Re: PQtrace doesn't work

Daniel Verite wrote:
>     Bruce Momjian wrote:
>
> > Looking at the code, the only thing I see done by PQtrace are some calls
> > to fprintf to that file descriptor, like this:
> >
> >     fe-misc.c:  fprintf(conn->Pfdebug, libpq_gettext("To backend> Msg %c\n"),
> >
> > Hard to imagine what would fail there, unless libpq_gettext() doesn't
> > work, but you are probably not use NLS, so it would be a noop:
> >
> >     #define libpq_gettext(x) (x)
> >
> > Can you send us a backtrace of the failure from VC++?  We don't have too
> > many internals guys using that setup, but the backtrace should suggest a
> > cause.
>
> Having a similar setup, I've tried enabling PQtrace and it also crashes
> for me, apparently as soon as libpq tries to write into the stream.
>
> In the hope of debugging at the point of the fprintf call,
> I've built a libpq.lib to link with, as opposed to libpqdll.lib,
> but the statically-linked version doesn't crash, it works as
> expected.
>
> So it looks like the problem would be DLL-related?

Is there a problem with a DLL writing to a file descriptor opened by
application code?  I would think not, but perhaps.

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