1 files changed, 5 insertions, 0 deletions
diff --git a/xalarm b/xalarm
index 399e4e6..63baf43 100755
--- a/xalarm
+++ b/xalarm
@@ -20,6 +20,11 @@ function xalarm_set {
   shift
   MESSAGE="${*:-Alarm!}"
 
+  # Simple argument checking
+  if ! echo $DELAY | grep -q '^[0-9]'; then
+    xalarm_usage
+  fi
+
   # Suppor for HH:MM format
   if echo $DELAY | grep -q '[0-9]:[0-9][0-9]'; then
     NOW="`date +%s`"