Re: Bug with new interface dependencies on custom IStream with SDK

David,

As it turns out, this problem has been reported before. The resolution was
that the IStream implementation was returning E_NOINTERFACE but was also
returning a junk pointer for the interface from the QueryInterface call, and
then wmvcore would call Release() on it; hijinks ensued. So you might want
to sanity-check and make sure that the value you're returning in *ppv is in
fact NULL.

That, at least, is my best guess.

Becky

This posting is provided AS IS with no warranties and confers no rights.

"David Huseby" wrote:

> Both v8 and v9 encoded content causes the NULL exceptions. This problem is
> new in the 9.5 SDK.
>
> Hrm, it isn't DRM related huh? The IWMSyncReader2 object calls
> IStream::QueryInterface four times looking for pointers to the following
> interfaces:
>
> IID_Istream
> IID_ISequentialStream
> IID_IWMIStreamProps
> 94BC0598-C3D2-11D3-BEDF-00C04F612986
>
> If it isn't DRM related then please post all of the API details for the
> interface identified by REFIID: 94BC0598-C3D2-11D3-BEDF-00C04F612986. This
> is an undocumented interface and IWMSyncReader2 depends on. If it isn't DRM
> related then you will be able to post the interface details to this list or
> at least post a link to the documentation on MSDN.
>
> When I set the interface pointer to NULL and return E_NOTIMPL, the
> IWMSyncReader2 object promptly dereferences it and causes an exception. I
> need to be able to implement that interface but without documentation it is
> impossible.
>
> Thanks,
> Dave
>
>
.

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