high order-low order是什么意思?
在GetFilesize的remark中有如下一段
If the function succeeds, the return value is the low-order doubleword of the file size, and, if lpFileSizeHigh is non-NULL, the function puts the high-order doubleword of the file size into the variable pointed to by that parameter.
If the function fails and lpFileSizeHigh is NULL, the return value is INVALID_FILE_SIZE. To get extended error information, call GetLastError.
If the function fails and lpFileSizeHigh is non-NULL, the return value is INVALID_FILE_SIZE and GetLastError will return a value other than NO_ERROR.
就不知这low-order doubleword和low-order word分别是什么意思?