Creates Bootable USB for Mac OS Lion to Monterey (Excluding Mavericks)

Install_USB_Maker.sh

#!/usr/bin/env bash

# Install_USB_Maker.sh
# Copyright (c) 2020 - 2024 Dayo Akanji
# - dakanji@users.sourceforge.net
# Portions Copyright (c) Jeff Geerling
# - https://github.com/geerlingguy/macos-virtualbox-vm/blob/master/LICENSE
#
# MIT License

# Derived from:
#    * https://apple.stackexchange.com/a/389830
#    * https://github.com/geerlingguy/macos-virtualbox-vm/blob/master/prepare-iso.sh
#
# 1. Download Lion to Monterey (Excluding Mavericks)
#    * From    : https://support.apple.com/HT211683 (Lion to Sierra or Links to App Store)
#    *         : https://github.com/corpnewt/gibMacOS (High Sierra to Monterey)
# 2. Use Disk Utility to format a USB stick partition:
#    * Name    : USB_Maker
#    * Size    : Easiest to assume 16 GB but see details below:
#    *         : 08 GB (Min) For Lion to Sierra (if via Install DMG)
#    *         : 16 GB (Min) For Yosemite to Sierra (if via Installer App)
#    *         : 16 GB (Min) For High Sierra to Monterey (Always Installer App)
#    * Format  : Mac OS Extended Journaled (HFS+)
# 3. Make the downloaded "Install" package available to this script:
#    * For Lion to Sierra:
#    *     Mount the downloaded "Install DMG" file
#    *     Close the Finder window for the DMG if displayed
#    * For High Sierra to Monterey:
#    *     Place the install app in the 'Applications' folder
#    *     This can be done manually or by running the downloaded package
#    *     Placing manually in the folder containing this script also works
#    *     Installer Apps in the folder containing this script take precedence
#    * For Yosemite to Sierra (Alternative Option):
#    *     Place the install app in the 'Applications' folder
#    *     This can be done manually or by running the downloaded package
#    *     Placing manually in the folder containing this script also works
#    *     Installer Apps in the folder containing this script take precedence
# 4. Make this script executable and run it in Terminal:
#    * Unzip the package to show the script file in Finder
#    * Type  "chmod +x" without quotes, add a space, then drag the script file from Finder unto Terminal and press "Enter"
#    * Type  "sh" without quotes, add a space, then drag the script file from Finder unto Terminal again and press "Enter"
# 5. Install Mac OS with the USB Installer once done
#    * Name    : Install_{{MAC_OS_NAME}}

## CUSTOM COLOURS ##
msg_status() {
	printf "\033[0;35m$1\033[0m\n"
}
msg_info() {
	printf "\033[0;33m$1\033[0m\n"
}
msg_error() {
	printf "\033[0;31m$1\033[0m\n"
}

chiil_msg() {
    msg_info 'NB: Patience ... This takes a while to complete'
	msg_info '    Type password and press "Enter" if prompted'
	msg_info '    Your password is not displayed while typing'
}

# createISO by Jeff Geerling as modified by Dayo Akanji
# This function creates the ISO image.
# Inputs:  $1 = The name of the installer - located in Applications folder or local folder/PATH.
function createISO() {
	local installerAppName
	local isoName
	local error
	local SparseImageFile
	local InstallAppVol
	local InstallAppBaseSystem

    if [ -e "${SCRIPT_DIR}/${1}" ] ; then
        installerAppName="${SCRIPT_DIR}/${1}"
    elif [ -e "/Applications/${1}" ] ; then
        installerAppName="/Applications/${1}"
    else
        echo; echo
        msg_info 'ERROR!!'
        msg_error "Could Not Find Installer App"
        runExit 'Error' ;
    fi

    # Remove Spaces in 'INSTALL_NAME' and use as ISO name
    isoName=$( echo "${INSTALL_NAME}" | sed 's/ //g' )
    error=0
	SparseImageFile="${INSTALL_TEMP}/${isoName}.sparseimage"
	InstallAppVol='/Volumes/install_app'
	InstallAppBaseSystem="${installerAppName}/Contents/SharedSupport/BaseSystem"

