Il 10/02/2016 08:44, zeljko ha scritto:
1.Your ErrList access does not look thread safe.
It's a poor man's thread safe queue, implemented as a ring buffer, with two indexes, ErrGet and ErrPut. It's fully safe, provided the buffer is guaranteed not to overflow, and that ErrPut is updated only after the buffer has been written. Only the sending thread writes the buffer and ErrPut, while the receiving thread only writes ErrGet, and reads just once ErrPut. This mechanism has been tested by some billion messages passing in the years through it, by Kylix applications running 7/7 24h/24h in several hundreds locations.
It's not that there have been billions if errors:-) , but an identical setup is used to update informations at a rate of 8/10 per second. Only, in Kylix I couldn't use PostMessage, and it was processed in an OnIdle handler.
2.You are casting postMessage param as integer, IMO it's wrong, shouldn't it be PtrInt or LPARAM ? PostMessage(Form1.Handle,LM_ERROR, LPARAM(ErrPut),0);
PostMessage param is not actually used.
3.Application.ProcessMessages probably recurse.
This I believe to be the problem. From the observations from Denis I realized that my code isn't protected against recursion, but I believe that Application.ProcessMessages should protect itself too, avoiding to handle more than once the same message.
However thanks a lot, Giuliano -- _______________________________________________ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
