hold_dm
dp->d_dmp = hold_dm(str, qflag, sqtype);
fp->f_dmp = hold_dm(str, qflag, sqtype);
dp->d_dmp = hold_dm(str, qflag, sqtype);
dp->d_dmp = hold_dm(str, qflag, sqtype);
extern perdm_t *hold_dm(struct streamtab *, uint32_t, uint32_t);