diff --git a/assets/default/dotfiles/tmux.conf b/assets/default/dotfiles/tmux.conf
index b0d5a3f..7c4e524 100644
--- a/assets/default/dotfiles/tmux.conf
+++ b/assets/default/dotfiles/tmux.conf
@@ -6,7 +6,7 @@ set-option -g set-titles on
 set-option -g set-titles-string '[#S:#I] #W'
 
 # copy and paster
-set-option -g default-command "reattach-to-user-namespace-tmux bash"
+if-shell 'test "$(uname -s)" = "Darwin"' 'set-option -g default-command "reattach-to-user-namespace-tmux bash"'
 
 # look good
 set -g default-terminal "screen-256color"
@@ -30,10 +30,12 @@ setw -g mouse-select-pane on
 if-shell "vertest `tmux -V` '>=' 1.9" 'bind | split-window -h -c "#{pane_current_path}"'
 if-shell "vertest `tmux -V` '>=' 1.9" 'bind - split-window -c "#{pane_current_path}"'
 if-shell "vertest `tmux -V` '>=' 1.9" 'bind _ split-window -c "#{pane_current_path}"'
-# old versions
-if-shell "vertest `tmux -V` '<' 1.9" 'bind | split-window -h'
-if-shell "vertest `tmux -V` '<' 1.9" 'bind - split-window'
-if-shell "vertest `tmux -V` '<' 1.9" 'bind _ split-window'
+# old versions (some won't recognize new vertest function"
+if-shell "vertest `tmux -V` '<' 1.9 || [ $? -eq 127 ]" 'bind | split-window -h'
+if-shell "vertest `tmux -V` '<' 1.9 || [ $? -eq 127 ]" 'bind - split-window'
+if-shell "vertest `tmux -V` '<' 1.9 || [ $? -eq 127 ]" 'bind _ split-window'
+
+run-shell "source ./.bash_funcs && vertest `tmux -V` '>' 1.9 && touch tmux.true || touch tmux.false"
 
 # act like vim
 setw -g mode-keys vi