diff --git a/CHANGES b/CHANGES
index d0d974d..e5d3261 100644
--- a/CHANGES
+++ b/CHANGES
@@ -47,6 +47,8 @@ Coding:
 
 	Renamed xioopts_t to xioparms_t to avoid confusion with xioopts module.
 
+	Moved multicast related code from xioopts.c to xio-ip.c and xio-ip6.c
+
 Porting:
 	Removed Config/ because its contents have not been maintained for many
 	years.
diff --git a/test.sh b/test.sh
index 24dde14..676b8dd 100755
--- a/test.sh
+++ b/test.sh
@@ -7991,6 +7991,14 @@ elif ! feat=$(testfeats ip4 udp) || ! runsip4 >/dev/null; then
     $PRINTF "test $F_n $TEST... ${YELLOW}$feat not available${NORMAL}\n" $N
     numCANT=$((numCANT+1))
     listCANT="$listCANT $N"
+elif ! a=$(testaddrs UDP4-RECV UDP4-SENDTO); then
+    $PRINTF "test $F_n $TEST... ${YELLOW}Address $a not available${NORMAL}\n" $N
+    numCANT=$((numCANT+1))
+    listCANT="$listCANT $N"
+elif ! o=$(testoptions ip-add-membership bind) >/dev/null; then
+    $PRINTF "test $F_n $TEST... ${YELLOW}Option $o not available${NORMAL}\n" $N
+    numCANT=$((numCANT+1))
+    listCANT="$listCANT $N"
 else
 tf="$td/test$N.stdout"
 te="$td/test$N.stderr"
@@ -8012,19 +8020,26 @@ kill "$pid1" 2>/dev/null; wait;
 if [ "$rc2" -ne 0 ]; then
    $PRINTF "$FAILED: $TRACE $SOCAT:\n"
    echo "$CMD1 &"
+   cat "${te}1" >&2
    echo "$CMD2"
-   cat "${te}1"
-   cat "${te}2"
+   cat "${te}2" >&2
    numFAIL=$((numFAIL+1))
     listFAIL="$listFAIL $N"
 elif ! echo "$da" |diff - "$tf" >"$tdiff"; then
    $PRINTF "$FAILED\n"
+   echo "$CMD1 &"
+   cat "${te}1" >&2
+   echo "$CMD2"
+   cat "${te}2" >&2
    cat "$tdiff"
    numFAIL=$((numFAIL+1))
     listFAIL="$listFAIL $N"
 else
    $PRINTF "$OK\n"
-   if [ -n "$debug" ]; then cat $te; fi
+    if [ "$VERBOSE" ]; then echo "$CMD0 &"; fi
+    if [ "$DEBUG" ];   then cat "${te}0" >&2; fi
+    if [ "$VERBOSE" ]; then echo "$CMD1"; fi
+    if [ "$DEBUG" ];   then cat "${te}1" >&2; fi
    numOK=$((numOK+1))
 fi
 fi ;; # NUMCOND, feats
@@ -12580,7 +12595,7 @@ N=$((N+1))
 # fixed in 1.7.3.2
 NAME=USE_IPV6_JOIN_GROUP
 case "$TESTS" in
-*%$N%*|*%functions%*|*%bugs%*|*%socket%*|*%ip6%*|*%udp%*|*%udp6%*|*%dgram%*|*%$NAME%*)
+*%$N%*|*%functions%*|*%bugs%*|*%socket%*|*%ip6%*|*%udp%*|*%udp6%*|*%dgram%*|*%multicast%*|*%$NAME%*)
 TEST="$NAME: is option ipv6-join-group used"
 # Invoke socat with option ipv6-join-group on UDP6 address.
 # Terminate immediately, do not transfer data.
diff --git a/xio-ip.c b/xio-ip.c
index fe2b608..0d595e9 100644
--- a/xio-ip.c
+++ b/xio-ip.c
@@ -131,7 +131,7 @@ unsigned long res_opts() {
  socktype: SOCK_STREAM, SOCK_DGRAM, ...
  protocol: IPPROTO_UDP, IPPROTO_TCP
  sau: an uninitialized storage for the resulting socket address
- returns: STAT_OK, STAT_RETRYLATER
+ returns: STAT_OK, STAT_RETRYLATER, STAT_NORETRY, prints message
 */
 int xiogetaddrinfo(const char *node, const char *service,
 		   int family, int socktype, int protocol,
@@ -662,6 +662,201 @@ int xiolog_ancillary_ip(struct cmsghdr *cmsg, int *num,
 #endif /* defined(HAVE_STRUCT_CMSGHDR) && defined(CMSG_DATA) */
 
