# CoMarshalInterThreadInterfaceInStream

Marshals an interface pointer from one thread to another thread in the same process.

HRESULT CoMarshalInterThreadInterfaceInStream(

REFIID riid, | //Reference to the identifier of the interface
LPUNKNOWN pUnk, | //Pointer to the interface to be marshaled
LPSTREAM * ppStm | //Indirect pointer
); |

Parameters

riid
  [in] Reference to the identifier of the interface to be marshaled.
pUnk
  [in] Pointer to the interface to be marshaled, which must be derived from IUnknown; can be NULL.
ppStm
  [out] Indirect pointer to the stream that contains the marshaled interface.

Return Values

This function supports the standard return value E_OUTOFMEMORY, as well as the following:

S_OK
  The interface was marshaled successfully.

Remarks

The CoMarshalInterThreadInterfaceInStream function enables an object to easily and reliably marshal an interface pointer to another thread in the same process. The stream returned in ppStm is guaranteed to behave correctly when a client running in the receiving thread attempts to unmarshal the pointer. The client can then call the CoGetInterfaceAndReleaseStream to unmarshal the interface pointer and release the stream object.

The CoMarshalInterThreadInterfaceInStream function performs the following tasks:

1. Creates a stream object.

2. Passes the stream object’s IStream pointer to CoMarshalInterface.

3. Returns the IStream pointer to the caller.

See Also

CoGetInterfaceAndReleaseStream