Server Message filter for _servermsg_cb

Hello,
I have recently encountered a problem while trying to backup
database.
_servermsg_cb raises error on messages that are not error for
backup.
Maybe I missed something.
I failed to work around this problem without changing
_servermsg_cb :

#====================================================================
def _servermsg_cb(ctx, conn, msg):
    skiperr = False
    hook = _output_hooks.get(conn)
    if hook:
        skiperr = hook(conn, msg)
    if skiperr: return

    mn = msg.msgnumber
    if mn == 2601: ## Attempt to insert duplicate key row in
object with unique index
        raise IntegrityError(msg)
    if mn == 2812: ## Procedure not found
        raise StoredProcedureError(msg)
    if not (mn in (0, 5701, 5703, 5704) or ((mn >= 6200) and (mn
< 6300))):
        # Non-errors:
        #    0      PRINT
        # 5701      Changed db context
        # 5703      Changed language
        # 5704      Changed character set (Sybase)
        # 6200-6299 SHOWPLAN output (Sybase)
        raise DatabaseError(msg)
#====================================================================

Then I specified in hook messages that I consider not errors
returning True.
If I am wrong and there is a simpler way to solve the problem
please help me.

Alexander Stepochkin,
IT Department,
Troika Dialog, Moscow, Russia
+7 495 258-05-00 ext. 1311



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