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CPullPin::DecideAllocator

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Microsoft DirectShow 9.0

CPullPin::DecideAllocator

The DecideAllocator method negotiates an allocator with the output pin.

Syntax

  virtual HRESULT DecideAllocator(
    IMemAllocator *pAlloc,
    ALLOCATOR_PROPERTIES *pProps
);

Parameters

pAlloc

Pointer to the IMemAllocator interface of the input pin's preferred allocator, or NULL.

pProps

Pointer to an optional ALLOCATOR_PROPERTIES structure that contains the input pin's buffer requirements. 

Return Values

Returns S_OK if successful, or an error code otherwise.

Remarks

This method calls the IAsyncReader::RequestAllocator method to negotiate an allocator. It passes the pAlloc parameter directly to the RequestAllocator method. It passes the pProps parameter to RequestAllocator if pProps is non-NULL; otherwise, it creates an ALLOCATOR_PROPERTIES structure with a default request of three 64K buffers.

Requirements

**  Header:** Include Pullpin.h and Streams.h.

**  Library:** Use Strmbase.lib (retail builds) or Strmbasd.lib (debug builds).

See Also