--- a/netcat.c 	2010-08-07 23:22:36.504902769 -0400
+++ b/netcat.c	2010-08-07 23:33:22.934901172 -0400
@@ -805,61 +805,71 @@ atelnet(int nfd, unsigned char *buf, uns
 void
 build_ports(char *p)
 {
-	char *n, *endp;
+	char *n, *endp, *comma;
 	int hi, lo, cp;
 	int x = 0;
 
-	if ((n = strchr(p, '-')) != NULL) {
-		if (lflag)
-			errx(1, "Cannot use -l with multiple ports!");
-
-		*n = '\0';
-		n++;
-
-		/* Make sure the ports are in order: lowest->highest. */
-		hi = (int)strtoul(n, &endp, 10);
-		if (hi <= 0 || hi > PORT_MAX || *endp != '\0')
-			errx(1, "port range not valid");
-		lo = (int)strtoul(p, &endp, 10);
-		if (lo <= 0 || lo > PORT_MAX || *endp != '\0')
-			errx(1, "port range not valid");
-
-		if (lo > hi) {
-			cp = hi;
-			hi = lo;
-			lo = cp;
-		}
+	do {
+		comma = strchr(p, ',');
+		if (comma)
+			*comma = '\0';
+
+		if ((n = strchr(p, '-')) != NULL) {
+			if (lflag)
+				errx(1, "Cannot use -l with multiple ports!");
+
+			*n = '\0';
+			n++;
+
+			/* Make sure the ports are in order: lowest->highest. */
+			hi = (int)strtoul(n, &endp, 10);
+			if (hi <= 0 || hi > PORT_MAX || *endp != '\0')
+				errx(1, "port range not valid");
+			lo = (int)strtoul(p, &endp, 10);
+			if (lo <= 0 || lo > PORT_MAX || *endp != '\0')
+				errx(1, "port range not valid");
+
+			if (lo > hi) {
+				cp = hi;
+				hi = lo;
+				lo = cp;
+			}
 
-		/* Load ports sequentially. */
-		for (cp = lo; cp <= hi; cp++) {
+			/* Load ports sequentially. */
+			for (cp = lo; cp <= hi; cp++) {
+				portlist[x] = calloc(1, PORT_MAX_LEN);
+				if (portlist[x] == NULL)
+					err(1, NULL);
+				snprintf(portlist[x], PORT_MAX_LEN, "%d", cp);
+				x++;
+			}
+		} else {
+			hi = (int)strtoul(p, &endp, 10);
+			if (hi <= 0 || hi > PORT_MAX || *endp != '\0')
+				errx(1, "port range not valid");
 			portlist[x] = calloc(1, PORT_MAX_LEN);
-			if (portlist[x] == NULL)
+			if (portlist[0] == NULL)
 				err(1, NULL);
-			snprintf(portlist[x], PORT_MAX_LEN, "%d", cp);
+			snprintf(portlist[x], PORT_MAX_LEN, "%d", hi);
 			x++;
 		}
-
-		/* Randomly swap ports. */
-		if (rflag) {
-			int y;
-			char *c;
-
-			for (x = 0; x <= (hi - lo); x++) {
-				/* use random instead of arc4random */
-				y = (random() & 0xFFFF) % (hi - lo);
-				c = portlist[x];
-				portlist[x] = portlist[y];
-				portlist[y] = c;
-			}
+		if (comma)
+			p = comma + 1;
+	} while (comma);
+
+	/* Randomly swap ports. */
+	if (rflag) {
+		int max = x;
+		int y;
+		char *c;
+
+		for (x = 0; x < max; x++) {
+			/* use random instead of arc4random */
+			y = (random() & 0xFFFF) % max;
+			c = portlist[x];
+			portlist[x] = portlist[y];
+			portlist[y] = c;
 		}
-	} else {
-		hi = (int)strtoul(p, &endp, 10);
-		if (hi <= 0 || hi > PORT_MAX || *endp != '\0')
-			errx(1, "port range not valid");
-		portlist[0] = calloc(1, PORT_MAX_LEN);
-		if (portlist[0] == NULL)
-			err(1, NULL);
-		portlist[0] = p;
 	}
 }
 
--- nc/nc.1	2010-10-08 15:33:47.092169419 +0200
+++ nc/nc.1.comma	2010-10-08 15:38:10.701171878 +0200
@@ -235,7 +235,7 @@
 (in which case the local host is used).
 .Pp
 .Ar port Ns Op Ar s
-can be single integers or ranges.
+can be one or more comma-separated integers or ranges.
 Ranges are in the form nn-mm.
 In general,
 a destination port must be specified,