Data::Buffer implements a low-level binary buffer in which
you can get and put integers, strings, and other data.
Internally the implementation is based on pack and unpack,
such that Data::Buffer is really a layer on top of those
built-in functions.

All of the get_* and put_* methods respect the internal
offset state in the buffer object. This means that you
should read data out of the buffer in the same order that
you put it in.