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    <p>Make sure you're calling UnloadPackage for each dynamically loaded package before shutdown. If you're simply calling UnloadLibrary (or simply relying on the OS to unload them), then the finalizations for that the units in that package and all the units from other packages aren't being called. Initializations and finalizations are done using a reference counting system because in the face of dyanmically loaded packages, there is no way to know what units will be initialized and when. Only when you've balanced the finalization calls with the initialization calls will the last finalization call actually execute the code block in the finalization section. Likewise only the first call to the initialization section will actually execute the code block.</p> <p>Initializations/finalizations are done using a compiler-generated table for a given module. When you build an exe or dll linked with packages, this table contains references to all the units that are actually used, even those from the linked packages. Note that <em>only</em> the units actually referenced are actually initialized. IOW, if you have 100 units in PackageA and the exe only references one of them, then only that unit and any units it uses will be initialized.</p> <p>For dynamically loaded packages, there is really no way to know what units will actually be used, so the compiler generates the init/finit table as if every unit were initialized. This table is <em>not</em> processed upon loading of the package during the call to LoadLibrary, but rather is handled by calling a special export called Initialize(). The LoadPackage function ensures that this function is called. This table only ensures that all the units <em>in the loading package</em> are initialized. Only the units <em>actually touched</em> in any other package are initialized, similar to the exe/dll case I mentioned above. UnloadPackge does the reverse, and calls special export Finalize() before calling UnloadLibrary().</p> <p>Finally, if you've made changes to uses lists of any packaged units and only rebuild the package, you can run into confusing cases where initializations/finalizations may not get called even though your units within a given package properly "use" each other. This is because the init/finit is controlled by the <em>loading module</em> and not from within itself. Only in the case where a package is explicitly loaded using LoadPackage will every unit in that package (and that package only) be initialized/finalized.</p>
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    1. POWhy code in any unit finalization section of a package is not executed at shut down?
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    1. USAllen Bauer
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    1. POWhy code in any unit finalization section of a package is not executed at shut down?
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    1. COThank you for your time and detailed explanation. Is it necessary to call UnRegisterModuleClasses() first for any classes that have registered by a dynamically-loaded package?
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    2. COYou should not have to call it, no. Classes will call AddModuleUnloadProc, in order to get unload notifications which will call UnRegisterModuleClasses().
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      1. USAllen Bauer
    3. COJust for interest, I found the line UnloadPackage() commented out for some reason. Scratching in our source archive this was done before 2003, so it has taken at least 8 years for anyone to notice that the finalizations are not run, and only noticed it now because a COM server was not being shut down on app exit.
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