--- In firebird-support@yahoogroups.com, "certfb" wrote:

>
> Hello list!
>
> I have implemented a very simple GUI version of the bundled trace tool fbtracemgr using wxWidgets.
>
> If anyone is interested I am more than happy to upload or send them the code.
>
> If I get the chance I will try to write a blog because some aspects of the trace API take a bit of digging to find the documentation ;)
>
> The only problem that I have at the moment is that I am using the "isc_info_svc_timeout" command as part of a "isc_info_svc_line" isc_service_query() but instead of replying with "isc_info_svc_timeout" in the header the server replies with "isc_info_svc_line" but a zero length data block.

IIRC, isc_info_svc_line (or isc_info_svc_to_eof) + zero data length means end of stream and service was stopped at server side.

BTW, fbtracemgr used isc_info_svc_to_eof query, not isc_info_svc_line. The latter will produce very low performance.

> I looked through the source of fbtracemgr and although I think it expects "isc_info_svc_timeout" it probably doesn't give an error if it doesn't get it.

Because it is not an error. Errors reported via status-vector :)

> It isn't particularly important because I can just detect 0 length lines (for a normal response even an empty line provides a '\n') but I wondered if anyone has any ideas about this?
>

Re-read TraceSvcUtil::runService() carefully...

Regards,
Vlad