Shell Script App Dir

#! /bin/sh

if [ "$APPHOME" = "" ] ; then
  # try to locate application home directory

  ## resolve links - $0 may be a link to the app home
  PRG=$0
  progname=`basename $0`

  while [ -h "$PRG" ] ; do
    ls=`ls -ld "$PRG"`
    link=`expr "$ls" : '.*-> \(.*\)$'`
    if expr "$link" : '/.*' > /dev/null; then
        PRG="$link"
    else
        PRG="`dirname $PRG`/$link"
    fi
  done

  export APPHOME=`dirname "$PRG"`/..
  export APPHOME=$(cd $APPHOME >/dev/null; pwd)
fi