Hello,

I want to add a line to the user crontab automatically without interaction. That means, I don't want to use crontab -e -u <user>. I'm trying to user the "crontab -l |crontab -" but I don't know how to put the news lines of cronjobs.

Any help?

I use sed to edit my crontab. In the example below, I have a bash function that takes args in the format of <day> hour:minute and replaces the corresponding entry in the crontab.
function setAlarm
CRONFILE=~/cronjobs/crontab.out;
crontab -l >$CRONFILE;
DAY=$1;
HOUR=`echo $2 | awk -F: '{print $1}';`;
MINUTE=`echo $2 | awk -F: '{print $2}';`;
if [ -z "$DAY" ] || [ -z "$HOUR" ] || [ -z "$MINUTE" ]; then
echo "Usage: setAlarm {day} {hour:minute}";
return;
fi;
sed -i.bak -e "/.*${DAY}.*morningPlaylist/s/[0-9][0-9][ \t]*[0-9][0-9]/${MINUTE} ${HOUR}/" $CRONFILE;
crontab $CRONFILE;
crontab -l
}