STRDERRNONPERSIST
{ SF(STRDERRNONPERSIST), "nonpersistent read errors" },
stp->sd_flag &= ~STRDERRNONPERSIST;
stp->sd_flag |= STRDERRNONPERSIST;
stp->sd_flag &= ~STRDERRNONPERSIST;
stp->sd_flag |= STRDERRNONPERSIST;
erropt |= (stp->sd_flag & STRDERRNONPERSIST) ? RERRNONPERSIST :
if ((stp->sd_flag & STRDERRNONPERSIST) && !ispeek) {
stp->sd_flag &= ~STRDERRNONPERSIST;
stp->sd_flag |= STRDERRNONPERSIST;