Function libwebp_sys::WebPDemuxGetChunk

pub unsafe extern "C" fn WebPDemuxGetChunk(
    dmux: *const WebPDemuxer, 
    fourcc: *const c_char, 
    chunk_number: c_int, 
    iter: *mut WebPChunkIterator
) -> c_int

This is supported on feature="demux" only.