#!/bin/bash
    # $Id: //depot/prod/capstan/main/src/plugins/unix/examples/backup/create/pre/disk_space_estimate.sh#5 $
    name="disk space estimation ($(basename $0))"
    description="pre tasks for estimating the space on the target system"
    context=
    timeout="0"
    parameter=()
    EXIT=0
    PRESERVE_DIR="/tmp/preserve/$(date +%Y%m%d%H%M%S)"
    function _exit {
       rc=$1
       echo "Command complete."
       exit $rc
    }
    function usage {
       echo "usage: $(basename $0) { -check | -describe | -execute }"
       _exit 99
    }
    function describe {
       echo "SM_PI_NAME:$name"
       echo "SM_PI_DESCRIPTION:$description"
       echo "SM_PI_CONTEXT:$context"
       echo "SM_PI_TIMEOUT:$timeout"
       IFS=^
       for entry in ${parameter[@]}; do
           echo "SM_PI_PARAMETER:$entry"
       done
       _exit 0
    }
    function check {
       _exit 0
    }
    function execute {
       echo "estimating the space on the target system"
       # Shell script to monitor or watch the disk space
       # It will display alert message, if the (free available) percentage
       # of space is >= 90%
       # ----------------------------------------------------------------------
       # Linux shell script to watch disk space (should work on other UNIX oses )
       # set alert level 90% is default
       ALERT=90
       df -H | grep -vE '^Filesystem|tmpfs|cdrom' | awk '{ print $5 " " $1 }' | while read output;
       do
         #echo $output
         usep=$(echo $output | awk '{ print $1}' | cut -d'%' -f1  )
         partition=$(echo $output | awk '{ print $2 }' )
       if [ $usep -ge $ALERT ]; then
           echo "Running out of space \"$partition ($usep%)\" on $(hostname) as on $(date)" |
       fi
       done
      _exit 0
     }
    function preserve {
        [ $# -ne 2 ] && return 1
        file=$1
        save=$(echo ${2:0:1} | tr [a-z] [A-Z])
        [ "$save" == "Y" ] || return 0
        if [ ! -d "$PRESERVE_DIR" ] ; then
           mkdir -p "$PRESERVE_DIR"
           if [ $? -ne 0 ] ; then
               echo "could not create directory [$PRESERVE_DIR]"
               return 1
           fi
        fi
        if [ -e "$file" ] ; then
            mv "$file" "$PRESERVE_DIR/."
        fi
        return $?
    }
    case $(echo $1 | tr [A-Z] [a-z]) in
        -check)    check
                  ;;
        -execute)  execute
                  ;;
        -describe) describe
                  ;;
     *)         echo "unknown option $1"
              usage
              ;;
     esac