dont show json option if not available

diff --git a/ui/mtr.c b/ui/mtr.c
index 6fd0d70ec752d59e9f95f7f6d32271b12815889d..2c6fc68d239c4d8759f70787c518fcdd74ee064b 100644 (file)
--- a/ui/mtr.c
+++ b/ui/mtr.c
@@ -142,7 +142,9 @@ static void __attribute__ ((__noreturn__)) usage(FILE * out)
     fputs(" -w, --report-wide          output wide report\n", out);
     fputs(" -c, --report-cycles COUNT  set the number of pings sent\n",
           out);
+#ifdef HAVE_JANSSON
     fputs(" -j, --json                 output json\n", out);
+#endif
     fputs(" -x, --xml                  output xml\n", out);
     fputs(" -C, --csv                  output comma separated values\n",
           out);