# bend-sendfile: package entry for BendHub.
# Source: bendlang/bend PR #1117 (reviewed by VictorTaelin; closed as
# WONTFIX (CAPACITY) and rerouted here: "a foreign effect a hub package can
# ship with no loss ... the same C code").
#
# The file's bytes, from an offset, straight onto a socket: the kernel's
# sendfile on the C lane, so no byte passes through the program; the JS twin
# copies through a buffer (Node has no sendfile) and says so. Every lane
# leaves the file's position alone. Done once all len bytes are out; a file
# that ends first fails with ENODATA after what it had went out.
import Base

# The file's bytes from off, len of them, onto the socket: the kernel's
# sendfile on the C lane, so no byte passes through the program; every
# lane leaves the file's position alone. Done once all len are out; a
# file that ends first fails with ENODATA after what it had went out.
def File.sendfile(sock: Socket, file: File, off: U32, len: U32) ->
  IO(Socket & File & Result<&1, &1, U32 & String, Unit>):
  import "./file_sendfile.c"
  import "./file_sendfile.js"