    sudo -v
    msg_info "Using Installer App:- '${installerAppName}'"
	msg_status "STEP 01 of 13: Create a Blank 16GB Single Partition Apple Partition Map ISO Image"
	# Create INSTALL_TEMP folder
	mkdir -p "${INSTALL_TEMP}"
	# Just in case - delete any previous sparseimage
	[ -e "${SparseImageFile}" ] && rm -f "${SparseImageFile}"
	# increased size to 16G - 8G is too small for Catalina
	hdiutil create -o "${INSTALL_TEMP}/${isoName}" -size 16g -layout SPUD -fs HFS+J -type SPARSE

	sudo -v; echo
	msg_status "STEP 02 of 13: Mount Installer Image"
	if [ "${isoName}" == "Monterey" ] || [ "${isoName}" == "BigSur" ] ; then
		hdiutil attach "${SparseImageFile}" -noverify -nobrowse -mountpoint  "${InstallAppVol}"
	elif [ -e "${installerAppName}" ] ; then
		hdiutil attach "${installerAppName}/Contents/SharedSupport/InstallESD.dmg" -noverify -nobrowse -mountpoint  "${InstallAppVol}"
		error=$?
	else
		error=999
	fi

	if [ ${error} -ne 0 ] ; then
		echo; echo
		msg_info 'ERROR!!'
		msg_error "Failed to mount the InstallESD.dmg from the installer at ${installerAppName}"
		msg_error "Exiting on 'Error Code: ${error}'"
		runExit 'Error' ;
	fi

	sudo -v; echo
	msg_status "STEP 03 of 13: Mount Sparse Bundle for Package Addition"
	if [ "${isoName}" == "Monterey" ] || [ "${isoName}" == "BigSur" ] ; then
		echo "N/A ... Skipped for ${INSTALL_NAME}"
	else
		hdiutil attach "${SparseImageFile}" -noverify -nobrowse -mountpoint '/Volumes/install_build'
	fi

	sudo -v; echo
	msg_status "STEP 04 of 13: Restore Base System into '${isoName}' ISO Image"
	if [ "${isoName}" == "Monterey" ] || [ "${isoName}" == "BigSur" ] ; then
		echo "N/A ... Skipped for ${INSTALL_NAME}"
	elif [ "${isoName}" == "Catalina" ] || [ "${isoName}" == "Mojave" ] || [ "${isoName}" == "HighSierra" ] ; then
		# Note by Jeff Geerling
		#following asr command returns an error and prints:
		#"Personalization succeeded"
		#"asr: Couldn't personalize volume /Volumes/macOS Base System - Operation not permitted"
		#I disabled SIP and the error still occurs.
		#This was reported in Issue #73 for Mojave
		#Added '|| true' for now to prevent the script from exiting as the steps that follow still seem to work fine for Catalina
		sudo asr restore -source  "${InstallAppBaseSystem}.dmg" -target '/Volumes/install_build' -noprompt -noverify -erase  || true
	else
		sudo asr restore -source  "${InstallAppVol}/BaseSystem.dmg" -target '/Volumes/install_build' -noprompt -noverify -erase
	fi

	sudo -v; echo
	msg_status "STEP 05 of 13: Remove Package Link and Replace with Actual Files"
    chiil_msg ;
	if [ "${isoName}" == "Monterey" ] || [ "${isoName}" == "BigSur" ] ; then
		echo "N/A ... Skipped for ${INSTALL_NAME}"
	elif [ "${isoName}" == "Catalina" ] || [ "${isoName}" == "Mojave" ] || [ "${isoName}" == "HighSierra" ] ; then
		ditto -V  "${InstallAppVol}/Packages" "${VOL_BASE_DIR}/System/Installation/"
	else
		rm -v "${VOL_BASE_DIR}/System/Installation/Packages"
		cp -rpv "${InstallAppVol}/Packages" "${VOL_BASE_DIR}/System/Installation/"
	fi

	sudo -v; echo
	msg_status "STEP 06 of 13: Copy '${INSTALL_TARGET}' Dependencies"
    msg_info 'NB: Type password and press "Enter" if prompted'
    msg_info '    Your password is not displayed while typing'
    sudo -v
	if [ "${isoName}" == "Monterey" ] || [ "${isoName}" == "BigSur" ] ; then
        CurrentMacOS=$(sw_vers -productVersion)
        if [[ "${CurrentMacOS}" == *"10.12."* ]] ; then
            PostHiSierra="False"
        elif [[ "${CurrentMacOS}" == *"10.11."* ]] ; then
            PostHiSierra="False"
        elif [[ "${CurrentMacOS}" == *"10.10."* ]] ; then
            PostHiSierra="False"
        elif [[ "${CurrentMacOS}" == *"10.9."* ]] ; then
            PostHiSierra="False"
        elif [[ "${CurrentMacOS}" == *"10.8."* ]] ; then
            PostHiSierra="False"
        elif [[ "${CurrentMacOS}" == *"10.7."* ]] ; then
            PostHiSierra="False"
        elif [[ "${CurrentMacOS}" == *"10.6."* ]] ; then
            PostHiSierra="False"
        elif [[ "${CurrentMacOS}" == *"10.5."* ]] ; then
            PostHiSierra="False"
        elif [[ "${CurrentMacOS}" == *"10.4."* ]] ; then
            PostHiSierra="False"
        else
            PostHiSierra="True"
        fi

