Type Definition flac_sys::FLAC__StreamDecoderTellCallback

type FLAC__StreamDecoderTellCallback = Option<unsafe extern "C" fn(decoder: *const FLAC__StreamDecoder, absolute_byte_offset: *mut FLAC__uint64, client_data: *mut c_void) -> FLAC__StreamDecoderTellStatus>;

Signature for the tell callback.

A function pointer matching this signature may be passed to FLAC__stream_decoder_init*_stream(). The supplied function will be called when the decoder wants to know the current position of the stream. The callback should return the byte offset from the beginning of the stream.

Here is an example of a tell callback for stdio streams: \code FLAC__StreamDecoderTellStatus tell_cb(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data) { FILE file = ((MyClientData)client_data)->file; off_t pos; if(file == stdin) return FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED; else if((pos = ftello(file)) < 0) return FLAC__STREAM_DECODER_TELL_STATUS_ERROR; else { *absolute_byte_offset = (FLAC__uint64)pos; return FLAC__STREAM_DECODER_TELL_STATUS_OK; } } \endcode

\note In general, FLAC__StreamDecoder functions which change the state should not be called on the \a decoder while in the callback.

\param decoder The decoder instance calling the callback. \param absolute_byte_offset A pointer to storage for the current offset from the beginning of the stream. \param client_data The callee's client data set through FLAC__stream_decoder_init_*(). \retval FLAC__StreamDecoderTellStatus The callee's return status.