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IAsyncReader::Length

 
Microsoft DirectShow 9.0

IAsyncReader::Length

The Length method retrieves the total length of the stream.

Syntax

  HRESULT Length(
  LONGLONG *pTotal,
  LONGLONG *pAvailable
);

Parameters

pTotal

Pointer to a variable that receives the length of the stream, in bytes.

pAvailable

Pointer to a variable that receives the portion of the stream that is currently available, in bytes.

Return Values

Returns an HRESULT value. Possible values include the following.

Return code Description
S_OK Success.
VFW_S_ESTIMATED The returned values are estimates; for example, if the file is being read over a network.
E_UNEXPECTED The file is not open or no longer exists.

Remarks

For streams retrieved over a network, the entire stream may not be available at first. Read operations beyond the available length might block for a long period of time, until that portion of the stream becomes available.

Requirements

Header: Declared in Strmif.h; include Dshow.h.

Library: Use Strmiids.lib.

See Also