        if [ "${PostHiSierra}" == "True" ] ; then
            sudo "${installerAppName}/Contents/Resources/createinstallmedia" --volume "${InstallAppVol}" --nointeraction
        else
            sudo "${installerAppName}/Contents/Resources/createinstallmedia" --volume "${InstallAppVol}" --applicationpath "${installerAppName}"
        fi
	elif [ "${isoName}" == "Catalina" ] || [ "${isoName}" == "Mojave" ] || [ "${isoName}" == "HighSierra" ] ; then
		ditto -V  "${InstallAppBaseSystem}.chunklist" "${VOL_BASE_SYS}.chunklist"
		ditto -V  "${InstallAppBaseSystem}.dmg" "${VOL_BASE_SYS}.dmg"
	else
		cp -rpv  "${InstallAppVol}/BaseSystem.chunklist" "${VOL_BASE_SYS}.chunklist"
		cp -rpv  "${InstallAppVol}/BaseSystem.dmg" "${VOL_BASE_SYS}.dmg"
	fi

	sudo -v; echo
	msg_status "STEP 07 of 13: Unmount Installer Image"
	if [ "${isoName}" == "Monterey" ] || [ "${isoName}" == "BigSur" ] ; then
		hdiutil detach "/Volumes/Install macOS ${INSTALL_NAME}" -force # NOTE: force because "Resource busy"
	else
		hdiutil detach "${InstallAppVol}"
	fi

	sudo -v; echo
	msg_status 'STEP 08 of 13: Unmount Sparse Bundle'
	if [ "${isoName}" == "Monterey" ] || [ "${isoName}" == "BigSur" ] ; then
		echo "N/A ... Skipped for ${INSTALL_NAME}"
	else
		hdiutil detach "${VOL_BASE_DIR}/"
	fi

	sudo -v; echo
	msg_status "STEP 09 of 13: Resize '${isoName}' Sparse Bundle to Remove Free Space"
	hdiutil resize -size `hdiutil resize -limits "${SparseImageFile}" | tail -n 1 | awk '{ print $1 }'`b "${SparseImageFile}"
    echo "Resized '${isoName}' Sparse Bundle"

    sudo -v; echo
	msg_status "STEP 10 of 13: Convert '${isoName}' Sparse Bundle to ISO/CD Master"
    chiil_msg ;
	hdiutil convert "${SparseImageFile}" -format UDTO -o "${INSTALL_TEMP}/${isoName}"
	sudo rm -vf "${SparseImageFile}"

	sudo -v; echo
	msg_status 'STEP 11 of 13: Convert ISO/CD Master to Regular Image'
    sudo rm -rf "${HOME}/Desktop/${INSTALL_TARGET}.iso" || true
    sudo mv -vf "${INSTALL_TEMP}/${isoName}.cdr" "${INSTALL_TEMP}/${INSTALL_TARGET}.iso"

    sudo -v; echo
	msg_status "STEP 12 of 13: Rename '${INSTALL_ID}'..."
    sudo diskutil rename "${INSTALL_ID}" "${INSTALL_TARGET}"

    sudo -v; echo
	msg_status "STEP 13 of 13: Finishing"
    chiil_msg ;
    sudo mv -vf "${INSTALL_TEMP}/${INSTALL_TARGET}.iso" "${HOME}/Desktop/${INSTALL_TARGET}.iso"
	sudo rm -rf "${INSTALL_TEMP}" || true
    echo; echo
	msg_info 'Complete'
    echo; echo

    msg_status 'NB: Use a tool such as BalenaEtcher to create bootable USB'
    msg_status "    From: '${HOME}/Desktop/${INSTALL_TARGET}.iso'"
	runExit ;
}

