Mimic dtach with tmux
dtach is a tiny program that emulates detach feature of screen. You can use it to run, for example WeeChat in background without suspending it. And tmux is an awesome feature-rich alternative to screen. So why one would want to use tmux in place of dtach? Personally I do because it allows to change X window title, thus I can make sure WeeChat is always opened on 8th workspace in my XMonad without any extra hacks.
So let’s summarize what I want from tmux:
- no history
- no hotkeys expect the one to “detach”
- no status line
To achieve that I’m gonna create a config for tmux and a launcher something like this:
#!/bin/sh
# file ~/.local/bin/weechat
tmux start
tmux -f ~/.tmux/weechat.conf new -d -A -s weechat weechat-curses \; attach
Pretty simple enough, now all we need is a config for tmux:
# Unbind default prefix, so that there will be no hotkeys available and bind
# hotkeys we are interested in:
unbind C-b
bind-key -n C-\ detach
bind-key -n C-F10 kill-session
# Disable (hide) status line completely
set-option -g status off
# Force tmux to resize a window based on the smallest client actually
# viewing it, not on the smallest one attached to the entire session.
set-window-option -g aggressive-resize on
# 256 Colours
set-option -g default-terminal "screen-256color"
# Set history limit
set-option -g history-limit 0
# Window titling for X
set-option -g set-titles on
set-option -g set-titles-string '#W'
And that’s all. To simplify this process I’ve released a Ruby gem dmux. Alternatively you can (if you by some reason aware of Ruby) use initial Shell script of mine:
#!/bin/sh
set -e
APP=$(echo $* | sed -e "s/^ *| *$//g")
SID=$(echo "$APP" | md5sum | cut -f1 -d" ")
RUN="tmux -L dmux"
CFG="$HOME/.dmux.conf"
if [ -z "$APP" ]; then
echo "USAGE: dmux <command>" >&2
exit 1
fi
test -e "$CFG" || cat > "$CFG" <<CONFIG
# Unbind default prefix, so that there will be no hotkeys available and bind
# hotkeys we are interested in:
unbind C-b
bind-key -n C-\ detach
bind-key -n C-F10 kill-session
# Disable (hide) status line completely
set-option -g status off
# Force tmux to resize a window based on the smallest client actually
# viewing it, not on the smallest one attached to the entire session.
set-window-option -g aggressive-resize on
# 256 Colours
set-option -g default-terminal "screen-256color"
# Set history limit
set-option -g history-limit 0
# Window titling for X
set-option -g set-titles on
set-option -g set-titles-string '#W'
CONFIG
session_exists () {
$RUN has -t "$SID" 2>/dev/null
}
create_session () {
$RUN new -d -A -s "$SID" "$APP" \; source "$CFG" \; attach
}
attach_session () {
$RUN attach -t "$SID"
}
session_exists && attach_session || create_session
Just save it as dmux somewhere within your $PATH environment variable and
don’t forget to chmod +x it.