From 96bee673945e1244023ddbc7dd8a9725eab50f34 Mon Sep 17 00:00:00 2001
From: Paul Gear <github@libertysys.com.au>
Date: Sat, 13 Jun 2015 15:22:43 +1000
Subject: [PATCH] Do not attempt to create file if there are no DS definitions

---
 includes/polling/functions.inc.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/includes/polling/functions.inc.php b/includes/polling/functions.inc.php
index b01d03e80..77e7d7825 100644
--- a/includes/polling/functions.inc.php
+++ b/includes/polling/functions.inc.php
@@ -359,7 +359,7 @@ function rrd_create_update($device, $name, $def, $val, $step = 300)
     global $config;
     $rrd = implode("/", array($config['rrd_dir'], $device['hostname'], safename(implode("-", $name)).".rrd"));
 
-    if (!is_file($rrd)) {
+    if (!is_file($rrd) && $def != null) {
         // add the --step and the rra definitions to the array
         $newdef = "--step $step ".implode(' ', $def).$config['rrd_rra'];
         d_echo("Creating RRD $rrd: $newdef");