Tmux - A Great Terminal Multiplexer

The cons of VNC:

1. Depends on X (GUI environment).
2. Consume more CPU and network traffic (I think).
3. Can not resize the desktop (Latest realvnc can).
4. Does not tile (To be accurate, you can start a tiling WM in VNC. Average engineers just don't bother or able to do that).
5. Non-native windows that response slowly

The pros of VNC:

1. Uses dedicated password instead of login/password for sharing
2. Supports X applications

Tmux is kind of the next-gen of screen. People say tmux is superior since it

1. Is easier to configure.
2. Is easier to split window and change layout.
3. Is able to resize window.
4. Is easier to scripting.
5. Cleaner architecture, code, document etc.

I prefer "putty + tmux + to" since, as far as I know, secureCRT

1. can not detach/attach
2. can not group windows per projects(or bug/escalation etc.)
3. can not remote share
4. can not tile (?)
5. seems it does not support UTF-8
6. not convenient if the host list is really long
7. can not jump to destination host via an intermediate server
8. your hot-keys is not available other PCs, or after re-install
9. non-free

• Network unstable?
• Has to bring laptop home or meeting room?
• Laptop crashed?
• Mistakenly closed the terminal?

Does NOT matter! just re-attach.

This is a window auto-resized since my peer's terminal window is smaller than mine.

Focus on what you are working on right now.

Say, one session per project/work-item. Easily switch among the handful windows within current session. Windows in other sessions does not distract you.

• A simplistic setup procedure (the section of setup)
• A minimal set of hotkeys (the basic operations)
• A nice support of mouse even though it is a CLI (how to enable mouse support)

• Automatically create or attach to a session

  function tg {
      local session_name="$1"
  
      if [ -n "$session_name" ]; then
          tmux -2 attach -t "$session_name" || tmux -2 new -s "$session_name"
      else
          tmux -2 attach || tmux -2 new -s 'misc'
      fi
  }
  

• Retrieve content of the clipboard of tmux in Emacs

  (defun lgfang-get-tmux-copied ()
    "Get current tmux buffer"
    (interactive)
    (call-process "tmux" nil t nil "show-buffer"))
  

• A more complicated example can be found here

Last but not least: it is BSD-licensed.

That means it is free to

• Use
• Modify
• Re-distribute
• Or even make profit from it.

Copy a statically-linked "tmux" binary to the server.

Most modern linux/unix variants have package manage system like yum/ports which download and install tmux for you in a single command.

For instance, for fedora/rhel

yum install tmux

Here is how you install tmux from source code in case needed. (NOTE: compile a statically linked, 32-bit binary for portability)

# install libevent if not already
tar xvfz libevent-1.4.14b-stable.tar.gz
cd libevent-1.4.14b-stable
./configure --prefix=$HOME/.local
make && make install
tar xvfz tmux-1.6.tar.gz && cd tmux-1.6/
./configure --enable-static --prefix=$HOME/.local \
    CFLAGS="-I$HOME/.local/include" LDFLAGS="-L$HOME/.local/lib"
make && make install

# echo "LD_LIBRARY_PATH=$HOME/.local/bin:$LD_LIBRARY_PATH" >> ~/.bash_profile
echo "PATH=$HOME/.local/bin:$PATH" >> ~/.bash_profile

For cygwin, refer to here.

• Server instance
• Sessions
• Windows
• Panes
• Handover of key-stokes

Refer to my ~/.tmux.conf at ./tmux.html.

