tmux/Option/status-left

• status-left

  • A tmux session option holding the format string drawn at the left end of the tmux/Status Line. The default is [#{session_name}] , which is how the tmux/session/Name comes to sit there.
  • The string is expanded as a format and passed through strftime(3), so date and time specifiers work inside it.
  • Its width is bounded by tmux/Option/status-left-length.

  • Usage

    • Show the raw format string:
      • sh

        tmux show-options -gv status-left

    • Expand it uncapped, and measure the columns it wants:
      • sh

        tmux display-message -p '#{T:status-left}'
        tmux display-message -p '#{w:#{T:status-left}}'

    • Spend every column on the name by dropping the brackets:
      • sh

        set -g status-left '#{session_name} '

  • Per-cell width inside the format

    • A =N: limit written inside the format string bounds a single cell on its own, independent of status-left-length: #{=20:session_name} shows at most twenty characters of the name however high the length cap goes. Raising the length cap while such a limit is in place changes nothing.
    • The stock status-left carries no per-cell limit, so status-left-length is the only bound on the session name. tmux/Option/status-right is the contrasting case — its default does cap a cell this way.