remove_lxc_pid() {
    # in : list of pid
    # out : list of pid without lxc process
    # if kernel don't have cgroup, return all pids
    if [[ ! -f /proc/self/cgroup ]] ; then
	echo -n $@
	return
    fi
    local CGROUP=$(cat /proc/self/cgroup 2> /dev/null)
    # if self cgroup info is not ended by :/
    # we are inside lxc, return all pids
    if [[ ! ${CGROUP:(-2)} = ':/' ]]  ; then
	echo -n $@
	return
    fi
    local PID=''
    local NOLXC=''
    # Loop on all pids
    for PID in $@
    do
	# if PID don't existe : go next
	# [[ -d /proc/${PID} ]] || continue
	# CGROUP=$(cat /proc/${PID}/cgroup)
	# Get info from cgroup
	CGROUP=$(cat /proc/${PID}/cgroup 2> /dev/null)
	# if cgroup info is ended by :/ is not a lxc process
	# cgroup lxc process is ended by lxc name
	[[ ${CGROUP:(-2)} = ':/' ]] && NOLXC="$PID $NOLXC"
    done
    # Remove ending space
    echo -n ${NOLXC/% }
}

pidof() {
    echo $(remove_lxc_pid $(/bin/pidof $@))
}