improve help

tmuxssh

@@ -1,6 +1,21 @@
 #!/bin/bash
 
-HOSTS=( vm3 vm4 vm5 vm6 vm7 vm8 vm9 vm10 )
+
+HELP="
+Arguments: hostnames, or  username@hostnames
+ ctrl-b m to toggle pane synchronization
+ ctrl-b arrows to move between tiles
+
+"
+[[ -z "$1" ]] && { 
+ echo "$HELP"
+ exit 
+}
+[[ "$1" = "-h" ]] && { 
+ echo "$HELP"
+ exit 
+} 
+
 
 tmux new-session -d -s ssh$USER 'ssh '$1
 tmux set-window-option -t:0 synchronize-panes on
@@ -13,5 +28,3 @@ done
 
 tmux -2 attach-session -t ssh$USER
 
-echo "ctrl-b m to toggle pane synchronization"
-echo "ctrl-b arrows to move between tiles"