Shell Programming and Scripting

filename=$1
filetimestamp=`ls -lrt $filename| awk '{print $7}'`
current_date=`date +%d`
a=`expr $current_date - $filetimestamp`
if [ $a -le 1 ] ; then
echo "File was last updated on `date`"
else
echo "File was not updated from one day"
fi

filename=$1
filedate=`ls -lrt $filename| awk '{print $7}'`
filetimestamp=`ls -lrt $filename | awk '{print $8}' |awk -F ":" '{print $1 $2}'`
fileyear=`ls -lrt $filename | awk '{print $8}'`
filetime=`ls -lrt $filename | awk '{print $8}'`
filemonth=`ls -lrt $filename | awk '{print $6}'`
current_month=`date +%c | awk '{print $2}'`
current_year=`date +%c | awk '{print $5}'`
current_date=`date +%d`
prev_date=`expr $current_date - 1`
date_diff=`expr $current_date - $filedate`
current_time=`date +%H%M`
time_diff=`expr $current_time - $filetimestamp`
if [[ ${#fileyear} -eq 4 ]] ; then
if [ $fileyear -ne $current_year ]  ; then
echo "File is not of year $current_year"
exit
elif [ $filemonth != $current_month ] ; then
echo "File is of year $current_year but not $current_month month"
exit
fi
elif [ $filemonth != $current_month ] ; then
echo "File is of year $current_year but not $current_month month"
exit
fi
 
if [ $filedate -eq $prev_date ] || [ $filedate -eq $current_date ]; then
if [ $filedate -eq $current_date ]; then
echo "File was last updated on $filedate $filemonth $current_year at $filetime"
elif [ $filedate -eq $prev_date ] ; then
if [ $time_diff -le 0 ] ; then
echo "File was last updated on $filedate $filemonth $current_year at $filetime"
else
echo "File was updated on $filedate $filemonth $fileyear but before 24 hours from now"
fi
fi
else
echo "File was updated before $prev_date $current_month $current_year"
fi