 
+#if defined(HAVE_STRUCT_IP_MREQ) || defined (HAVE_STRUCT_IP_MREQN)
+int xiotype_ip_add_membership(
+	char *tokp,
+	const struct optname *ent,
+	struct opt *opt)
+{
+	/* we do not resolve the addresses here because we do not yet know
+	   if we are coping with a IPv4 or IPv6 socat address */
+	const char *ends[] = { ":", NULL };
+	const char *nests[] = { "[","]", NULL };
+	char buff[512], *buffp=buff; size_t bufspc = sizeof(buff)-1;
+	int parsres;
+
+	/* parse first IP address, expect ':' */
+	/*! result= */
+	parsres =
+		nestlex((const char **)&tokp, &buffp, &bufspc,
+			ends, NULL, NULL, nests,
+			true, false, false);
+	if (parsres < 0) {
+		Error1("option too long:  \"%s\"", tokp);
+		return -1;
+	} else if (parsres > 0) {
+		Error1("syntax error in \"%s\"", tokp);
+		return -1;
+	}
+	if (*tokp != ':') {
+		Error1("syntax in option %s: missing ':'", tokp);
+	}
+	*buffp++ = '\0';
+	if ((opt->value.u_string/*multiaddr*/ = strdup(buff)) == NULL) {
+	   Error1("strdup(\"%s\"): out of memory", buff);
+	   return -1;
+	}
+
+	++tokp;
+	/* parse second IP address, expect ':' or '\0'' */
+	buffp = buff;
+	/*! result= */
+	parsres =
+		nestlex((const char **)&tokp, &buffp, &bufspc,
+			ends, NULL, NULL, nests,
+			true, false, false);
+	if (parsres < 0) {
+		Error1("option too long:  \"%s\"", tokp);
+		return -1;
+	} else if (parsres > 0) {
+		Error1("syntax error in \"%s\"", tokp);
+		return -1;
+	}
+	*buffp++ = '\0';
+	if ((opt->value2.u_string/*param2*/ = strdup(buff)) == NULL) {
+	   Error1("strdup(\"%s\"): out of memory", buff);
+	   free(opt->value.u_string);
+	   return -1;
+	}
+
+
+#if HAVE_STRUCT_IP_MREQN
+	if (*tokp++ == ':') {
+		strncpy(opt->value3.u_string/*ifindex*/, tokp, IF_NAMESIZE);	/* ok */
+		Info4("setting option \"%s\" to {\"%s\",\"%s\",\"%s\"}",
+		      ent->desc->defname,
+		      opt->value.u_string/*multiaddr*/,
+		      opt->value2.u_string/*param2*/,
+		      opt->value3.u_string/*ifindex*/);
+	} else {
+		/*0 opt->value3.u_string = NULL; / * is NULL from init */
+		Info3("setting option \"%s\" to {\"%s\",\"%s\"}",
+		      ent->desc->defname,
+		      opt->value.u_string/*multiaddr*/,
+		      opt->value2.u_string/*param2*/);
+	}
+#else /* !HAVE_STRUCT_IP_MREQN */
+	Info3("setting option \"%s\" to {\"%s\",\"%s\"}",
+	      ent->desc->defname,
+	      opt->value.u_string/*multiaddr*/,
+	      opt->value2.u_string/*param2*/);
+#endif /* !HAVE_STRUCT_IP_MREQN */
+	return 0;
+}
+#endif /* defined(HAVE_STRUCT_IP_MREQ) || defined (HAVE_STRUCT_IP_MREQN) */
+
+#if defined(HAVE_STRUCT_IP_MREQ) || defined (HAVE_STRUCT_IP_MREQN)
+int xioapply_ip_add_membership(
+	xiosingle_t *xfd,
+	struct opt *opt)
+{
+	union {
+#if HAVE_STRUCT_IP_MREQN
+		struct ip_mreqn mreqn;
+#endif
+		struct ip_mreq  mreq;
+	} ip4_mreqn = {{{0}}};
+	/* IPv6 not supported - seems to have different handling */
+/*
+mc:addr:ifname|ifind
+mc:ifname|ifind
+mc:addr
+*/
+	union sockaddr_union sockaddr1;
+	socklen_t socklen1 = sizeof(sockaddr1.ip4);
+	union sockaddr_union sockaddr2;
+	socklen_t socklen2 = sizeof(sockaddr2.ip4);
+
+	/* first parameter is alway multicast address */
+	/*! result */
+	xiogetaddrinfo(opt->value.u_string/*multiaddr*/, NULL,
+		       xfd->para.socket.la.soa.sa_family,
+		       SOCK_DGRAM, IPPROTO_IP,
+		       &sockaddr1, &socklen1, 0, 0);
+	ip4_mreqn.mreq.imr_multiaddr = sockaddr1.ip4.sin_addr;
+	if (0) {
