Gets or sets the high - order word of the file position at which to start the transfer 获取或设置启动传输的文件位置的高序位字。
2.
High - order word 高序位文字
3.
Pointer to the variable where the high - order word of the file size is returned . this parameter can be null if the application does not require the high - order word 就是说有的应用程序要求文件大小的高字节的返回值。一般不用这个，直接用null代替即可。
4.
[ out ] pointer to the variable where the high - order word of the file size is returned . this parameter can be null if the application does not require the high - order word 就是说有的应用程序要求文件大小的高字节的返回值。一般不用这个，直接用null代替即可。
