The AVIStreamLength function returns the length of the stream.
STDAPI_(LONG) AVIStreamLength(
PAVISTREAM pavi
);
Returns the stream's length, in samples, if successful or -1 otherwise.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in vfw.h.
Import Library: Use vfw32.lib.
AVIFile Functions and Macros Overview, AVIFile Functions