# installerExists by Jeff Geerling
# Returns 0 if the installer was found locally or in '/Applications'.  1 if not.
function installerExists() {
	local installerAppName
	local result

	installerAppName="${1}"
	result=1
    if [ -e "${SCRIPT_DIR}/${installerAppName}" ] ; then
		result=0
	elif [ -e "/Applications/${installerAppName}" ] ; then
		result=0
	fi
	return ${result}
}

## EXIT HANDLER ##
runExit() {
	flag=${1:-Norm}
	if [ "${flag}" != 'Norm' ] ; then
        rm -rf "${INSTALL_TEMP}"
    	echo; echo
    	msg_info "Runtime Error!!"
    	msg_error "Could Not Create USB Installer"
        echo; echo
    	exit 1
    else
        echo; echo
		msg_info 'All Done!'
        echo; echo
        msg_info '################################'
    	msg_info ' ##  Create Mac OS Install USB ##'
    	msg_info '  ################################'
        echo; echo
    	exit 0
	fi
}

## ERROR HANDLER ##
runErr() {
    rm -rf "${INSTALL_TEMP}"
	echo; echo
	msg_info "Runtime Error!!"
	msg_error "Could Not Create USB Installer"
	echo; echo
    exit 1
}
trap runErr ERR


##
## Start Procedural Code
##
INSTALL_TARGET='NotSet'
INSTALL_BASIC='Install OS X'
INSTALL_TYPE='NotSet'
INSTALL_NAME='NotSet'
INSTALL_TEMP='/tmp/VersionOSX'
INSTALL_BASE='OS X Base System'
INSTALL_APP='Mac OS Install'
INSTALL_ESD='/Volumes/TMP_ESD'
INSTALL_ID='USB_Maker'
INSTALL_X='InstallMacOSX'
TYPE_OSX="macOS"
TMP_STR='NotSet'
USE_APP='NotSet'
VOL_BASE_SYS='NotSet'
VOL_BASE_DIR='NotSet'

if [ ! -d "/Volumes/${INSTALL_ID}" ] ; then
	err_msg="Connect a correctly sized USB stick labelled as '${INSTALL_ID}' and rerun this script."
	echo; echo
	msg_info 'ERROR!!'
	msg_error "${err_msg}"
	echo; echo
	exit 1
fi

# Resolve TMP_SOURCE until the file is no longer a symlink
TMP_SOURCE=${BASH_SOURCE[0]}
while [ -L "${TMP_SOURCE}" ]; do
	DIR=$( cd -P "$( dirname "${TMP_SOURCE}" )" >/dev/null 2>&1 && pwd )
	TMP_SOURCE=$(readlink "${TMP_SOURCE}")
	# if ${TMP_SOURCE} is relative symlink, resolve relative to symlink file location
	[[ ${TMP_SOURCE} != /* ]] && TMP_SOURCE=${DIR}/${TMP_SOURCE}
done
SCRIPT_DIR=$( cd -P "$( dirname "${TMP_SOURCE}" )" >/dev/null 2>&1 && pwd )

sudo clear
echo; echo
msg_info '  ################################'
msg_info ' ##  Create Mac OS Install USB ##'
msg_info '################################'

echo; echo
msg_info '## STAGE 1 of 4: Confirm Install Target ##'
msg_info '------------------------------------------'
msg_status 'STEP 01 of 02: Get Mac OS Target'
PS3='Enter Corresponding Number for Mac OS Version or Exit: '
options=("Monterey" "Big Sur" "Catalina" "Mojave" "High Sierra" "Sierra" "El Capitan" "Yosemite" "Mavericks" "Mountain Lion" "Lion" "Exit")
select opt in "${options[@]}"
do
	case $opt in
		"Monterey" | "Big Sur" | "Catalina" | "Mojave" | "High Sierra")
			INSTALL_NAME="${opt}"
			USE_APP='True'
        break
        ;;
    	"Sierra")
			INSTALL_X='InstallOS'
			INSTALL_NAME="${opt}"
			USE_APP='Maybe'
			INSTALL_BASIC='Install macOS'
			INSTALL_APP="Install Mac OS ${INSTALL_NAME}.app"
        break
        ;;
    	"El Capitan" | "Yosemite")
			INSTALL_NAME="${opt}"
			USE_APP='Maybe'
			INSTALL_APP="Install Mac OS X ${INSTALL_NAME}.app"
        break
        ;;
		"Mountain Lion")
			INSTALL_NAME="${opt}"
			USE_APP='False'
			INSTALL_BASE='Mac OS X Base System'
			INSTALL_BASIC='Install Mac OS X'
			INSTALL_APP="Install OS X ${INSTALL_NAME}.app"
		break
        ;;
        "Lion")
			INSTALL_NAME="${opt}"
			USE_APP='False'
			INSTALL_BASE='Mac OS X Base System'
			INSTALL_BASIC='Install Mac OS X'
			INSTALL_APP="Install Mac OS X ${INSTALL_NAME}.app"
		break
        ;;
		"Mavericks")
			TMP_STR='Exit'
			INSTALL_NAME="${opt}"
		break
        ;;
        "Exit")
			TMP_STR='Exit'
        break
        ;;
        *)
			echo; echo
			msg_info 'ERROR!!'
            msg_error "Invalid Selection:- '${REPLY}'"
			echo; echo
			exit 1
        ;;
    esac
done

