What's it all about, Alfie?

One of the things I wanted to get done this afternoon was to clean up the bash script I have that runs every night out of cron to clean up (delete) the data files that I can't afford to keep. These are the data files for me feed recorders, and I can afford to keep a few days, but not a lot. The old code I had was really pretty lame - and it scanned the directory looking for subdirectories and looking for the highest sorted name, and picking that one as the "latest".

I did this several times, each pass getting the next one, and the next one, and in the end, I had a list of directories to "keep". Very sloppy. Here's what I came up with this afternoon after just a little bit of fiddling:

  i=0
  for d in `ls | sort -r`
  do
    # skip anything that's not a directory
    if [ ! -d ${d} ]; then
      continue
    fi
    # track count of dirs to keep - and keep 4
    i=$(($i + 1))
    if [ $i -le 4 ]; then
      continue
    fi
    # whatever is left - delete… it's too old
    echo -n '.'
    rm -rf ${d}
  done

The beauty of this script is that I can easily change the number of days to keep - just change the '4' to a '5', and we have a whole (business) week. Very nice. Also, it's a lot more compact than the original approach.

This entry was posted on Thursday, January 12th, 2012 at 4:16 pm and is filed under Coding, Cube Life. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.