#!/bin/bash
if [ "x$1" != "x" ]
then
  pgrep -l -u "$USER" -f "$1" | egrep -v "/bin/bash|/bin/sh" | grep -vq "$$"
  if [ $? == "0" ]
  then
    WID=`xdotool search --class $1 | head -1`
    wmctrl -i -a $WID
    if [ "x$2" != "x" ]
    then
      eval "$2"
    fi
  else
    if [ "x$3" == "x" ]
    then
      /usr/bin/$1
    else
      eval "$3"
    fi
  fi
else
  echo "Usage: one-instance program-name [extra action]"
fi