`type in_addr``= Unsigned.uint32`

`val in_addr_t : Unsigned.uint32 S.typ`
`val in_addr : in_addr Ctypes.structure S.typ`
`val s_addr : (in_addr, in_addr Ctypes.structure) S.field`

`type t`

`val t : t Ctypes.structure S.typ`
`val sin_family : (sa_family_t, t Ctypes.structure) S.field`
`val sin_port : (in_port, t Ctypes.structure) S.field`
`val sin_addr : (in_addr Ctypes.structure, t Ctypes.structure) S.field`