Index: sbin/ifconfig/ifconfig.c
===================================================================
--- sbin/ifconfig/ifconfig.c
+++ sbin/ifconfig/ifconfig.c
@@ -1410,7 +1410,28 @@
 			}
 		} else
 			warn("unable to allocate memory for interface"
-			    "description");
+			    " description");
+		break;
+	}
+	for (;;) {
+		if ((descr = reallocf(descr, descrlen)) != NULL) {
+			ifr.ifr_buffer.buffer = descr;
+			ifr.ifr_buffer.length = descrlen;
+			if (ioctl(s, SIOCGIFDNAME, &ifr) == 0) {
+				if (ifr.ifr_buffer.buffer == descr) {
+					if (strlen(descr) > 0 && strncmp(name,
+					    descr, descrlen) != 0) {
+						printf("\tinitname: %s\n",
+						    descr);
+					}
+				} else if (ifr.ifr_buffer.length > descrlen) {
+					descrlen = ifr.ifr_buffer.length;
+					continue;
+				}
+			}
+		} else
+			warn("unable to allocate memory for interface"
+			    " initname");
 		break;
 	}
 
Index: sys/net/if.c
===================================================================
--- sys/net/if.c
+++ sys/net/if.c
@@ -2708,6 +2708,28 @@
 		ifp->if_flags &= ~IFF_RENAMING;
 		break;
 
+	case SIOCGIFDNAME:
+		error = 0;
+		if (ifp->if_dname == NULL || ifp->if_dunit == IF_DUNIT_NONE) {
+			error = ENOMSG;
+		} else {
+			descrlen = snprintf(new_name, sizeof(new_name), "%s%u",
+			    ifp->if_dname, ifp->if_dunit);
+			if (descrlen < 0) {
+				error = ENOMSG;
+				break;
+			}
+			/* space for terminating nul */
+			descrlen++;
+			if (ifr_buffer_get_length(ifr) < descrlen)
+				ifr_buffer_set_buffer_null(ifr);
+			else
+				error = copyout(new_name,
+				    ifr_buffer_get_buffer(ifr), descrlen);
+			ifr_buffer_set_length(ifr, descrlen);
+		}
+		break;
+
 #ifdef VIMAGE
 	case SIOCSIFVNET:
 		error = priv_check(td, PRIV_NET_SETIFVNET);
Index: sys/sys/sockio.h
===================================================================
--- sys/sys/sockio.h
+++ sys/sys/sockio.h
@@ -147,4 +147,6 @@
 
 #define	SIOCGIFDOWNREASON	_IOWR('i', 154, struct ifdownreason)
 
+#define	SIOCGIFDNAME	_IOWR('i', 155, struct ifreq)	/* get ifnet dname + dunit */ 
+
 #endif /* !_SYS_SOCKIO_H_ */