update s function

bashrc

@@ -374,6 +374,11 @@ s(){
         ack --pager="$PAGER" "$@"
     else
         echo ">> Using grep" 1>&2
+        if test $# -eq 0
+        then
+            echo "No search word given." 1>&2
+            return 1
+        fi
         grep -nH --color=always --exclude='.svn/*' --exclude='.git/*' "$@" -r . \
             | $PAGER
         # echo "No search command found. Use grep." 2>&1