NdisUnChainBufferAtFront的疑问

我用NdisChainBufferAtFront（pPacket,pMdl)完毕后想用NdisUnChainBufferAtFront(pPacket,NULL)然后连接新的buffer,为什么执行到NdisUnChainBuffer时SoftIce就提示出错呢。（pMdl为PMDL对象）。  :mad:

搞定了，NdisUnchainBufferAtFront第二个参数不能为NULL,必须为PNDIS_BUFFER对象。

NdisUnchainBufferAtFront
VOID
  NdisUnchainBufferAtFront(
    IN OUT PNDIS_PACKET  Packet,
    OUT PNDIS_BUFFER  *Buffer
    );
NdisUnchainBufferAtFront removes the buffer descriptor at the head of the chain of buffer descriptors for a given packet.

Parameters
Packet
Points to the packet descriptor.
Buffer
Points to a caller-supplied variable in which this function returns a pointer to the removed buffer descriptor. If no buffer is chained to the given packet, this variable is set to NULL.
Comments
NdisUnchainBufferAtFront returns a pointer to the buffer descriptor it removed from the buffer descriptor chain of the given packet.

It also resets the valid counts for the packet to FALSE, thereby forcing NdisQueryPacket to recalculate information about the given packet if it is called subsequently with that packet.

Callers of NdisUnchainBufferAtFront can run at any IRQL.

See Also
NdisChainBufferAtFront, NdisQueryPacket, NdisUnchainBufferAtBack