XTYP_WILDCONNECT transaction
Enables a client to establish a conversation on each of the server's service name and topic name pairs that match the specified service name and topic name. A Dynamic Data Exchange (DDE) server callback function, DdeCallback, receives this transaction when a client specifies a NULL service name, a NULL topic name, or both in a call to the DdeConnect or DdeConnectList function.
#define XCLASS_DATA 0x2000
#define XTYPF_NOBLOCK 0x0002
#define XTYP_WILDCONNECT (0x00E0 | XCLASS_DATA | XTYPF_NOBLOCK)
Parameters
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uType
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The transaction type.
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uFmt
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Not used.
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hconv
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Not used.
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hsz1
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A handle to the topic name. If this parameter is NULL, the client is requesting a conversation on all topic names that the server supports.
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hsz2
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A handle to the service name. If this parameter is NULL, the client is requesting a conversation on all service names that the server supports.
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hdata
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Not used.
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dwData1
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A pointer to a CONVCONTEXT structure that contains context information for the conversation. If the client is not a DDEML application, this parameter is set to 0.
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dwData2
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Specifies whether the client is the same application instance as the server. If the parameter is 1, the client is same instance. If the parameter is 0, the client is a different instance.
Return value
The server should return a data handle that identifies an array of HSZPAIR structures. The array should contain one structure for each service-name and topic-name pair that matches the service-name and topic-name pair requested by the client. The array must be terminated by a NULL string handle. The system sends the XTYP_CONNECT_CONFIRM transaction to the server to confirm each conversation and to pass the conversation handles to the server. The server will not receive these confirmations if it specified the CBF_SKIP_CONNECT_CONFIRMS flag in the DdeInitialize function.
The server should return NULL to refuse the XTYP_WILDCONNECT transaction.
Remarks
This transaction is filtered if the server application specified the CBF_FAIL_CONNECTIONS flag in the DdeInitialize function.
A server cannot block this transaction type; the CBR_BLOCK return code is ignored.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client |
Windows 2000 Professional [desktop apps only] |
| Minimum supported server |
Windows 2000 Server [desktop apps only] |
| Header |
|
See also
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Reference
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Conceptual