+		;	/* for canonical reasons */
+#if HAVE_STRUCT_IP_MREQN
+	} else if (opt->value3.u_string/*ifindex*/ != NULL) {
+		/* three parameters */
+		/* second parameter is interface address */
+		xiogetaddrinfo(opt->value2.u_string/*param2*/, NULL,
+			       xfd->para.socket.la.soa.sa_family,
+			       SOCK_DGRAM, IPPROTO_IP,
+			       &sockaddr2, &socklen2, 0, 0);
+		ip4_mreqn.mreq.imr_interface = sockaddr2.ip4.sin_addr;
+		/* third parameter is interface */
+		if (ifindex(opt->value3.u_string/*ifindex*/,
+			    (unsigned int *)&ip4_mreqn.mreqn.imr_ifindex, -1)
+		    < 0) {
+			Error1("cannot resolve interface \"%s\"",
+			       opt->value3.u_string/*ifindex*/);
+		}
+#endif /* HAVE_STRUCT_IP_MREQN */
+	} else {
+		/* two parameters */
+		if (0) {
+			;	/* for canonical reasons */
+#if HAVE_STRUCT_IP_MREQN
+			/* there is a form with two parameters that uses mreqn */
+		} else if (ifindex(opt->value2.u_string/*param2*/,
+				   (unsigned int *)&ip4_mreqn.mreqn.imr_ifindex,
+				   -1)
+			   >= 0) {
+			/* yes, second param converts to interface */
+			ip4_mreqn.mreq.imr_interface.s_addr = htonl(0);
+#endif /* HAVE_STRUCT_IP_MREQN */
+		} else {
+			/*! result */
+			xiogetaddrinfo(opt->value2.u_string/*param2*/, NULL,
+				       xfd->para.socket.la.soa.sa_family,
+				       SOCK_DGRAM, IPPROTO_IP,
+				       &sockaddr2, &socklen2, 0, 0);
+			ip4_mreqn.mreq.imr_interface = sockaddr2.ip4.sin_addr;
+		}
+	}
+
+#if LATER
+	if (0) {
+		; /* for canonical reasons */
+	} else if (xfd->para.socket.la.soa.sa_family == PF_INET) {
+	} else if (xfd->para.socket.la.soa.sa_family == PF_INET6) {
+		ip6_mreqn.mreq.imr_multiaddr = sockaddr1.ip6.sin6_addr;
+		ip6_mreqn.mreq.imr_interface = sockaddr2.ip6.sin6_addr;
+	}
+#endif
+
+#if HAVE_STRUCT_IP_MREQN
+	if (Setsockopt(xfd->fd, opt->desc->major, opt->desc->minor,
+		       &ip4_mreqn.mreqn, sizeof(ip4_mreqn.mreqn)) < 0) {
+		Error8("setsockopt(%d, %d, %d, {0x%08x,0x%08x,%d}, "F_Zu"): %s",
+		       xfd->fd, opt->desc->major, opt->desc->minor,
+		       ip4_mreqn.mreqn.imr_multiaddr.s_addr,
+		       ip4_mreqn.mreqn.imr_address.s_addr,
+		       ip4_mreqn.mreqn.imr_ifindex,
+		       sizeof(ip4_mreqn.mreqn),
+		       strerror(errno));
+		opt->desc = ODESC_ERROR;
+		return -1;
+	}
+#else
+	if (Setsockopt(xfd->fd, opt->desc->major, opt->desc->minor,
+		       &ip4_mreqn.mreq, sizeof(ip4_mreqn.mreq)) < 0) {
+		Error7("setsockopt(%d, %d, %d, {0x%08x,0x%08x}, "F_Zu"): %s",
+		       xfd->fd, opt->desc->major, opt->desc->minor,
+		       ip4_mreqn.mreq.imr_multiaddr,
+		       ip4_mreqn.mreq.imr_interface,
+		       sizeof(ip4_mreqn.mreq),
+		       strerror(errno));
+		opt->desc = ODESC_ERROR;
+		return -1;
+	}
+#endif
+	return 0;
+}
+#endif /* defined(HAVE_STRUCT_IP_MREQ) || defined (HAVE_STRUCT_IP_MREQN) */
+
+
 #if HAVE_STRUCT_IP_MREQ_SOURCE
 int xiotype_ip_add_source_membership(char *token, const struct optname *ent, struct opt *opt) {
    /* we do not resolve the addresses here because we do not yet know
@@ -688,7 +883,10 @@ int xiotype_ip_add_source_membership(char *token, const struct optname *ent, str
       Error1("syntax in option %s: missing ':'", token);
    }
    *buffp++ = '\0';
-   opt->value.u_ip_mreq_source.mcaddr = strdup(buff); /*!!! NULL */
+   if ((opt->value.u_string/*mcaddr*/ = strdup(buff)) == NULL) {
+      Error1("strdup(\"%s\"): out of memory", buff);
+      return -1;
+   }
 
