LinuxQuestions.org - [SOLVED] Empty email when the script run as a cron job

Hello,

I've got a script that check for hard-drive temperature and send an email if one of the hard-driver is too hot. This script run perfectly when running "by hand", but once added to the crontab, it mostly works, but the emails sent are empty while its subject is OK!!! I know that cron environment is not a full user environment but I can't figure where the problem stand (what environment variable I'm missing).

Here's my script:

Code:

#!/bin/sh



check_one () {

    hdd="$1"

    if [ -z "$2" ]; then

        temp_max=55

    else

        temp_max=$2

    fi

    temp=`hddtemp "$hdd" | awk -F":" '{print $3}' \

                        | sed 's/^ *//' | sed 's/[^0-9]*$//'`

    if [ "$temp" -gt "$temp_max" ]; then

        echo "$hdd reached $temp °C > $temp_max °C\n"

    fi

}



if [ -z "$1" ]; then

    TEMP_MAX=55

else

    TEMP_MAX=$1

fi

if [ ! -z "$2" ]; then

    EMAIL=$2

fi

WARNING="`check_one /dev/sda $TEMP_MAX`"

WARNING="$WARNING`check_one /dev/sdb $TEMP_MAX`"

WARNING="$WARNING`check_one /dev/sdc $TEMP_MAX`"

if [ ! -z "$WARNING" ]; then

    if [ -z "$EMAIL" ]; then

        echo -e "$WARNING"

    else

        echo -e $WARNING | mailx -s 'Harddrive temperature' $EMAIL

        #TMPFILE=`mktemp`

        #echo -e $WARNING > "$TMPFILE"

        #mailx -s 'Harddrive temperature' $EMAIL < "$TMPFILE"

        #rm "$TMPFILE"

    fi

fi

My "/etc/ssmtp/ssmtp.conf" should be OK since the emails are received, but maybe something's missing there due to cron?

Code:

root=jf.argentino@email.fr

AuthUser=jf.argentino@email.fr

AuthPass=passwd

UsesTLS=YES

UsesSTARTTLS=YES

mailhub=ssl0.ovh.net:465

"/etc/ssmtp/revaliases" is empty

and by crontab:

Code:

0-59/5 * * * * /usr/bin/hddtemp.sh 55 jf.argentino@email.fr

If I'm storing the message to send into a file (commented in the script above), the email is still empty...

If I do not erase the temporary file, the email is still empty, but the file contents the message I want to send.

If the message content is not in a variable, I'm receiving it...

So it looks like my problem is relative to both variable and redirection handling by cron, but I can't fix this.

Does anybody have an idea?

My system is a Scientific Linux 6.3 up to date