guard use of IP_RECVTOS which is unavailable on kfreebsd

diff --git a/src/liboping.c b/src/liboping.c
index 83ca9c2..76a7d53 100644 (file)
--- a/src/liboping.c
+++ b/src/liboping.c
@@ -1540,10 +1540,12 @@ int ping_host_add (pingobj_t *obj, const char *host)
                {
                        int opt;
 
+#ifdef IP_RECVTOS
                        /* Enable receiving the TOS field */
                        opt = 1;
                        setsockopt (ph->fd, IPPROTO_IP, IP_RECVTOS,
                                        &opt, sizeof (opt));
+#endif /* IP_RECVTOS */
 
                        /* Enable receiving the TTL field */
                        opt = 1;