sysctl_str
if (sysctl_str(buf, NULL, dp->eq_preamp, sizeof(dp->eq_preamp)))
return (sysctl_str(buf, arg, dp->eq_preamp, sizeof(dp->eq_preamp)));
return (sysctl_str(buf, arg, dp->play.format, sizeof(dp->play.format)));
return (sysctl_str(buf, arg, dp->rec.format, sizeof(dp->rec.format)));