RE: libpq debug log

From: 'Alvaro Herrera' <alvherre(at)alvh(dot)no-ip(dot)org>
> > (41)
> > +void
> > +PQtraceEx(PGconn *conn, FILE *debug_port, int flags)
> > +{
>
> I'm not really sure about making this a separate API call. We could just
> make it PQtrace() and increment the libpq so version. I don't think
> it's a big deal, frankly.

If we change the function signature, we have to bump the so major version and thus soname. The libpq's current so major version is 5, which hasn't been changed since 2006. I'm hesitant to change it for this feature. If you think we can bump the version to 6, I think we can go.

https://tldp.org/HOWTO/Program-Library-HOWTO/shared-libraries.html
--------------------------------------------------
try to make sure that your libraries are either backwards-compatible or that you've incremented the version number in the soname every time you make an incompatible change.

When a new version of a library is binary-incompatible with the old one the soname needs to change. In C, there are four basic reasons that a library would cease to be binary compatible:

1. The behavior of a function changes so that it no longer meets its original specification,

2. Exported data items change (exception: adding optional items to the ends of structures is okay, as long as those structures are only allocated within the library).

3. An exported function is removed.

4. The interface of an exported function changes.
--------------------------------------------------

Regards
Takayuki Tsunakawa