| Microsoft DirectX 9.0 SDK Update (Summer 2003) |
DPN_MSGID_ENUM_HOSTS_QUERY Message
Microsoft® DirectPlay® sends the DPN_MSGID_ENUM_HOSTS_QUERY message to the host's message handler when a peer or client is enumerating the available hosts.
The DPNMSG_ENUM_HOSTS_QUERY structure contains information for the DPN_MSGID_ENUM_HOSTS_QUERY system message.
Syntax
typedef struct _DPNMSG_ENUM_HOSTS_QUERY {
DWORD dwSize;
IDirectPlay8Address *pAddressSender;
IDirectPlay8Address *pAddressDevice;
PVOID pvReceivedData;
DWORD dwReceivedDataSize;
DWORD dwMaxResponseDataSize;
PVOID pvResponseData;
DWORD dwResponseDataSize;
PVOID pvResponseContext;
} DPNMSG_ENUM_HOSTS_QUERY, *PDPNMSG_ENUM_HOSTS_QUERY;Members
- dwSize
- Size of this structure.
- pAddressSender
- Pointer an IDirectPlay8Address interface specifying the address of the sender. You must call IDirectPlay8Address::AddRef to increment the interface's reference count. Call IDirectPlay8Address::Release when you no longer need the interface.
- pAddressDevice
- Pointer an IDirectPlay8Address interface specifying the address of the device. You must call IDirectPlay8Address::AddRef to increment the interface's reference count. Call IDirectPlay8Address::Release when you no longer need the interface.
- pvReceivedData
- Pointer to the data received from the enumeration.
- dwReceivedDataSize
- Size of the data pointed to in the pvReceivedData member.
- dwMaxResponseDataSize
- Maximum allowed size for the enumeration response.
- pvResponseData
- Pointer to the response data from the enumeration. This data must be valid beyond the scope of the callback message handler. It cannot be stack-based. You will receive a DPN_MSGID_RETURN_BUFFER message when DirectPlay is finished with this buffer.
- dwResponseDataSize
- Size of the data pointed to in the pvResponseData member.
- pvResponseContext
- Pointer to a response context value. This value will be passed to the host's message handler with the DPN_MSGID_RETURN_BUFFER message as the pvUserContext member of the associated structure.
Remarks
Return from the message callback function with DPN_OK.
When you respond normally to this query, DirectPlay will send you a DPN_MSGID_RETURN_BUFFER message once the buffer is no longer needed. You can then safely free the buffer.
You can reject the query by returning a value that is not equal to DPN_OK. However, when you reject a query, DirectPlay does not send a reply, does not need a reply buffer, and does not generate a DPN_MSGID_RETURN_BUFFER message.
Message Information
Header dplay8.h Minimum operating systems Windows 98, Pocket PC 2002