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 		<UL>
 			<LI>Read callback - This function will be called when the decoder needs more input data.  The address of the buffer to be filled is supplied, along with the number of bytes the buffer can hold.  The callback may choose to supply less data and modify the byte count but must be careful not to overflow the buffer.  The callback then returns a status code chosen from FLAC__StreamDecoderReadStatus.</LI>
 			<LI>Write callback - This function will be called when the decoder has decoded a single frame of data.  The decoder will pass the frame metadata as well as an array of pointers (one for each channel) pointing to the decoded audio.</LI>
-			<LI>Metadata callback - This function will be called when the decoder has decoded a metadata block.  There will always be one STREAMINFO block per stream, followed by zero or more other metadata blocks.  These will be supplied by the decoder in the same order as they appear in the stream and always before the first audio frame.</LI>
+			<LI>Metadata callback - This function will be called when the decoder has decoded a metadata block.  There will always be one STREAMINFO block per stream, followed by zero or more other metadata blocks.  These will be supplied by the decoder in the same order as they appear in the stream and always before the first audio frame.  The metadata block that is passed in must not be modified, and it doesn't live beyond the callback, so you should make a copy of it with <TT>FLAC__metadata_object_copy()</TT> if you will need it elsewhere.</LI>
 			<LI>Error callback - This function will be called whenever an error occurs during decoding.</LI>
 		</UL>
 	</P>