XRS_ID
if (uap->uc_mcontext.xrs.xrs_id == XRS_ID)
return (uc->uc_mcontext.xrs.xrs_id == XRS_ID);
if (uc->uc_mcontext.xrs.xrs_id == XRS_ID)
uc->uc_mcontext.xrs.xrs_id = XRS_ID;
return (uc->uc_mcontext.xrs.xrs_id == XRS_ID);
if (uc->uc_mcontext.xrs.xrs_id == XRS_ID)
uc->uc_mcontext.xrs.xrs_id = XRS_ID;