mq_des
mqhp->mq_des = (uintptr_t)mqdp;
uint64_t mq_des; /* pointer to msg Q descriptor */
mqhp->mq_des = 0;
if (mqhp->mq_des == (uintptr_t)mqdp &&
mqhp->mq_des = 0;
struct mq_des *mqd_next; /* list of all open mq descriptors, */
struct mq_des *mqd_prev; /* needed for fork-safety */
if (mqhp->mq_des == (uintptr_t)mqdp &&
mqhp->mq_des = 0;