    ++tokp;
    /* parse second IP address, expect ':' or '\0'' */
@@ -709,7 +907,11 @@ int xiotype_ip_add_source_membership(char *token, const struct optname *ent, str
       Error1("syntax in option %s: missing ':'", token);
    }
    *buffp++ = '\0';
-   opt->value.u_ip_mreq_source.ifaddr = strdup(buff); /*!!! NULL */
+   if ((opt->value2.u_string/*ifaddr*/ = strdup(buff)) == NULL) {
+      Error1("strdup(\"%s\"): out of memory", buff);
+      free(opt->value.u_string);
+      return -1;
+   }
 
    ++tokp;
    /* parse third IP address, expect ':' or '\0'' */
@@ -730,13 +932,18 @@ int xiotype_ip_add_source_membership(char *token, const struct optname *ent, str
       Error1("syntax in option %s: trailing cruft", token);
    }
    *buffp++ = '\0';
-   opt->value.u_ip_mreq_source.srcaddr = strdup(buff); /*!!! NULL */
+   if ((opt->value3.u_string/*srcaddr*/ = strdup(buff)) == NULL) {
+      Error1("strdup(\"%s\"): out of memory", buff);
+      free(opt->value.u_string);
+      free(opt->value2.u_string);
+      return -1;
+   }
 
    Info4("setting option \"%s\" to {0x%08x,0x%08x,0x%08x}",
 	 ent->desc->defname,
-	 ntohl(*(unsigned int *)opt->value.u_ip_mreq_source.mcaddr),
-	 ntohl(*(unsigned int *)opt->value.u_ip_mreq_source.ifaddr),
-	 ntohl(*(unsigned int *)opt->value.u_ip_mreq_source.srcaddr));
+	 ntohl(*(unsigned int *)opt->value.u_string/*mcaddr*/),
+	 ntohl(*(unsigned int *)opt->value2.u_string/*ifaddr*/),
+	 ntohl(*(unsigned int *)opt->value3.u_string/*srcaddr*/));
    return 0;
 }
 
@@ -752,19 +959,19 @@ int xioapply_ip_add_source_membership(struct single *xfd, struct opt *opt) {
 
    /* first parameter is always multicast address */
    /*! result */
-   xiogetaddrinfo(opt->value.u_ip_mreq_source.mcaddr, NULL,
+   xiogetaddrinfo(opt->value.u_string/*mcaddr*/, NULL,
 		  xfd->para.socket.la.soa.sa_family,
 		  SOCK_DGRAM, IPPROTO_IP,
 		  &sockaddr1, &socklen1, 0, 0);
    ip4_mreq_src.imr_multiaddr = sockaddr1.ip4.sin_addr;
    /* second parameter is interface address */
-   xiogetaddrinfo(opt->value.u_ip_mreq_source.ifaddr, NULL,
+   xiogetaddrinfo(opt->value2.u_string/*ifaddr*/, NULL,
 		  xfd->para.socket.la.soa.sa_family,
 		  SOCK_DGRAM, IPPROTO_IP,
 		  &sockaddr2, &socklen2, 0, 0);
    ip4_mreq_src.imr_interface = sockaddr2.ip4.sin_addr;
    /* third parameter is source address */
-   xiogetaddrinfo(opt->value.u_ip_mreq_source.srcaddr, NULL,
+   xiogetaddrinfo(opt->value3.u_string/*srcaddr*/, NULL,
 		  xfd->para.socket.la.soa.sa_family,
 		  SOCK_DGRAM, IPPROTO_IP,
 		  &sockaddr3, &socklen3, 0, 0);
diff --git a/xio-ip.h b/xio-ip.h
index 8b3c922..ad6c8cb 100644
--- a/xio-ip.h
+++ b/xio-ip.h
@@ -49,6 +49,8 @@ int xiolog_ancillary_ip(struct cmsghdr *cmsg, int *num,
 			char *nambuff, int namlen,
 			char *envbuff, int envlen,
 			char *valbuff, int vallen);
+extern int xiotype_ip_add_membership(char *token, const struct optname *ent, struct opt *opt);
+extern int xioapply_ip_add_membership(xiosingle_t *xfd, struct opt *opt);
 extern int xiotype_ip_add_source_membership(char* token, const struct optname *ent, struct opt *opt);
 extern int xioapply_ip_add_source_membership(struct single *xfd, struct opt *opt);
 
