Profiling library
Library core_profiler
val get_header_chunk : unit -> (, _ ) Iobuf.t
val ensure_free : int -> unit

All of these will push the current chunk into the list of previous chunks first; a new chunk will then be allocated on the next write.

val is_empty : unit -> bool

Is the main (short message) buffer empty?

val get_chunks : unit -> ( Core.read_write, Iobuf.no_seek ) Iobuf.t list
module Unsafe_internals : sig ... end

To aid producing test cases for Reader.