These demos do not use the standard library (not C ++ or even the standard C library), and they are not related to standard libraries (to avoid import table sizes). They dynamically bind only the necessary absolute minimum.
The demonstration "main function" is usually identical to the entry point (unlike a regular program, where the entry point is the CRT initialization function, which performs some configuration on a specific OS, initializes global variables, starts constructors, and ultimately calls main).
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