DOT11EXT_SEND_PACKET callback function

Important  The Native 802.11 Wireless LAN interface is deprecated in Windows 10 and later. Please use the WLAN Device Driver Interface (WDI) instead. For more information about WDI, see WLAN Universal Windows driver model.
The IHV Extensions DLL calls the Dot11ExtSendPacket function to transmit a packet through the wireless LAN (WLAN) adapter.


DOT11EXT_SEND_PACKET Dot11extSendPacket;

DWORD Dot11extSendPacket(
  HANDLE hDot11SvcHandle,
  ULONG uPacketLen,
  LPVOID pvPacket,
  HANDLE hSendCompletion



The handle used by the operating system to reference the WLAN adapter. This handle value was specified through a previous call to the Dot11ExtIhvInitAdapter IHV Handler function.


The length, in bytes, of the caller-allocated buffer referenced by the pvPacket parameter.


A pointer to a caller-allocated buffer that contains the data to be transmitted, as described in the Remarks section.


A handle value that uniquely identifies the send packet.

When the WLAN adapter completes the send operation, the operating system notifies the IHV Extensions DLL through a call to the Dot11ExtIhvSendPacketCompletion IHV Handler function. When making this call, the operating system passes the handle value of the packet through the hSendCompletion parameter.

Return Value

If the call succeeds, the function returns ERROR_SUCCESS. Otherwise, it returns an error code defined in Winerror.h.


The IHV Extensions DLL must follow these guidelines when calling the Dot11ExtSendPacket function.

  • The packet sent through a call of the Dot11ExtSendPacket function will complete asynchronously. The IHV Extensions DLL must not free the memory referenced by the pvPacket parameter until the Dot11ExtIhvSendPacketCompletion IHV Handler function is called with the same handle value as the hSendCompletion parameter.
  • The IHV Extensions DLL must set the hSendCompletion parameter to a value that uniquely identifies the packet data that is referenced by the pvPacket parameter.
For more information about the IHV Handler functions, see Native 802.11 IHV Handler Functions.

The buffer pointed to by pvPacket should contain the following packet data, specified in network byte order:

  • MAC address of destination (6 bytes), formatted according to the guidelines discussed in 802.11 MAC Header Management
  • IEEE EtherType (2 bytes)
  • Payload
This packet data is passed to the miniport driver.


Minimum supported client Available in Windows Vista and later versions of the Windows operating systems.
Target Platform Desktop
Header wlanihv.h (include Wlanihv.h)

See Also

Native 802.11 IHV Handler Functions



802.11 MAC Header Management