[Fix #55] Use a tmux daemon session

plugins/tmux/init.zsh

@@ -21,15 +21,23 @@ alias tl="tmux list-sessions"
 
 # Auto Start
 if [[ -z "$TMUX" ]] && zstyle -t ':omz:plugin:tmux:auto' start; then
-  session="$(
-    tmux list-sessions 2> /dev/null \
-      | cut -d':' -f1 \
-      | head -1)"
-
-  if [[ -n "$session" ]]; then
-    exec tmux attach-session -t "$session"
-  else
-    exec tmux new-session
+  tmux_session='#OMZ'
+
+  if ! tmux has-session -t "$tmux_session" 2> /dev/null; then
+    # Disable the destruction of unattached sessions globally.
+    tmux set-option -g destroy-unattached off &> /dev/null
+
+    # Create a new session.
+    tmux new-session -d -s "$tmux_session"
+
+    # Disable the destruction of the new, unattached session.
+    tmux set-option -t "$tmux_session" destroy-unattached off &> /dev/null
+
+    # Enable the destruction of unattached sessions globally to prevent
+    # an abundance of open, detached sessions.
+    tmux set-option -g destroy-unattached on &> /dev/null
   fi
+
+  exec tmux new-session -t "$tmux_session"
 fi