Shell Programming and Scripting

Hey guys,

Need your help/suggestions

I have a log file which has 5K lines in it, I need to send only 200 lines to an application at a time and delete the 200 lines from log fileafter its been fed to application.

The script should keep on running until all 5K has been processed..

Help????

If the log file might still grow while you are handling it, doing this in a shell script sounds rather dangerous. From Perl or Python or C, you might be able to use some file locking primitives to coordinate with processes which might be writing to the file concurrently.

Having said that, consider this (lack of) proof of concept.

Code:

while true; do
  if head -n 200 file | xargs application; then
    sed 1,200d file >file.tmp
    mv -f file.tmp file
    test -s file || break  # quit loop if file empty
  else
    echo "application failed ($?); not removing first 200 lines -- retrying in a while" >&2
  fi
  sleep 600 # or something like that here, maybe?
done

Hi era,

I am getting this error...

sed: can't read requests1: No such file or directory

Code is like this

while true; do
if head -n 500 requests1 > /app//reqs.txt;cd /f/app/Rp/bin
./sApp;
then
sed 1,500d requests1 > reqs.tmp
mv -f reqs.tmp requests1
test -s requests1 || break
else
echo "error";
fi
sleep 2000
done
rm requests1
else
echo " Please try later!! "
exit 0