IPCID_TO_IX
msqid = IPCID_TO_IX(msqidr);
ix = IPCID_TO_IX(msqid);
msqid = IPCID_TO_IX(msqidr);
ix = IPCID_TO_IX(semid);
semid = IPCID_TO_IX(usemid); /* Convert back to zero origin */
segnum = IPCID_TO_IX(shmid);
segnum = IPCID_TO_IX(shmmap_se->shmid);
shmseg = &shmsegs[IPCID_TO_IX(shmmap_se->shmid)];
shm_free_segment(IPCID_TO_IX(shmid));
shmsegs[IPCID_TO_IX(shmmap_se->shmid)].shm_nattch++;
shmsegs[IPCID_TO_IX(shmmap_se->shmid)].shm_nattch--;
shmseg = &shmsegs[IPCID_TO_IX(shmmap_se->shmid)];