sudo -v; echo
msg_status "STEP 02 of 02: Returned '${INSTALL_NAME}'"
if [ "${TMP_STR}" == 'Exit' ] ; then
	if [ "${INSTALL_NAME}" == 'Mavericks' ] ; then
		echo; echo
		msg_info 'NOTE:'
		msg_status "Mavericks Installer *IS NOT* Supported"
	fi
    runExit 'Exit' ;
fi

sudo -v; echo
msg_info 'Completed Stage 1'

echo; echo
msg_info '## STAGE 2 of 4: Confirm Prerequisites ##'
msg_info '-----------------------------------------'
msg_status "STEP 01 of 02: Validate Installer Name..."
gotError="False"
INSTALL_TARGET=$( echo "Install_${INSTALL_NAME}" | sed 's/ //g' )
INSTALL_STICK="/Volumes/${INSTALL_TARGET}"
if [ -d "${INSTALL_STICK}" ] ; then
    err_msg="Unmount conflicting '${INSTALL_TARGET}' volume and rerun this script"
    gotError="True"
fi

TMP_STR='NotSet'
if [ "${gotError}" == 'False' ] ; then
    sudo -v; echo
    msg_status "STEP 02 of 02: Validate Misc Other..."
    # Check if using installer app for Yosemite to Sierra
    if [ "${USE_APP}" == 'Maybe' ] ; then
    	USE_APP='False'
    	if [ "${INSTALL_NAME}" == 'Sierra' ] ; then
    		TMP_STR='macOS'
    	elif [ "${INSTALL_NAME}" == 'El Capitan' ] || [ "${INSTALL_NAME}" == 'Yosemite' ] ; then
    		TMP_STR='OS X'
    	fi
    	if [ "${TMP_STR}" != 'NotSet' ] ; then
    		if installerExists "Install ${TMP_STR} ${INSTALL_NAME}.app" ; then
    			USE_APP='True'
    		fi
    	fi
    fi
    TMP_STR='NotSet'
    if [ "${USE_APP}" == 'False' ] ; then
    	# Ensure DMG is mounted
        if [ ! -d "/Volumes/${INSTALL_BASIC}" ] ; then
            err_msg="Mount the '${INSTALL_X}.dmg' file and rerun this script."
            gotError="True"
        fi
    else
    	# Note by Jeff Geerling
    	# Eject installer disks in case opened after download from App Store
    	# grep "partition_scheme" because "partition" finds too many lines
    	for disk in $(hdiutil info | grep /dev/disk | grep partition_scheme | cut -f 1); do
    		hdiutil detach -force ${disk}
    	done
    fi
fi

# Error/Exit Handling
if [ "${gotError}" == 'True' ] ; then
	echo; echo
	msg_info 'ERROR!!'
	msg_error "${err_msg}"
	runExit 'Error' ;
fi

sudo -v; echo
msg_info 'Completed Stage 2'

