请问IrpSp->Parameters.Read.ByteOffset.QuadPart 的含义

  1.什么时候 IrpSp->Parameters.Read.ByteOffset.QuadPart ==0?
2 IrpSp->Parameters.Read.ByteOffset.QuadPart ==0 时是不是就是意味着到了文件头?
谢谢@!

Pointer to a LARGE_INTEGER variable that specifies the starting byte offset within the file of the data to be read.
Under certain circumstances, this parameter might validly contain a NULL or negative value. For example, if the file object was opened for synchronous I/O, and one of the following conditions is true, this indicates that the current file position should be used instead of an explicit file offset value:

IrpSp->Parameters.Read.ByteOffset == NULL

IrpSp->Parameters.Read.ByteOffset.LowPart == FILE_USE_FILE_POINTER_POSITION and IrpSp->Parameters.Read.ByteOffset.HighPart == -1.

谢谢,问题解决了,原来不是IrpSp->Parameters.Read.ByteOffset.LowPart 的问题,是改名时没有处理好,在SfWrite中再判断一下是否需要加密就解决好了