NetPacketGetExtension function


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NetAdapterCx is preview only in Windows 10, version 1903.

The NetPacketGetExtension method retrieves information stored in one of a packet's extensions.


void * NetPacketGetExtension(
  const NET_PACKET *packet,
  SIZE_T           offset



A pointer to a NET_PACKET structure.


The offset, in bytes, to the desired NET_PACKET_EXTENSION from the beginning of the packet's descriptor.

Return Value

Returns a pointer to a structure at the given extension offset that represents packet extension information.


NIC client drivers typically query offsets for packet extensions during datapath queue creation, then store them in their queue context space so they don't have to query them too often. For an example of this, see Transmit and receive queues. These offsets are then passed to NetPacketGetExtension to retrieve data for each packet extension.


Target Platform Universal
Minimum KMDF version 1.29
Header packet.h (include netadaptercx.h)
IRQL Any level as long as target memory is resident

See Also

Packet descriptors and extensions

Transmit and receive queues