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ERROR_DELAY_LOAD_FAILED
The Visual C++ linker now supports the delayed loading of DLLs. This relieves you of the need to use the Windows SDK functions LoadLibrary and GetProcAddress to implement DLL delayed loading.
Before Visual C++ 6.0, the only way to load a DLL at run time was by using LoadLibrary and GetProcAddress; the operating system would load the DLL when the executable or DLL using it was loaded.
Beginning with Visual C++ 6.0, when statically linking with a DLL, the linker provides options to delay load the DLL until the program calls a function in that DLL.
An application can delay load a DLL using the /DELAYLOAD (Delay Load Import) linker option with a helper function (default implementation provided by Visual C++). The helper function will load the DLL at run time by calling LoadLibrary and GetProcAddress for you.
You should consider delay loading a DLL if:
- Your program may not call a function in the DLL.
- A function in the DLL may not get called until late in your program's execution.
The delayed loading of a DLL can be specified during the build of either a .EXE or .DLL project. A .DLL project that delays the loading of one or more DLLs should not itself call a delay-loaded entry point in Dllmain.
Bound imports means that in PE-import table store fixed (bound) addresses of import functions for a specific version of DLL with those function. Bound addresses are calculated and written to import table by linker during program compilation and linking phase.
Delayed imports means that in import table instead of import functions addresses contains addresses of a special program part called "delay load helper" (sometimes is called also "thunk"), which substitutes real imported function address when the function is called for the first time. And subsequent function calls use real function address written by delay load helper.