Arno Garrels wrote:
> Francois PIETTE wrote:
>> I've found an interesting multithreading issue which is related not
>> The solution is to rewrite the procedure as follow:
>> Line1: procedure TMyComponent.TriggerMyEvent(MyArg : Integer);
>> Line2: var
>> Line3:     TMyEventProc EventProc;
>> Line4: begin
>> Line5:     EventProc := OnMyEvent;
>> Line6:     if Assigned(EventProc) then
>> Line7:         EventProc(Self, MyArg);
>> Line8: end;
>> Saving the event pointer in line5 make sure that it is still valid in
>> the case a thread switch between Line 6 and 7 occur and the OnMyEvent
>> is set to nil by the other thread.
>> Interesting, isn't it ?
> I think it's better/faster than having critical sections for all
> triggers, do you plan to change all ICS triggers accordingly?

This requires atomic reading/writing of a Pointer (no thread switch
while read/write), I'm not sure whether this is true. Byte variables
are written/read in one go, there's no ploblem.

Arno Garrels [TeamICS]

To unsubscribe or change your settings for TWSocket mailing list
please goto
Visit our website at

Reply via email to