cb.handler(ch);
Channel sc = sb.bind().sync().channel();
Channel cc = cb.connect().sync().channel();
FileRegion region = new DefaultFileRegion(
new FileInputStream(file).getChannel(), startOffset, data.length - bufferSize);
FileRegion emptyRegion = new DefaultFileRegion(new FileInputStream(file).getChannel(), 0, 0);
// Do write ByteBuf and then FileRegion to ensure that mixed writes work
// Also, write an empty FileRegion to test if writing an empty FileRegion does not cause any issues.
//
// See https://github.com/netty/netty/issues/2769