ndo->ndo_snaplen = strtol(optarg, &end, 0);
if (optarg == end || *end != '\0'
|| ndo->ndo_snaplen < 0 || ndo->ndo_snaplen > MAXIMUM_SNAPLEN)
- error("invalid snaplen %s", optarg);
+ error("invalid snaplen %s (must be >= 0 and <= %d)",
+ optarg, MAXIMUM_SNAPLEN);
break;
case 'S':