INATEventManager::put_NumberOfEntriesCallback method (natupnp.h)

The put_NumberOfEntriesCallback method enables the NAT application with UPnP technology to register a callback interface with the NAT. The system calls the first method in this callback interface if the number of NAT port mappings changes.

Syntax

HRESULT put_NumberOfEntriesCallback(
  [in] IUnknown *pUnk
);

Parameters

[in] pUnk

Pointer to an object that supports either the IUnknown interface or the IDispatch interface. See the Remarks section for more information.

Return value

If the method succeeds the return value is S_OK.

If the method fails, the return value is one of the following error codes.

Return code Description
E_ABORT
The operation was aborted.
E_FAIL
An unspecified error occurred.
E_INVALIDARG
One of the parameters is invalid.
E_NOINTERFACE
A specified interface is not supported.
E_NOTIMPL
A specified method is not implemented.
E_OUTOFMEMORY
The method was unable to allocate required memory.
E_POINTER
A pointer passed as a parameter is not valid.
E_UNEXPECTED
The method failed for unknown reasons.

Remarks

The object referred to by pUnk must either support the INATNumberOfEntriesCallback interface or the IDispatch interface. The NAT first queries pUnk for the INATNumberOfEntriesCallback interface. If this interface is not supported, the NAT queries pUnk for the IDispatch interface. If the IDispatch interface is not supported, the NumberOfEntriesCallback method returns E_FAIL.

If only IDispatch is supported, the NAT invokes the callback by calling IDispatch::Invoke with the dispatch ID specified as zero, which indicates the default method. This IDispatch method is passed the same parameters as the INATNumberOfEntriesCallback method, except that the first parameter passed is a string that indicates the reason the callback is invoked.

Requirements

Requirement Value
Minimum supported client Windows XP [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Target Platform Windows
Header natupnp.h
DLL Hnetcfg.dll

See also

IDispatch

INATEventManager

INATNumberOfEntriesCallback

Network Address Translation Traversal Interfaces

Network Address Translation Traversal Reference