Shell Programming and Scripting

df

#!/usr/local/bin/bash
#This defines the disk usage for said partition (i.e. it's checking /'s useage, and stripping out everything but the integer
root=`df -F ext3 -k | grep -vE '^Filesystem|tmpfs|cdrom' | grep /dev/sda3 | awk '{ print $5}' | cut -d'%' -f1`
partition=/
#sets threshold
  if [ $root -ge 90 ]; then
#emails alert
     echo "Running out of space \"$partition ($root%)\" on $(hostname) as on $(date)" |
     mail -s "Alert: Almost out of disk space on $(hostname).  $partition is at $root%" someone@domain.com
  fi