tmx

#!/bin/bash

#
# Tmux launcher
#
# See:
#     http://github.com/brandur/tmux-extra
#
# Modified version of a script orginally found at:
#     http://forums.gentoo.org/viewtopic-t-836006-start-0.html
#

#If we're running inside iTerm, integrate with its tmux support
if [ x"$TERM_PROGRAM" = x"iTerm.app" ]; then
  TMUX_CMD="tmux -CC"
else
  TMUX_CMD="tmux"
fi

# Works because bash automatically trims by assigning to variables and by 
# passing arguments
trim() { echo $1; }

#TMUX_SUPPORTS_MINUS_F=$(tmux list-sessions -F '#{session_name}' > /dev/null 2>&1 && echo 0 || echo 1)
#...but that hangs on Linux due to epoll problems -- see
# https://sourceforge.net/tracker/?func=detail&atid=973262&aid=3489496&group_id=200378
TMUX_SUPPORTS_MINUS_F=1  #disable -F support

tmux-list-sessions() {
    if [[ "$TMUX_SUPPORTS_MINUS_F" == 0 ]] ; then
        tmux list-sessions -F '#{session_name}'
    else
        tmux list-sessions | cut -d: -f 1
    fi
}

tmux-list-old-sessions() {
    if [[ "$TMUX_SUPPORTS_MINUS_F" == 0 ]] ; then
        tmux list-sessions -F '#{?session_attached,,#{?session_grouped,,#{session_name}}}'
    else
        tmux list-sessions 2>/dev/null | grep -v '(group [[:digit:]]\+)' | grep -v '(attached)' | cut -d: -f 1
    fi
}

if [[ -z "$1" ]]; then
    echo "Specify session name as the first argument"
    exit
fi

# Only because I often issue `ls` to this script by accident
if [[ "$1" == "ls" ]]; then
    tmux ls
    exit
fi

base_session="$1"
# This actually works without the trim() on all systems except OSX
tmux_nb=$(trim `tmux-list-sessions | grep -c "^$base_session$"`)
if [[ "$tmux_nb" == "0" ]]; then
    echo "Launching tmux base session $base_session ..."

    # we separate 'new-session' and 'attach' to allow .tmux.conf
    # commands to create the new session first with the right name
    # (which is, after all, a simple convention so easily shared),
    # which will (perversely) then cause this new-session command to
    # exit with an error.  Despite this error, a new session with
    # exactly that name has been created.  Then we can happily attach
    # to it.  If .tmux.conf has no new-session command in it, our
    # explicit 'new-session' creates it, and we attach happily, again,
    # to it.
    $TMUX_CMD new-session -d -s $base_session
    $TMUX_CMD attach         -t $base_session

else
    # Make sure we are not already in a tmux session
    if [[ -z "$TMUX" ]]; then
        if [[ -z "$TMUX_PRESERVE_UNATTACHED_SESSIONS" ]] ; then
            # Kill defunct sessions first
            for old_session_id in `tmux-list-old-sessions` ; do
                tmux kill-session -t $old_session_id
            done
        fi

        echo "Launching copy of base session $base_session ..."

        # Find a session prefix number that hasn't already been used
        num_prefix=1
        while [[ $(trim `tmux-list-sessions | grep "^$num_prefix,$base_session" | wc -l`) -gt 0 ]];
        do
            num_prefix=`expr $num_prefix + 1`
        done
        session_id="$num_prefix,$base_session"
        # Create a new session (without attaching it) and link to base session
        # to share windows
        tmux new-session -d -t $base_session -s $session_id
        # Attach to the new session
        $TMUX_CMD attach-session -t $session_id
        # When we detach from it, kill the session
        $TMUX_CMD kill-session -t $session_id
    fi
fi