diff --git a/xio-ip6.c b/xio-ip6.c
index 98e5c7a..682f62a 100644
--- a/xio-ip6.c
+++ b/xio-ip6.c
@@ -81,6 +81,7 @@ const struct optdesc opt_ipv6_recvpathmtu = { "ipv6-recvpathmtu", "recvpathmtu",
 int xioip6_pton(const char *src, struct in6_addr *dst) {
    union sockaddr_union sockaddr;
    socklen_t sockaddrlen = sizeof(sockaddr);
+   int res;
 
    if (src[0] == '[') {
       char plainaddr[INET6_ADDRSTRLEN];
@@ -92,8 +93,9 @@ int xioip6_pton(const char *src, struct in6_addr *dst) {
 	 *clos = '\0';
       return xioip6_pton(plainaddr, dst);
    }
-   if (xiogetaddrinfo(src, NULL, PF_INET6, 0, 0, &sockaddr, &sockaddrlen,
-		      0, 0)
+   if ((res =
+	xiogetaddrinfo(src, NULL, PF_INET6, 0, 0, &sockaddr, &sockaddrlen,
+			     0, 0))
        != STAT_OK) {
       return STAT_NORETRY;
    }
@@ -457,4 +459,47 @@ xiosetsockaddrenv_ip6(int idx, char *namebuff, size_t namelen,
    return -1;
 }
 
+
+#if defined(HAVE_STRUCT_IPV6_MREQ)
+int xioapply_ipv6_join_group(
+	xiosingle_t *xfd,
+	struct opt *opt)
+{
+	struct ipv6_mreq ip6_mreq = {{{{0}}}};
+	union sockaddr_union sockaddr1;
+	socklen_t socklen1 = sizeof(sockaddr1.ip6);
+	int res;
+
+	/* Always two parameters */
+	/* First parameter is multicast address */
+	if ((res =
+	     xiogetaddrinfo(opt->value.u_string/*multiaddr*/, NULL,
+			    xfd->para.socket.la.soa.sa_family,
+			    SOCK_DGRAM, IPPROTO_IP,
+			    &sockaddr1, &socklen1, 0, 0)) != STAT_OK) {
+	   return res;
+	}
+	ip6_mreq.ipv6mr_multiaddr = sockaddr1.ip6.sin6_addr;
+	if (ifindex(opt->value2.u_string/*param2*/,
+		    &ip6_mreq.ipv6mr_interface, -1)
+	    < 0) {
+		Error1("interface \"%s\" not found",
+		       opt->value2.u_string/*param2*/);
+		ip6_mreq.ipv6mr_interface = htonl(0);
+	}
+
+	if (Setsockopt(xfd->fd, opt->desc->major, opt->desc->minor,
+		       &ip6_mreq, sizeof(ip6_mreq)) < 0) {
+		Error6("setsockopt(%d, %d, %d, {...,0x%08x}, "F_Zu"): %s",
+		       xfd->fd, opt->desc->major, opt->desc->minor,
+		       ip6_mreq.ipv6mr_interface,
+		       sizeof(ip6_mreq),
+		       strerror(errno));
+		opt->desc = ODESC_ERROR;
+		return -1;
+	}
+	return 0;
+}
+#endif /* defined(HAVE_STRUCT_IPV6_MREQ) */
+
 #endif /* WITH_IP6 */
diff --git a/xio-ip6.h b/xio-ip6.h
index e99e559..6da27e1 100644
--- a/xio-ip6.h
+++ b/xio-ip6.h
@@ -48,6 +48,7 @@ extern int
 xiosetsockaddrenv_ip6(int idx, char *namebuff, size_t namelen,
 		      char *valuebuff, size_t valuelen,
 		      struct sockaddr_in6 *sa, int ipproto);
+extern int xioapply_ipv6_join_group(xiosingle_t *xfd, struct opt *opt);
 
