Calculate sum of the file size

ls -l access_log.2008-12-20*|gawk ‘{a+=$5;} END {print a;}’

Edit special lines using regular expression

awk ‘/aaa/ ‘ filename

Change file names using sed

##Example: from access_log.2008-12-20.01.gz.1  to access_log.2008-12-20.01.1.gz

for file in `ls access_log.2008-12-20.*`

do

newname=`echo $file|sed ‘s/\(access_log.2008-12-20.[0-9][0-9]\).gz.\([0-9]*\)/\1.\2.gz/’`

size=`ls -l $file|awk ‘{print $5}’`

if [ $size -gt 100 ];then

  echo “$file-> $newname”

fi

mv -v $file $newname

done