🚀 go-pugleaf

In article <2914@media03.UUCP>, rla@media03.UUCP (Raymond van der Laan) writes:
|> Is this possible in a DLL:
|> 
|>     ... x;
|>     ... y;
|> 
|>     f1 ()
|>     {
|>         y = GlobalAlloc(...);
|>         x = GlobalLock(y);
|>         PeekMessage()
|>         if ours then memcpy(x,...,...);
|>         else Translate & DispatchMessage
|>         ...
|>     }
|> 
|>     f2 (a)
|>     {
|>         memcpy(a, x, ...);
|>         GlobalFree(y);      <-------------\
|>     }                                     |
|>                                           |
|> The caller calls f1, then f2.             |
                                             |
Yes, but some considerations:                |
                                             |
  - Don't forget the GlobalUnlock().  -------/

  - If x and y are global variables for the DLL then f1() and f2() are
    not reentrant.  Consider what happens if you have two applications
    using your DLL and the translate/dispatch within f1() for app1 causes
    app2 to call f1().

    This is probably not a concern for you, but if it is then you will
    want to take some steps to either prevent reentrancy, provide
    some form of mutual exclusion in f1() and f2(), or allow x and y
    to be instance variables for each application using the DLL.

  - The above example is clear enough in what it does, but not at all
    clear is why you are considering this.  What is happening in your
    application that requires this functionality in a DLL?



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