devia大牛来看下．使用FileObject写文件的问题．

我在IRP_MJ_SETINFORMATION中，先把Irp下发执行完毕．
然后自己build一个MJ_WRITE的IRP向原文件尾部写4个字节．
在IoCallDriver(DeviceObject, Irp);时蓝．．．何解呢？

IRP_MJ_SETINFORMATION中不能使用FileObject写数据？

1。如果你要在文件尾进行追加的话就无须特意移动文件读写指针了，解释如下：

If the following condition is true, this indicates that the current end of file should be used instead of an explicit file offset value:
IrpSp->Parameters.Write.ByteOffset.LowPart == FILE_WRITE_TO_END_OF_FILE and IrpSp->Parameters.Write.ByteOffset.HighPart == -1

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.Write.ByteOffset == NULL

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

2。如何自己发IRP来完成IO，你在论坛找找我以前发的OSR上的Demo
http://bbs.driverdevelop.com/htm_data/39/0704/101220.html

历害，果然是好大牛．顶个～