OPTION_MPTCP_MPJ_SYN
mp_opt->suboptions |= OPTION_MPTCP_MPJ_SYN;
if (OPTION_MPTCP_MPJ_SYN & opts->suboptions) {
opts->suboptions = OPTION_MPTCP_MPJ_SYN;
#define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \
opt_mp_join = !!(mp_opt.suboptions & OPTION_MPTCP_MPJ_SYN);