Create and switch sessions in tmux quickly

tm.sh

#!/bin/sh
tm() {
  if [ -z $1 ]; then
    tmux switch-client -l
  else
    if [ -z "$TMUX" ]; then
      tmux new-session -As $1
    else
      if ! tmux has-session -t $1 2>/dev/null; then
        TMUX= tmux new-session -ds $1
      fi
      tmux switch-client -t $1
    fi
  fi
}

tm $1

tm_tab_complete.bash

# tmux session tab complete function
_tmux_complete_session() {
  local IFS=$'\n'
  local cur=${COMP_WORDS[COMP_CWORD]}
  COMPREPLY=( ${COMPREPLY[@]:-} $(compgen -W "$(tmux -q list-sessions | cut -f 1 -d ':')" -- "${cur}") )
}
complete -F _tmux_complete_session tm

tmux.conf

# Toggle between the last two sessions
bind m switch-client -l
bind M command-prompt -p 'switch session:' "run \"tm '%%'\""

tm mysession

Whether or not you are in tmux, the tm function will switch to the given session if it already exists. If it doesn't already exist, it will create it and then switch to it.

Source the second file for bash tab-completions of all existing session names.

I found the basics of this function somewhere on the internet. Apologies to the original author, but I can't find it anymore.

Is there a reason you're not using Tmuxinator for this? Lovin' the autocomplete for it though 😄

Because 14 lines are better than a gem?

Yeah, I'm not looking for "session management". I just want to be able to switch without thinking.

Updated: Now by running tm with no arguments you can switch to the previous session. Running tm over and over will toggle you between two sessions.

Bonus: C-a m in tmux will do the same thing. C-a M will let you name a session. I found this useful today, as I have a fleet of Rails servers running. Those are in one session and I do my development in another. This lets me create and destroy windows without worrying about being tangled up with the one running the servers, but I can still check on them easily if I need to.

Ok, so that was dumb. @calebthompson let me know about tmux switch-client -l which does the same thing as the empty tm command. ahem So I changed that.

Zsh completion:

#compdef tm

_arguments "1: :(`tmux list-sessions -F'#S'`)"

# vim: filetype=zsh

Put that in a file called _tm somewhere in your fpath. I put mine in ~/.dotfiles/zsh/completions/_tm.

You'll need to run autoload -U compinit and compinit after _tm is added to your fpath in your .zshrc or wherever.

#!/bin/zsh

WORKING_DIRECTORY=$(cdpath=(. ~/code) cd $1 > /dev/null 2>&1 && pwd)
if [ -z "$TMUX" ]; then
  # not in tmux
  if [ -n "$WORKING_DIRECTORY" ]; then
    tmux new-session -As $1 -c $WORKING_DIRECTORY
  else
    tmux new-session -As $1 -c $HOME
  fi
else
  # inside tmux
  if tmux has-session -t $1 2> /dev/null; then
    tmux switch-client -t $1
  else
    if [ -n "$WORKING_DIRECTORY" ]; then
      TMUX= tmux new-session -ds $1 -c $WORKING_DIRECTORY
    else
      TMUX= tmux new-session -ds $1
    fi
    tmux switch-client -t $1
  fi
fi

Updated to automatically set the working directory (for the initial and successive windows) of new sessions to project folders, assuming that they live in ~/code. The cdpath portion of line 3 could be removed if you actually use cdpath.

No longer works with only sh.

Jon do you think it's time to move this to a project with a proper homebrew package and stuff?