Some examples:

# Emacser can not use default prefix 'C-b' :)
set-option -g prefix F12
bind-key | split-window -h
bind-key _ split-window -v

1. Select previous working window :: F12 l
2. Select the N^th window :: F12 N
3. Select next window (index+1) :: F12 n
4. Select previous window (index-1) :: F12 p
5. To rename a window :: =F12 ,= then input new name

1. Select pane :: F12 <Tab>/<left>/<right>/<up>/<down>
2. Swap two adjacent panes :: F12 {
3. Break current pane to a new window :: F12 !
4. Join pane y in window x to current window :: F12 j then type in x.y
5. Swap with pane y of window x :: F12 m then type in x.y
6. Toggle Synchronize mode, i.e. duplicate input (key-stokes) to all panes in the same window :: F12 Ctrl-s. Sometimes, this is can be handy for testers

bind-key Tab select-pane -t:.+
bind-key BTab select-pane -t:.-
set-option -g display-time 3000
bind-key j command-prompt "join-pane -s '%1'"
bind-key m command-prompt -p "move (swap) current pane with: " "swap-pane -s %1"
bind-key C-s setw synchronize-panes

1. F12 [ or F12 <PageUp> to enter ``copy mode'', and then view, search and copy screen output as described below.
   • Scroll up/down: <PageUp> / <PageDown>, or Emacs(or vi if you configured that way) key bindings, or mouse wheel.
   • Search, just use Emacs key bindings for search (or that of vi based on your configure):
     1. Ctrl-r
     2. Type in string to search
     3. Enter
     4. Press n/N for next/previous match
   • Copy: Emacs/vi key bindings
2. Paste: F12 ]
3. Show "clip board": F12 =
4. Customize if you want

   set-window-option -g mode-keys emacs
   set-option -g history-limit 600000
   

1. New session :: F12 : new-session -s session_name
2. Choose(switch) session :: F12 s
3. Move window among sessions :: F12 : move-window -t session_name

1. Command mode: F12 : source-file .tmux.conf
2. Command line command: tmux source-file .tmux.conf

1. F12 : source-file .tmux.conf
2. "restart" tmux does not make new configure take effect?

   You just "restarted" a session, not the tmux server.

3. What does -g in set-option -g mean?

   Without -g, the option applies to current session only.

When you want screen log of current pane, save it with F12 Ctrl-h

bind-key C-h command-prompt -p "save log to:" "copy-mode; send-keys 'M->' C-e C-space 'M-<' C-a C-w; save-buffer %%"
# # if "set-window-option -g mode-keys vi", use this one:
# bind-key C-h command-prompt -p "save log to:" "copy-mode; send-keys g 'space' G 'enter'; save-buffer %%"

Though I do not recommend this one, here it is:

1. Start logging :: F12 h
2. Stop logging :: F12 H

# for mode-keys emacs
bind-key h pipe-pane "cat >>$HOME/#S-#I-#P.log" \; display-message "Start logging($HOME/#S-#I-#P.log)"
bind-key H pipe-pane \; display-message "Stop logging(#S-#I-#P.log)"

There are sometimes when need to nest tmux sessions. For example: Start a tmux session on local Linux box. Then, from within that tmux session, ssh to a server and run another tmux session.

To send prefix to

1. Outer tmux session :: F12
2. Nested tmux session :: F11
3. tmux session nested twice :: F11 Ctrl-b
4. One more layer :: F11 Ctrl-b Ctrl-b (do you really want a nested nested nested … session?)

bind-key -n F11 send-prefix
bind-key C-b send-prefix

1. Normal (follows the prefix) :: bind-key Tab select-pane -t:.+
2. Repeatable :: bind-key -r Space next-layout
3. Without prefix :: bind-key -n F11 send-prefix

Use cases:

1. Show more in the pane for a little while
2. Maximize, copy (drag mouse) and restore

For latest tmux (version 1.8), already has built-in support. F12 z to toggle.

For older versions, here is a trick :

unbind z
bind-key z run "if [[ $(tmux list-window) =~ MAX ]]; then \
     tmux last-window;\
     tmux swap-pane -s MAX.0; \
     tmux kill-window -t MAX; \
     else tmux new-window -d -n MAX; \
     tmux swap-pane -s MAX.0; \
     tmux select-window -t MAX;fi"

Some can not live without

1. auto-login: the emulators remember hostip/username/password.
2. auto-hotkey: a windows software enable you to define your own hotkeys.

I wrote "to" in expect, which is IMHO more convenient.