Bash basic template for argument parsing and basic exit handling

gettingstarted.bash

#!/bin/bash

##
# the handle_argument function receives all the non-option argument or non-flag argument
##
handle_argument() {
    # the first argumeent without any flag
    echo " Argument is : $1 "   
}

# Send error to STDERR
err() {
  echo "[$(date +'%Y-%m-%dT%H:%M:%S%z')]: $@" >&2
}


while [ "$#" -gt 0 ]; do
  case "$1" in
    -f) format="$2"; shift 2;;
    -l) logfile="$2"; shift 2;;

    --format=*) format="${1#*=}"; shift 1;;
    --logfile=*) logfile="${1#*=}"; shift 1;;
    --format|--logfile) echo "$1 requires an argument" >&2; exit 1;;

    -*) echo "unknown option: $1" >&2; exit 1;;
    *) handle_argument "$1"; shift 1;;
  esac
done

err "I'm done here"
exit 0

#Ref: http://stackoverflow.com/questions/192249/how-do-i-parse-command-line-arguments-in-bash