Something

#!/bin/sh
X=`pgrep -c irexec`
if [ ${X} -gt 1 ] || [ ${X} -eq 0 ]; then
        echo "to many or to few irexec found"
        sudo /usr/bin/killall irexec
        irexec &
fi

if ! pgrep mythfrontend ; then
        echo "frontend not running, starting!" >> /var/log/mythtv/frontend.log
        DISPLAY=":0.0" xset s off
        DISPLAY=":0.0" xset -dpms
        DISPLAY=":0.0" mythfrontend -l /var/log/mythtv/frontend.log -v important,playback &
fi