Set OS X 10.10.x Time Zone using a script and Casper parameter 4

SetTimeZone.sh

#!/bin/sh
# NAME
#	setTimeZone.sh -- Set the time zone
#
# SYNOPSIS
#	sudo setTimeZone.sh
#	sudo setTimeZone.sh <mountPoint> <computerName> <currentUsername> <timeZone>
#
# 	If the $timeZone parameter is specified (parameter 4), this is the time zone that will be set.
#
# 	If no parameter is specified for parameter 4, the hardcoded value in the script will be used.
#
# DESCRIPTION
#	This script sets the system time zone as reflected in the Date & Time preference pane with the
#	System Preferences application.  It has been designed to work on Mac OS X 10.3 and higher.
# HISTORY
#
#	Version: 1.0
#
#	- Created by Nick Amundsen on August 5th, 2008
#	
#	Version: 2.0 
#
#	- Updated by Brock Walters October 28 2014
#
# Version: 3.0
#
# - Updated by Dan DeRusha 2015-28-10
####################################################################################################
#
# DEFINE VARIABLES & READ IN PARAMETERS
#
####################################################################################################

# A HARDCODED VALUE FOR "timeZone" CAN BE SET BELOW.
# A list of accepted time zone values can be generated using the following command in Terminal:
#
#		sudo systemsetup -listtimezones
#
# Delete the double quotes and replace with the desired time zone name, e.g. timeZone=Pacific/Honolulu
# If this script is to be deployed via policy using the JSS leave the next line as is.
# timeZone=""

set -euo pipefail 

# "e" and "o pipefail" let the script exit immediately on errors, "u" exits on undefined variables
# IFS=$'\n\t' # remove "Space" as a field delimiter, helps prevent string splitting.

startTime=$(date "+%Y-%m-%d_%H:%M:%S")
scriptName=$(basename -- "$0") # $0 is the full path to the script. basename removes the path. dirname would return only the path
logDate=$(date "+%Y-%m-%d")
logDir=$(echo "/var/log/$scriptName" | cut -d . -f 1) 
logName="$(echo "$scriptName" | cut -d . -f 1).$logDate.log"
logPath="$logDir/$logName"
OS=$(/usr/bin/defaults read /System/Library/CoreServices/SystemVersion ProductVersion | awk '{print substr($1,1)}')
maj=$(/usr/bin/defaults read /System/Library/CoreServices/SystemVersion ProductVersion | awk '{print substr($1,1,2)}')
ref=$(/usr/bin/defaults read /System/Library/CoreServices/SystemVersion ProductVersion | awk '{print substr($1,4,2)}' | tr -dc '0-9')
timeZone="$4"


# CHECK TO SEE IF A VALUE WAS PASSED IN PARAMETER 4 AND, IF SO, ASSIGN TO "timeZone"

if [ "$4" != "" ] && [ "$timeZone" == "" ]; then
    timeZone=$4
fi

####################################################################################################
# 
# SCRIPT CONTENTS - DO NOT MODIFY BELOW THIS LINE
#
####################################################################################################

touchPath() {
    argT=${1:-}
    if [ -z "$argT" ]; then
        echo "no argument provided to touchPath";
        exit 1;
    fi

    for path in "$@"; do
        if [ ! -d "$(dirname -- "$path")" ]; then
        mkdir -p -- "$(dirname -- "$path")"
        fi
        touch -m -- "$path"
    done
}

# EchoLog writes an argument or piped data to a syslog-style line in stdout and a logfile

EchoLog(){
    logTime=$(date "+%Y-%m-%d_%H:%M:%S") # set date and time here to update on each write
    export BASHPID=$(sh -c 'echo $PPID')
    printLogLine(){
        printf "\n %s \n" "$logTime $(hostname -s) $scriptName s[$$]f[$BASHPID] -- $logMessage" 2>&1 | tee -a "$logPath"
        logger -t "$scriptName s[$$]f[$BASHPID]L" -- "$logMessage" # also write to syslog
    }
    argE=${1:-}
    if [ -n "$argE" ]
        then
            logMessage="$argE"
            printLogLine
        else
            while read -r logMessage; do printLogLine; done
    fi
}
touchPath "$logPath" # check/create log path, touch logfile
EchoLog "##### STARTING $scriptName - $startTime #####"
if [ $maj -gt 10 ]; then
  echo
  EchoLog "Check OS string format & OS X systemsetup utility for script compatibility with OS X versions higher than 10.x.x"
  echo
  exit
fi

if [ "$timeZone" != "" ]; then
	if [ $ref -lt 5 ]; then
		echo
		EchoLog "Setting $timeZone for OS X $OS..."
		echo
		systemsetup -settimezone "$timeZone"
		echo
		/usr/bin/killall SystemUIServer
		EchoLog "Refreshing the clock in the Menu Bar..."
		echo
	else
		echo
		EchoLog "Setting $timeZone for OS X $OS..."
		echo
		systemsetup -settimezone "$timeZone"
		echo
		/usr/bin/killall SystemUIServer
		EchoLog "Refreshing the clock in the Menu Bar..."
		echo	
	fi
else
   echo
   EchoLog "Error: The timeZone variable is not populated. Please specify a valid time zone. A list "
   EchoLog "of accepted time zone values can be generated using the following command in Terminal: "
   echo
   EchoLog "     sudo systemsetup -listtimezones"
   echo
   exit
fi