Set tmux pane title to short hostname on ssh connections

set-tmux-title

# Make short hostname only if its not an IP address
__tm_get_hostname(){
    local HOST="$(echo $* | rev | cut -d ' ' -f 1 | rev)"
    if echo $HOST | grep -P "^([0-9]+\.){3}[0-9]+" -q; then
        echo $HOST
    else
        echo $HOST| cut -d . -f 1
    fi
}

__tm_get_current_window(){
    tmux list-windows| awk -F : '/\(active\)$/{print $1}'
}

# Rename window according to __tm_get_hostname and then restore it after the command
__tm_command() {
    if [ "$(ps -p $(ps -p $$ -o ppid=) -o comm=| cut -d : -f 1)" = "tmux" ]; then
        __tm_window=$(__tm_get_current_window)
        # Use current window to change back the setting. If not it will be applied to the active window
        trap "tmux set-window-option -t $__tm_window automatic-rename on 1>/dev/null" RETURN
        tmux rename-window "$(__tm_get_hostname $*)"
    fi
    command "$@"
}

ssh() {
    __tm_command ssh "$@"
}

ec2ssh() {
    __tm_command ec2ssh "$@"
}

I found that my tmux program was named tmux-2.1, not tmux, so I generalized things a bit by using case instead of if:

__tm_command() {
    case "$(ps -p $(ps -p $$ -o ppid=) -o comm=| cut -d : -f 1)" in
        tmux*)
            __tm_window=$(__tm_get_current_window)
            trap "tmux set-window-option -t $__tm_window automatic-rename on 1>/dev/null" RETURN
            tmux rename-window "$(__tm_get_hostname $*)"
            ;;
    esac
    command "$@"
}

Hi Mate, Silly question. Where to put code to make it work? I have ~/.tmux.conf where have set few key bindings.

Hi Mate, Silly question. Where to put code to make it work? I have ~/.tmux.conf where have set few key bindings.

The Code listed are functions. So i would suggest you create an general ~/.functions to put them in and add source ~/.functions to your Shell rcfile like ~/.bashrc or ~/.zshrc.

In the grep command on line 4, I think it's better to remove the ^ char, Because most of the time the ssh command starts with a user name not an IP i.e (ssh ubuntu@192.168.1.1) so this condition will mostly be false.

so
-- if echo $HOST | grep -P "^([0-9]+.){3}[0-9]+" -q; then
++ if echo $HOST | grep -P "([0-9]+.){3}[0-9]+" -q; then
Is better on my opinion.

In the grep command on line 4, I think it's better to remove the ^ char, Because most of the time the ssh command starts with a user name not an IP i.e (ssh ubuntu@192.168.1.1) so this condition will mostly be false.

so -- if echo $HOST | grep -P "^([0-9]+.){3}[0-9]+" -q; then ++ if echo $HOST | grep -P "([0-9]+.){3}[0-9]+" -q; then Is better on my opinion.

It depends if you've setup your ssh_config with automatically switching users for hosts. It's better to cover as many possibilities as you can.