其实是简单的:
#define KEY_ITEM_TEST SOFTWARE
#define KEY_VALUE path
if (ERROR_SUCCESS ::RegOpenKeyExA(HEKY_LOCAL_MACHINE, KEY_ITEM_TEST, 0,KEY_READ, hKeyResult))
::RegQueryValueExA(hKeyResult, KEY_VALUE, 0, &dwDataType, NULL, &dwSize);
::RegQueryValueExA(hKeyResult, KEY_VALUE, 0, &dwDataType, pBuffer, &dwSize);