 #endif /* WITH_IP6 */
 
diff --git a/xio.h b/xio.h
index 80fdfce..4e5bc49 100644
--- a/xio.h
+++ b/xio.h
@@ -375,22 +375,6 @@ union integral {
 #if HAVE_STRUCT_TIMESPEC
    struct timespec u_timespec;
 #endif /* HAVE_STRUCT_TIMESPEC */
-#if HAVE_STRUCT_IP_MREQ || HAVE_STRUCT_IP_MREQN
-   struct {
-      char *multiaddr;
-      char *param2;	/* address, interface */
-#if HAVE_STRUCT_IP_MREQN
-      char ifindex[IF_NAMESIZE+1];
-#endif
-   } u_ip_mreq;
-#endif
-#if HAVE_STRUCT_IP_MREQ_SOURCE
-   struct {
-      char *mcaddr;
-      char *ifaddr;	/* address, interface */
-      char *srcaddr;	/* source address */
-   } u_ip_mreq_source;
-#endif
 #if WITH_IP4
    struct in_addr  u_ip4addr;
 #endif
diff --git a/xioopts.c b/xioopts.c
index 73dac1b..64a4793 100644
--- a/xioopts.c
+++ b/xioopts.c
@@ -2477,76 +2477,10 @@ int parseopts_table(const char **a, groups_t groups, struct opt **opts,
 	       (*opts)[i].value.u_int, (*opts)[i].value2.u_int,
 	       (*opts)[i].value3.u_string);
 	 break;
+
 #if defined(HAVE_STRUCT_IP_MREQ) || defined (HAVE_STRUCT_IP_MREQN)
-
       case TYPE_IP_MREQN:
-	 {
-	    /* we do not resolve the addresses here because we do not yet know
-	       if we are coping with a IPv4 or IPv6 socat address */
-	    const char *ends[] = { ":", NULL };
-	    const char *nests[] = { "[","]", NULL };
-	    char buff[512], *buffp=buff; size_t bufspc = sizeof(buff)-1;
-
-	    /* parse first IP address, expect ':' */
-	    tokp = token;
-	    /*! result= */
-	    parsres =
-	       nestlex((const char **)&tokp, &buffp, &bufspc,
-		       ends, NULL, NULL, nests,
-		       true, false, false);
-	    if (parsres < 0) {
-	       Error1("option too long:  \"%s\"", *a);
-	       return -1;
-	    } else if (parsres > 0) {
-	       Error1("syntax error in \"%s\"", *a);
-	       return -1;
-	    }
-	    if (*tokp != ':') {
-	       Error1("syntax in option %s: missing ':'", token);
-	    }
-	    *buffp++ = '\0';
-	    (*opts)[i].value.u_ip_mreq.multiaddr = strdup(buff); /*!!! NULL */
-
-	    ++tokp;
-	    /* parse second IP address, expect ':' or '\0'' */
-	    buffp = buff;
-	    /*! result= */
-	    parsres =
-	       nestlex((const char **)&tokp, &buffp, &bufspc,
-		       ends, NULL, NULL, nests,
-		       true, false, false);
-	    if (parsres < 0) {
-	       Error1("option too long:  \"%s\"", *a);
-	       return -1;
-	    } else if (parsres > 0) {
-	       Error1("syntax error in \"%s\"", *a);
-	       return -1;
-	    }
-	    *buffp++ = '\0';
-	    (*opts)[i].value.u_ip_mreq.param2 = strdup(buff); /*!!! NULL */
-
-#if HAVE_STRUCT_IP_MREQN
-	    if (*tokp++ == ':') {
-	       strncpy((*opts)[i].value.u_ip_mreq.ifindex, tokp, IF_NAMESIZE);	/* ok */
-	       Info4("setting option \"%s\" to {\"%s\",\"%s\",\"%s\"}",
-		     ent->desc->defname,
-		     (*opts)[i].value.u_ip_mreq.multiaddr,
-		     (*opts)[i].value.u_ip_mreq.param2,
-		     (*opts)[i].value.u_ip_mreq.ifindex);
-	    } else {
-	       (*opts)[i].value.u_ip_mreq.ifindex[0] = '\0';
-	       Info3("setting option \"%s\" to {\"%s\",\"%s\"}",
-		     ent->desc->defname,
-		     (*opts)[i].value.u_ip_mreq.multiaddr,
-		     (*opts)[i].value.u_ip_mreq.param2);
-	    }
-#else /* !HAVE_STRUCT_IP_MREQN */
-	    Info3("setting option \"%s\" to {0x%08x,0x%08x}",
-		  ent->desc->defname,
-		  (*opts)[i].value.u_ip_mreq.multiaddr,
-		  (*opts)[i].value.u_ip_mreq.param2);
-#endif /* !HAVE_STRUCT_IP_MREQN */
-	 }
+	 xiotype_ip_add_membership(token, ent, opt);
 	 break;
 #endif /* defined(HAVE_STRUCT_IP_MREQ) || defined (HAVE_STRUCT_IP_MREQN) */
 
