#!/bin/sh
  
  # Output warnings if disks are too full (in percentage
  # terms) or have too little space available.
  
  # This script goes through all the mounted filesystems
  # and checks each to see if the disk is nearly full,
  # reporting only on those disks that warrant more attention.
  
  # Set thresholds
  min_free=4000
  
  max_in_use=55
  
  # Get a list of all file systems.
  filesystems=`df -k | grep -v Use | grep -v none | awk '{ print $6 }'`
  
  for filesystem in $filesystems\; do\; \#\; Cache\; results\; for\; this\; file\; system.\; entry=`df\; -k$filesystem | tail -1`  
  
      # Split out the amount of space free as well as in-use percentage.
      free=`echo $entry\; |\; cut\; -d\text{'}\; \text{'}\; -f4`\; in\_use=`echo$entry | cut -d' ' -f5 | cut -d'%' -f1 `
  
      # Check the file system percent in use.
      if [ $(expr "$in\_use\; >$max_in_use" ) ]
      then
          echo "$filesystem\; has\; only$free KB free at $in\_use\%."\; else\; \#\; Check\; the\; available\; space\; against\; threshold.\; \#\; Only\; make\; this\; check\; if\; the\; in\; use\; is\; OK.\; result=\$(\; echo\; "\; scale=2$/* two decimal places */
              print free < $min\_free"\; |\; bc)\; \#if\; [\; \$(expr\; "$free < $min\_free"\; )\; ]\; if\; [\; \$(expr\; "$result != 0" ) ]
          then
              echo "$filesystem\; has\; only$free KB free."
          fi
      fi
  
  done