pub fn socketpair(
    domain: AddressFamily,
    type_: SocketType,
    flags: SocketFlags,
    protocol: Option<Protocol>,
) -> Result<(OwnedFd, OwnedFd)>pub fn socketpair(
    domain: AddressFamily,
    type_: SocketType,
    flags: SocketFlags,
    protocol: Option<Protocol>,
) -> Result<(OwnedFd, OwnedFd)>