Question

I’m new to linux and I’m learning to script an alarm clock using bash and cron. The script works fine from bash and by double clicking on it, but not from cron; as soon as cron calls the script, the alarm sounds once (one loop, it seems) and then stops without even showing the dialog box (zenity). I’m using Linux Mint 13 Maya XFCE.

Here is my crontab setup

* * * * * /home/x/Documents/MyScripts/Cron/BeepAlarm "Wake Up"

And here is my script

!#/bin/bash

# Initialize Variables
Text=$1
Title="Alarm"
OkLabel="Snooze"
CancelLabel='Shut It Up!'
Icon=/home/x/.icons/actions/48/appointment-new.png # Won't work
SnoozeTimeout=120
AlarmCycles=100
shopt expand_aliases
alias vol='amixer -q -c 0 sset Beep'
vol 25% # Heart friendly
rm -f LoopMode # Just in case =P

# Dialog Box Function
_MsgBox () {
    if zenity --question --title="$Title" \
    --window-icon=$Icon --ok-label="$OkLabel" \
    --cancel-label="$CancelLabel" --text="$Text"
    then
        echo 1 > LoopMode
    else
        echo 2 > LoopMode
        #kill -TERM `jobs -p` # Won't work
    fi
}

# Alarm Loop
while [ $AlarmCycles -gt 0 ]; do
    case `cat LoopMode` in
        "") # Question Box
            echo 0 > LoopMode
            _MsgBox &
            ;;

        1)  # Snooze
            vol 25%
            rm -f LoopMode
            sleep $SnoozeTimeout
            ;;

        2)  # Stop Alarm
            break # But don't sleep again
            ;;

        *)  # Get on my nerves
            beep -r 4 -l 20 -f 2000; sleep 0.5
            beep -r 4 -l 20 -f 4000; sleep 0.5
            AlarmCycles=$((AlarmCycles-1))
            vol 5%+

    esac
done

# Housekeeping~
kill $(($!+2)) # I don't know a better way to kill zenity Dialog
vol 25%   #  =)
rm -f LoopMode

Answer 1

As Rob suggested:

* * * * * env DISPLAY=:0.0 /home/x/Documents/MyScripts/Cron/BeepAlarm "Wake Up"

P.S: Sorry, I didn’t pay attention to the formalities