How to read the value of a registry key in C

#define BUFFER 8192

int main()
{
	char value[255];
	DWORD BufferSize = BUFFER;
	RegGetValue(HKEY_LOCAL_MACHINE, "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion", "SystemRoot", RRF_RT_ANY, NULL, (PVOID)&value, &BufferSize);
	std::cout << value << std::endl;
	system("pause");