network plugin: Print a warning when setting the interface on a unicast socket is...

diff --git a/src/network.c b/src/network.c
index 9cb8c38..af4a117 100644 (file)
--- a/src/network.c
+++ b/src/network.c
@@ -1653,6 +1653,7 @@ static int network_set_interface (const sockent_t *se, const struct addrinfo *ai
                }
        }
 
+       /* else: Not a multicast interface. */
 #if defined(HAVE_IF_INDEXTONAME) && HAVE_IF_INDEXTONAME && defined(SO_BINDTODEVICE)
        if (se->interface != 0)
        {
@@ -1673,7 +1674,18 @@ static int network_set_interface (const sockent_t *se, const struct addrinfo *ai
                        return (-1);
                }
        }
-#endif /* HAVE_IF_INDEXTONAME && SO_BINDTODEVICE */
+/* #endif HAVE_IF_INDEXTONAME && SO_BINDTODEVICE */
+
+#else
+       WARNING ("network plugin: Cannot set the interface on a unicast "
+                       "socket because "
+# if !defined(SO_BINDTODEVICE)
+                       "the the \"SO_BINDTODEVICE\" socket option "
+# else
+                       "the \"if_indextoname\" function "
+# endif
+                       "is not available on your system.");
+#endif
 
        return (0);
 } /* }}} network_set_interface */