MIN_SIZE=”5000000″
IN_DIR=”/home/kis_pista”
OUT_DIR=”/mnt/dvd/out_dir”
DEVICE=”/dev/dvd1″
DF=””
TMP_NUM=”0″
FREE_SIZE=””
OLDEST_FILE=””
ID=”0″

DeleteData() {
for TMP_FREE_SIZE in `df | grep ${DEVICE} | cat`; do
TMP_NUM=$[$[TMP_NUM]+1]
if [ $[TMP_NUM] -eq 3 ]; then
FREE_SIZE=${TMP_FREE_SIZE}
fi
done

if [ $[FREE_SIZE] -lt $[MIN_SIZE] ]; then
OLDEST_FILE=`ls ${OUT_DIR} -c -r`
echo „*** Delete oldest file: ${OLDEST_FILE} ***”
rm „${OUT_DIR}/${OLDEST_FILE}”
fi
}

SaveData() {
while [ -e ${OUT_DIR}/backup.${ID}.tar.bz2 ]; do
ID=$[$[ID]+1]
done

echo „*** Save data from ${IN_DIR} to ${OUT_DIR}/backup.${ID}.tar.bz2 ***”
tar -cjf ${OUT_DIR}/backup.${ID}.tar.bz2 ${IN_DIR}
}

DeleteData
SaveData