test: check I can read; write as well as write; read
test: check I can read; write as well as write; read

Signed-off-by: David Scott <63c9eb0ea83039690fefa11afe17873ba8278a56@citrix.com>

samoht/ocaml-vchan,mirage/ocaml-vchan,mirage/ocaml-vchan,djs55/ocaml-vchan,djs55/ocaml-vchan,djs55/ocaml-vchan,samoht/ocaml-vchan,mirage/ocaml-vchan,samoht/ocaml-vchan