ago and had no problem doing the basic
> stuff so far... Right now i'm trying to code a simple test program to do
> something when it receives a notification from the db. I was looking into
> examples provided in the src/test directory of my libpqxx 3.0 installation,
> specifically test004.cxx file. There i can see a class named TestListener
> wich inherits from class notify_listener. Since i couldn't find the latter
> class on the documentation, i assume it doesn't exist and it's just for
> demo. Am i correct assuming that? If so, what would this class be? A
> trigger? A transactor?

libpqxx isn't part of the core Postgres project, and I'm not at all sure
that its author(s) read this list. You might be best advised to contact
them directly about libpqxx-specific questions. We can tell you about
LISTEN/NOTIFY proper, but not about what sort of C++ wrapper libpqxx
has provided for it ...

regards, tom lane