Test xtitle availability on window_title

diff --git a/shell b/shell
index 4c4321af0625c9b1b52d6703e4bc9f3bef094290..9ecac83a8bbaff2237a497f15154822ce814eafe 100755 (executable)
--- a/shell
+++ b/shell
@@ -14,7 +14,9 @@ function window_title {
   if [ -n "$STY" ]; then
     screen -p $WINDOW -X title "$*"
   else
-    xtitle "$*"
+    if which xtitle &> /dev/null; then
+      xtitle "$*"
+    fi
   fi
 }