Re: Client application name

Dave Page <dpage@pgadmin.org> writes:
> I just realised there's a nasty problem with this. In my client
> application, I can use PQconninfoParse to determine if
> application_name (or fallback_application_name) are valid connection
> string options for the version of libpq that I have.

> However, there is no way that I can see of doing a comparable test in
> libpq itself, to ensure that the server understands the parameter, so
> if I connect to an 8.5 server, everything works fine, but if connect
> to an older server with my new libpq, the connection fails because of
> the unknown parameter in the startup packet.

Hmm, yeah, that's a good point.  It seems like you will have to send the
appname SET command as a separate packet, after you have gotten the
initial response and know what version the server is.  Kind of annoying
from a performance standpoint, but I believe it won't be too hard to
shoehorn into libpq --- it already has a code path for that for older
servers, IIRC.
        regards, tom lane