Call this method to retrieve the string data for a specified value name.
If the method succeeds, ERROR_SUCCESS is returned. If the method fails to read a value, it returns a nonzero error code defined in WINERROR.H. If the data referenced is not of type REG_SZ, ERROR_INVALID_DATA is returned. If the method returns ERROR_MORE_DATA, pnChars equals zero, not the required buffer size in bytes.
This method makes use of RegQueryValueEx and confirms that the correct type of data is returned. See RegQueryValueEx for more details.
This method allows the caller to specify any registry location, potentially reading data which cannot be trusted. Also, the RegQueryValueEx function used by this method does not explicitly handle strings which are NULL terminated. Both conditions should be checked for by the calling code.