Returns a suggested maximum buffer size for the next call to read.
template< class DynamicBuffer> std::size_t read_size_hint( DynamicBuffer& buffer) const;
This function returns a reasonable upper limit on the number of bytes for the size of the buffer passed in the next call to read. The number is determined by the state of the current frame and whether or not the permessage-deflate extension is enabled.
The buffer which will be used for reading. The implementation
will query the buffer to obtain the optimum size of a subsequent