Constant includes information whether osOpenStreamfunction is included or excluded during compilation. The function will be compiled if constant value is 1 and will not be compiled when the value is 0.

When the constant is not defined, the loaded value is 1 and the function is stored in the output code. If all of the osOpen* functions are not used, the system will ignore object names and code used for name management will be removed. It will reduce final size of the output code. For more information about the names and object opening see the system objects management section.

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