Minor follow-ups to #508.

Change the internal command-line option code for --dscp from the literal
'5' to a constant defined as OPT_DSCP.

Add manpage text for --dscp option.

Tweak help text for --dscp (while here, fix problem in --tos text).

src/iperf3.1

@@ -171,7 +171,10 @@ only use IPv4
 only use IPv6
 .TP
 .BR -S ", " --tos " \fIn\fR"
-set the IP 'type of service'
+set the IP type of service
+.TP
+.BR "--dscp " \fIdscp\fR
+set the IP DSCP bits.  Both numeric and symbolic values are accepted.
 .TP
 .BR -L ", " --flowlabel " \fIn\fR"
 set the IPv6 flow label (currently only supported on Linux)

src/iperf_api.c

@@ -645,7 +645,7 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
         {"version4", no_argument, NULL, '4'},
         {"version6", no_argument, NULL, '6'},
         {"tos", required_argument, NULL, 'S'},
-        {"dscp", required_argument, NULL, '5'},
+        {"dscp", required_argument, NULL, OPT_DSCP},
 #if defined(HAVE_FLOWLABEL)
         {"flowlabel", required_argument, NULL, 'L'},
 #endif /* HAVE_FLOWLABEL */
@@ -852,7 +852,7 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
 		}
 		client_flag = 1;
                 break;
-	    case '5':
+	    case OPT_DSCP:
                 test->settings->tos = parse_qos(optarg);
 		if(test->settings->tos < 0) {
 			i_errno = IEBADTOS;

src/iperf_api.h

@@ -53,6 +53,7 @@ struct iperf_stream;
 #define OPT_FORCEFLUSH 7
 #define OPT_NO_FQ_SOCKET_PACING 9 /* UNUSED */
 #define OPT_FQ_RATE 10
+#define OPT_DSCP 11
 
 /* states */
 #define TEST_START 1

src/iperf_locale.c

@@ -1,5 +1,5 @@
 /*--------------------------------------------------------------- 
- * iperf, Copyright (c) 2014, 2016, The Regents of the University of
+ * iperf, Copyright (c) 2014, 2016, 2017, The Regents of the University of
  * California, through Lawrence Berkeley National Laboratory (subject
  * to receipt of any required approvals from the U.S. Dept. of
  * Energy).  All rights reserved.
@@ -148,8 +148,8 @@ const char usage_longstr[] = "Usage: iperf3 [-s|-c host] [options]\n"
                            "  -N, --no-delay            set TCP/SCTP no delay, disabling Nagle's Algorithm\n"
                            "  -4, --version4            only use IPv4\n"
                            "  -6, --version6            only use IPv6\n"
-                           "  -S, --tos N               set the IP 'type of service 0-255'\n"
-                           "    , --dscp N or dscp val  set the IP 'dscp value either 0-63 or symbolic'\n"
+                           "  -S, --tos N               set the IP type of service, 0-255\n"
+                           "  --dscp N or --dscp val    set the IP dscp value, either 0-63 or symbolic\n"
 #if defined(HAVE_FLOWLABEL)
                            "  -L, --flowlabel N         set the IPv6 flow label (only supported on Linux)\n"
 #endif /* HAVE_FLOWLABEL */