How to set up tmux so that it starts up with specified windows opened?

How to set up tmux so that it starts up with specified windows opened?

You can write a small shell script that launches tmux with the required programs. I have the following in a shell script that I call dev-tmux. A dev environment:

#!/bin/sh
tmux new-session -d 'vim'
tmux split-window -v 'ipython'
tmux split-window -h
tmux new-window 'mutt'
tmux -2 attach-session -d

So everytime I want to launch my favorite dev environment I can just do

$ dev-tmux

I was trying to create a complex grid of panes and had to deal with switching and splitting panes over and over again. Here are my learnings:

tmux new-session \;

Gets you started with a new session. To split it horizontal or vertical use split-window -h or -v subsequently, like that:

tmux new-session \; split-window -v \; split-window -h \;

Creates 3 panes, like this:

------------
|          |
|----------|
|    |     |
------------

To run commands in that panes, just add them with the send-keys 'my-command' command and C-m which executes it:

tmux new-session \; \
  send-keys 'tail -f /var/log/monitor.log' C-m \; \
  split-window -v \; \
  split-window -h \; \
  send-keys 'top' C-m \; 

And the resulting session should look like that.

------------
|  tail    |
|----------|
|    | top |
------------

Now I tried to again sub-divide the bottom left pane, so switching either back using last-pane, or in more complex windows, with the select-pane -t 1 where 1 is the number of the pane in order created starting with 0.

tmux new-session \; \
  send-keys 'tail -f /var/log/monitor.log' C-m \; \
  split-window -v \; \
  split-window -h \; \
  send-keys 'top' C-m \; \
  select-pane -t 1 \; \
  split-window -v \; \
  send-keys 'weechat' C-m \;

Does that. Basicaly knowing your way around with split-window and select-pane is all you need. It's also handy to pass with -p 75 a percentage size of the pane created by split-window to have more control over the size of the panes.

tmux new-session \; \
  send-keys 'tail -f /var/log/monitor.log' C-m \; \
  split-window -v -p 75 \; \
  split-window -h -p 30 \; \
  send-keys 'top' C-m \; \
  select-pane -t 1 \; \
  split-window -v \; \
  send-keys 'weechat' C-m \;

Which results in a session looking like that

------------------
|      tail      |
|----------------|
|          | top |
|----------|     |
| weechat  |     |
------------------

Hope that helps tmux enthusiasts in the future.

You can source different sessions from your .tmux.conf like so:

# initialize sessions
bind S source-file ~/.tmux/session1 
bind s source-file ~/.tmux/session2

And then format the sessions as you require:

#session1
new  -s SessionName -n WindowName Command
neww -n foo/bar foo
splitw -v -p 50 -t 0 bar
selectw -t 1 
selectp -t 0

This would open 2 windows, the second of which would be named foo/bar and would be split vertically in half (50%) with foo running above bar. Focus would be in window 2 (foo/bar), top pane (foo).

You can then start your preferred tmux session (in this case, session1) with PrefixShifts

Use tmuxinator - it allows you to have multiple sessions configured, and you can choose which one to launch at any given time. You can launch commands in particular windows or panes and give titles to windows. Here is an example use with developing Django applications.

Sample config file:

# ~/.tmuxinator/project_name.yml
# you can make as many tabs as you wish...

project_name: Tmuxinator
project_root: ~/code/rails_project
socket_name: foo # Not needed. Remove to use default socket
rvm: 1.9.2@rails_project
pre: sudo /etc/rc.d/mysqld start
tabs:
  - editor:
      layout: main-vertical
      panes:
        - vim
        - #empty, will just run plain bash
        - top
  - shell: git pull
  - database: rails db
  - server: rails s
  - logs: tail -f logs/development.log
  - console: rails c
  - capistrano:
  - server: ssh me@myhost

See the README at the above link for a full explanation.