prefix.lua

local ffi = require("ffi")

local levee = require("levee")


ffi.cdef([[
	typedef struct { int len; } myproto_prefix_t;
]])


local SIZEOF_PREFIX = ffi.sizeof("myproto_prefix_t")


local h = levee.Hub()

local r, w = h.io:pipe()

local function writer()
	local prefix = ffi.new("myproto_prefix_t")
	prefix.len = 3
	w:write(ffi.cast("char *", prefix), SIZEOF_PREFIX)
	w:write("foo")
end

writer()

-- reader
local stream = r:stream()

stream:readin(SIZEOF_PREFIX)
local prefix = ffi.cast("myproto_prefix_t *", stream:value())

stream:readin(prefix.len)
-- local s = ffi.string(stream:value() + SIZEOF_PREFIX, prefix.len) vs -->
local s = ffi.string(stream:value(SIZEOF_PREFIX, prefix.len))
stream:trim(SIZEOF_PREFIX + prefix.len)

print(s)
assert(#stream == 0)