@@ -4029,110 +3963,10 @@ int applyopts_single(struct single *xfd, struct opt *opts, enum e_phase phase) {
 	 switch (opt->desc->optcode) {
 #if WITH_IP4 && (defined(HAVE_STRUCT_IP_MREQ) || defined (HAVE_STRUCT_IP_MREQN))
 	 case OPT_IP_ADD_MEMBERSHIP:
-	    {
-	       union {
-#if HAVE_STRUCT_IP_MREQN
-		  struct ip_mreqn mreqn;
-#endif
-		  struct ip_mreq  mreq;
-	       } ip4_mreqn = {{{0}}};
-	       /* IPv6 not supported - seems to have different handling */
-/*
-mc:addr:ifname|ifind
-mc:ifname|ifind
-mc:addr
-*/
-	       union sockaddr_union sockaddr1;
-	       socklen_t socklen1 = sizeof(sockaddr1.ip4);
-	       union sockaddr_union sockaddr2;
-	       socklen_t socklen2 = sizeof(sockaddr2.ip4);
-
-	       /* first parameter is alway multicast address */
-	       /*! result */
-	       xiogetaddrinfo(opt->value.u_ip_mreq.multiaddr, NULL,
-			      xfd->para.socket.la.soa.sa_family,
-			      SOCK_DGRAM, IPPROTO_IP,
-			      &sockaddr1, &socklen1, 0, 0);
-	       ip4_mreqn.mreq.imr_multiaddr = sockaddr1.ip4.sin_addr;
-	       if (0) {
-		  ;	/* for canonical reasons */
-#if HAVE_STRUCT_IP_MREQN
-	       } else if (opt->value.u_ip_mreq.ifindex[0] != '\0') {
-		  /* three parameters */
-		  /* second parameter is interface address */
-		  xiogetaddrinfo(opt->value.u_ip_mreq.param2, NULL,
-				 xfd->para.socket.la.soa.sa_family,
-				 SOCK_DGRAM, IPPROTO_IP,
-				 &sockaddr2, &socklen2, 0, 0);
-		  ip4_mreqn.mreq.imr_interface = sockaddr2.ip4.sin_addr;
-		  /* third parameter is interface */
-		  if (ifindex(opt->value.u_ip_mreq.ifindex,
-			      (unsigned int *)&ip4_mreqn.mreqn.imr_ifindex, -1)
-		      < 0) {
-		     Error1("cannot resolve interface \"%s\"",
-			    opt->value.u_ip_mreq.ifindex);
-		  }
-#endif /* HAVE_STRUCT_IP_MREQN */
-	       } else {
-		  /* two parameters */
-		  if (0) {
-		     ;	/* for canonical reasons */
-#if HAVE_STRUCT_IP_MREQN
-		  /* there is a form with two parameters that uses mreqn */
-		  } else if (ifindex(opt->value.u_ip_mreq.param2,
-				     (unsigned int *)&ip4_mreqn.mreqn.imr_ifindex,
-				     -1)
-			     >= 0) {
-		     /* yes, second param converts to interface */
-		     ip4_mreqn.mreq.imr_interface.s_addr = htonl(0);
-#endif /* HAVE_STRUCT_IP_MREQN */
-		  } else {
-		     /*! result */
-		     xiogetaddrinfo(opt->value.u_ip_mreq.param2, NULL,
-				    xfd->para.socket.la.soa.sa_family,
-				    SOCK_DGRAM, IPPROTO_IP,
-				    &sockaddr2, &socklen2, 0, 0);
-		     ip4_mreqn.mreq.imr_interface = sockaddr2.ip4.sin_addr;
-		  }
-	       }
-
-#if LATER
-	       if (0) {
-		  ; /* for canonical reasons */
-	       } else if (xfd->para.socket.la.soa.sa_family == PF_INET) {
-	       } else if (xfd->para.socket.la.soa.sa_family == PF_INET6) {
-		  ip6_mreqn.mreq.imr_multiaddr = sockaddr1.ip6.sin6_addr;
-		  ip6_mreqn.mreq.imr_interface = sockaddr2.ip6.sin6_addr;
-	       }
-#endif
-
-#if HAVE_STRUCT_IP_MREQN
-	       if (Setsockopt(xfd->fd, opt->desc->major, opt->desc->minor,
-			      &ip4_mreqn.mreqn, sizeof(ip4_mreqn.mreqn)) < 0) {
-		  Error8("setsockopt(%d, %d, %d, {0x%08x,0x%08x,%d}, "F_Zu"): %s",
-			 xfd->fd, opt->desc->major, opt->desc->minor,
-			 ip4_mreqn.mreqn.imr_multiaddr.s_addr,
-			 ip4_mreqn.mreqn.imr_address.s_addr,
-			 ip4_mreqn.mreqn.imr_ifindex,
-			 sizeof(ip4_mreqn.mreqn),
-			 strerror(errno));
-		  opt->desc = ODESC_ERROR; continue;
-	       }
-#else
-	       if (Setsockopt(xfd->fd, opt->desc->major, opt->desc->minor,
-			      &ip4_mreqn.mreq, sizeof(ip4_mreqn.mreq)) < 0) {
-		  Error7("setsockopt(%d, %d, %d, {0x%08x,0x%08x}, "F_Zu"): %s",
-			 xfd->fd, opt->desc->major, opt->desc->minor,
-			 ip4_mreqn.mreq.imr_multiaddr,
-			 ip4_mreqn.mreq.imr_interface,
-			 sizeof(ip4_mreqn.mreq),
-			 strerror(errno));
-		  opt->desc = ODESC_ERROR; continue;
-	       }
-#endif
-	       break;
+	    if (xioapply_ip_add_membership(xfd, opt) < 0) {
+	       continue;
 	    }
-	   break;
+	    break;
 #endif /* WITH_IP4 && (defined(HAVE_STRUCT_IP_MREQ) || defined (HAVE_STRUCT_IP_MREQN)) */
 
