Hi,

My DBak application works by extracting metadata information
from system tables. In some cases it seemed to be causing the
the v1.5.2 server (Windows Superserver under WinXP) to abort
with the following messages:


HOMER (Server) Sun May 15 23:10:11 2005
Exception occurred in system provided internal filters for
filtering internal subtype 2 to text. Access violation.
The code attempted to access a virtual
address without privilege to do so.
This exception will cause the Firebird server
to terminate abnormally.

HOMER (Client) Sun May 15 23:10:11 2005
C:\Develop\FB152\bin\fbserver.exe: terminated abnormally
(3221225477)


I had not noticed this in earlier FB releases (but did not use
v1.5.1 for long so it may have existed there). The problem
only occurs with DBak restore or rebuild because...

I tracked down the problem to the fact that DBak was reading
the BLR fields during restore and rebuild operations. At this
time I do not use the BLR anyway, so I stopped DBak from
reading the BLR and my problem has gone away - and DBak has
probably gotten a bit faster as a result.

But this does raise the question of why the server should abort
when filtering BLR fields. Note that the server aborts are
inconsistent (do not occur on same procedure BLR every time).


Because of the inconsistency of the problem it is difficult to
produce a reliable test case. In theory reading BLR fields as
text from any database containing many procedures should see
the problem - at least some of the time.

Does anyone have any thoughts on this issue. I may want to be
able to read BLR in the future (to decode it so that DBak can
handle databases without source).


Is anyone else seeing this problem (with DBak or any other
application) ?


--
Geoff Worboys
Telesis Computing