Module Iobuf.Poke

module Poke: Accessors 
    with type ('a, 'd, 'w) t = (read_write, 'w) t -> pos:int -> 'a -> unit 
    with type 'a bin_prot := 'a Bin_prot.Type_class.writer

Poke.bin_prot X.bin_write_t t x writes x to the beginning of t in binary form without advancing. You can use X.bin_size_t to tell how long it was. X.bin_write_t is only allowed to write that portion of the buffer to which you have access.