shell script template, fairly comprehensive program

shelltemplate.sh

#!/bin/bash
#*******************************************************#
# Shell script template                                 #
#                                                       #
# Arunachalesha                                         #
# $Id$  #
#*******************************************************#
# if running as a cronjob prepend /opt/local/bin:/opt/local/sbin
# export PATH="/opt/local/bin:/opt/local/sbin:$PATH:/Users/rahul/bin"
# also cd in the folder you want.
# cd /Users/rahul/bin
#### --- cleanup code use at start ---- ####
# TMP_FILE=${TMPDIR:-/tmp}/prog.$$
# trap "rm -f $TMP_FILE.?; exit 1" 0 1 2 3 13 15
# at end of prog
#rm -f $TMP_FILE.?
#trap 0
#exit 0
PROG_SH=$(basename "$0")
export PROG_SH


#ext=${1:-"default value"}
#today=$(date +"%Y-%m-%d-%H%M")

oneline_usage="$PROG_SH [-fhpantvV] [-d todo_config] action [task_number] [task_description]"
usage()
{   
    sed -e 's/^    //' <<EndUsage
    Usage: $oneline_usage
    Try '$PROG_SH -h' for more information.
EndUsage
    exit 1
}
help()
{
    sed -e 's/^    //' <<EndHelp
      Usage: $oneline_usage

      Actions:
        add "THING I NEED TO DO +project @context"
        a "THING I NEED TO DO +project @context"
          Adds THING I NEED TO DO to your todo.txt file on its own line.
          Project and context notation optional.
          Quotes optional.

        addto DEST "TEXT TO ADD"
      See "help" for more details.
EndHelp
    exit 0
}
die()
{
    echo "$*"
    exit 1
}
cleanup()
{
    [ -f "$TMP_FILE" ] && rm "$TMP_FILE"
    exit 0
}

vflag=0
out=
file=
Dflag=
while getopts hvVf:o:D: flag
do
    case "$flag" in
    (h) help; exit 0;;
    (V) echo "$arg0: version $Revision$ ($Date$)"; exit 0;;
    (v) vflag=1;;
    (f) file="$OPTARG";;
    (o) out="$OPTARG";;
    (D) Dflag="$Dflag $OPTARG";;
    (*) usage;;
    esac
done
shift $(($OPTIND - 1))

[ $# -eq 0 ] && {
exit 0;
}


action=$( printf "%s\n" "$1" | tr 'A-Z' 'a-z' )
shift

case $action in
"add" | "a")
    echo "action is $action"
    echo "left is $*"
       cleanup;;
"del" | "rm")
    echo "action is $action"
    echo "left is $*"
       cleanup;;
"move" | "mv")
    echo "action is $action"
    echo "left is $*"
       cleanup;;
"list" | "ls")
    echo "action is $action"
    echo "left is $*"
       cleanup;;
* )
    usage
    ;;
esac