 #if WITH_IP4 && defined(HAVE_STRUCT_IP_MREQ_SOURCE) && defined(IP_ADD_SOURCE_MEMBERSHIP)
@@ -4140,43 +3974,15 @@ mc:addr
 	    if (xioapply_ip_add_source_membership(xfd, opt) < 0) {
 	       continue;
 	    }
-	   break;
+	    break;
 #endif /* WITH_IP4 && defined(HAVE_STRUCT_IP_MREQ_SOURCE) && defined(IP_ADD_SOURCE_MEMBERSHIP) */
 
 #if WITH_IP6 && defined(HAVE_STRUCT_IPV6_MREQ)
 	 case OPT_IPV6_JOIN_GROUP:
-	    {
-	       struct ipv6_mreq ip6_mreq = {{{{0}}}};
-	       union sockaddr_union sockaddr1;
-	       socklen_t socklen1 = sizeof(sockaddr1.ip6);
-
-	       /* always two parameters */
-	       /* first parameter is multicast address */
-	       /*! result */
-	       xiogetaddrinfo(opt->value.u_ip_mreq.multiaddr, NULL,
-			      xfd->para.socket.la.soa.sa_family,
-			      SOCK_DGRAM, IPPROTO_IP,
-			      &sockaddr1, &socklen1, 0, 0);
-	       ip6_mreq.ipv6mr_multiaddr = sockaddr1.ip6.sin6_addr;
-	       if (ifindex(opt->value.u_ip_mreq.param2,
-			   &ip6_mreq.ipv6mr_interface, -1)
-		   < 0) {
-		  Error1("interface \"%s\" not found",
-			 opt->value.u_ip_mreq.param2);
-		  ip6_mreq.ipv6mr_interface = htonl(0);
-	       }
-
-	       if (Setsockopt(xfd->fd, opt->desc->major, opt->desc->minor,
-			      &ip6_mreq, sizeof(ip6_mreq)) < 0) {
-		  Error6("setsockopt(%d, %d, %d, {...,0x%08x}, "F_Zu"): %s",
-			 xfd->fd, opt->desc->major, opt->desc->minor,
-			 ip6_mreq.ipv6mr_interface,
-			 sizeof(ip6_mreq),
-			 strerror(errno));
-		  opt->desc = ODESC_ERROR; continue;
-	       }
+	    if (xioapply_ipv6_join_group(xfd, opt) < 0) {
+	       continue;
 	    }
-	   break;
+	    break;
 #endif /* WITH_IP6 && defined(HAVE_STRUCT_IPV6_MREQ) */
 	default:
 	   /* ignore here */