[DUG] Crystal Reports Crashing the App

[Rohit Gupta]

I suspected that it would not support more than one instance but was 
never able to get an answer from seagatesoftware.

I have also just found a registry entry for v9 to make it threadsafe, 
but it does not match at all with v8.5 that I am using.

I have purchased v11, but am loathe to put in the effort to use this and 
find that the problems remain.  Much better to shift to something else.

As noted, in real life we are not using multiple instances... however 
the crap may well believe that we are.  So I was attempting to trap an 
AV and recover.. but no such luck... the failure is catastrophic.

I hate com objects marginally more than I hate MSs.  :-)  But again, I 
dont want put in the effort and deploy to several 100 sites and found 
out that we have same or other issues.

Robert martin wrote:
> Hi Rohit
>
> It has been some time since I used the Crpe method of accessing 
> Crystal but my understanding is it is not Thread safe and therefore if 
> you use it in threads or try running multiple copies of reports it can 
> go bang.  This may be what you are experiencing.
>
> In the end w gave up on Crpe and now use the Com object to run them.  
> This works better but comes with other issues.  I think it is the 
> better access method though.
>
> Not a log of help i'm afraid :)
>
> Rob Martin
> Software Engineer
>
> phone +64 03 377 0495
> fax   +64 03 377 0496
> web www.chreos.com
>
> Wild Software Ltd
>
>
>
> Rohit Gupta wrote:
>> In our real app, the program crashes randomly (regularly for some 
>> users) at the instance that Crpe is used.  The app basically 
>> disappears which implies that substantial code and/or stack is 
>> corrupted.
>>
>> In a smaller app that only opens the report to get some stats (it 
>> does not connect to the database), I can get it to crash in the same 
>> fashion predictably.
>>
>> The sequence of events is open two copies of the app )or one copy of 
>> the app and the CRW designer)
>> Open any report in the first app (which always assignes ReportName to 
>> blank and does not destroy the crpe component
>> Open any report in the second app or CRW Designer
>> Open any report in the first app and its gone with no trace.
>>
>> In real life the users can not run multiple copies, the app takes 
>> care of that.  However the symptoms are identical leading me to 
>> believe that if I can find the cause of the second crash, I can fix 
>> the first one.
>>
>> Any clues anyone ?
>> I cant find anything pertinent on google, except for one item where 
>> the author insists that the problem is a secret com object that crpe 
>> launches and if you wait for it to finish and terminate then there 
>> are no crashes.  However, delays dont have any effect on my test case.
>>
>> In the debugger, if I keep doing F7, everything keeps working.  But 
>> as soon as I press F8 or F9, it gets an AV because it starts 
>> executing in hyperspace.
>>
>> _______________________________________________
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>> Delphi at ns3.123.net.nz
>> http://ns3.123.co.nz/mailman/listinfo/delphi
>>
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