自动清空/var/log1下的messages文件

#vi 1sh && chmod +x 1.sh

LOG_DIR=/var/log1

ROOT_UID=0

LINES=50

ERROR_CANTCD=112

ERROR_NOTROOT=765

if [ "$UID" -ne "$ROOT_UID" ]

then

echo "only root can run this script"

exit $ERROR_NOTROOT

if [ -n "$1" ]

then

lines=$1

else

lines=$LINES

fi

cd $LOG_DIR

if [ `pwd` != $LOG_DIR ]

then

echo "can not change to $LOG_DIR"

exit $ERROR_CANTCD

tail -$lines messages > mesg.tmp

mv mesg.tmp

echo "logs cleaned"

exit 0