While I am using Visual Studio 2008, there is an warning of this content:

warning C4996: ‘fopen’: This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.

There is also this kind of warnings when you are using sprintf etc.. We can use preprocessor _CRT_SECURE_NO_WARNINGS to shutdown this warning.