if [ "${USE_APP}" == 'True' ] ; then
	echo; echo
	msg_info '## STAGE 3 of 4: Find Installer ##'
	msg_info '----------------------------------'
    msg_status "STEP 01 of 01: Checking for Installer App..."
	if [[ "${INSTALL_NAME}" == "Monterey" || "${INSTALL_NAME}" == "Big Sur" || "${INSTALL_NAME}" == "Catalina" || "${INSTALL_NAME}" == "Mojave" ]] ; then
		if installerExists "Install macOS ${INSTALL_NAME}.app" ; then
            INSTALL_TYPE='macOS'
			TYPE_OSX='macOS'
		fi
	elif [[ "${INSTALL_NAME}" == "High Sierra" || "${INSTALL_NAME}" == "Sierra" ]] ; then
		# DA-TAG: The Sierras are odd with 'macOS' app name but 'OS X' elsewhere
		if installerExists "Install macOS ${INSTALL_NAME}.app" ; then
            INSTALL_TYPE='macOS'
			TYPE_OSX='OS X'
		fi
	elif [[ "${INSTALL_NAME}" == "El Capitan" || "${INSTALL_NAME}" == "Yosemite" ]] ; then
		if installerExists "Install OS X ${INSTALL_NAME}.app" ; then
            INSTALL_TYPE='OS X'
			TYPE_OSX='OS X'
		fi
	fi
	if [ "${TYPE_OSX}" == 'NotSet' ] ; then
		echo; echo
		msg_info 'ERROR!!'
		msg_error "Could not find valid installer app file"
		runExit 'Error' ;
	fi
	echo "Found Installer App for ${INSTALL_NAME}"
	VOL_BASE_DIR="/Volumes/${TYPE_OSX} Base System"
	VOL_BASE_SYS="${VOL_BASE_DIR}/BaseSystem"
	TMP_STR='NotSet'

	sudo -v; echo
	msg_info 'Completed Stage 3'

	echo; echo
    msg_info '## STAGE 4 of 4: Create ISO Image ##'
	msg_info '------------------------------------'
	createISO "Install ${INSTALL_TYPE} ${INSTALL_NAME}.app"
else
	echo; echo
	msg_info '## STAGE 3 of 4: Deconstruct Installer ##'
	msg_info '-----------------------------------------'
	msg_status "STEP 01 of 05: Clearing '${INSTALL_TEMP}'..."
	rm -rfv "${INSTALL_TEMP}"

	sudo -v; echo
	msg_status "STEP 02 of 05: Creating '${INSTALL_TEMP}'..."
    chiil_msg ;
	pkgutil --expand "/Volumes/${INSTALL_BASIC}/${INSTALL_X}.pkg" "${INSTALL_TEMP}"

	sudo -v; echo
	msg_status "STEP 03 of 05: Ejecting '${INSTALL_BASIC}'..."
	sudo diskutil eject "${INSTALL_BASIC}"

	sudo -v; echo
	msg_status 'STEP 04 of 05: Preparing and Attaching InstallESD...'
	hdiutil attach "${INSTALL_TEMP}/${INSTALL_X}.pkg/InstallESD.dmg"  -noverify -nobrowse -mountpoint "${INSTALL_ESD}"

	sudo -v; echo
	msg_status 'STEP 05 of 05: Preparing and Aligning BaseSystem...'
    chiil_msg ;
	sudo asr restore -source "${INSTALL_ESD}/BaseSystem.dmg" -target "/Volumes/${INSTALL_ID}" -noprompt -noverify -erase || true

	sudo -v; echo
	msg_info 'Completed Stage 3'

	echo; echo
	msg_info '## STAGE 4 of 4: Repackage Installer ##'
	msg_info '---------------------------------------'
	msg_status "STEP 01 of 04: Preparing Target..."
	diskutil rename "${INSTALL_BASE}" "${INSTALL_TARGET}"
	rm -v "${INSTALL_STICK}/System/Installation/Packages"

	sudo -v; echo
	msg_status 'STEP 02 of 04: Reconstituting ESD...'
    chiil_msg ;
    cp -rpv "${INSTALL_ESD}/BaseSystem.chunklist" "${INSTALL_STICK}/"
    cp -rpv "${INSTALL_ESD}/Packages" "${INSTALL_STICK}/System/Installation"
    cp -rpv "${INSTALL_ESD}/BaseSystem.dmg" "${INSTALL_STICK}/"
	hdiutil detach "${INSTALL_ESD}" || true

    sudo -v; echo
	msg_status 'STEP 03 of 04: Relabelling Volume and Updating VolumeIcon...'
	sudo bless --folder "${INSTALL_STICK}/System/Library/CoreServices" --label "${INSTALL_TARGET}"
	InstallIcon="${INSTALL_STICK}/${INSTALL_APP}/Contents/Resources/InstallAssistant.icns"
	if [ ! -f "${InstallIcon}" ]; then
        INSTALL_APP="${INSTALL_STICK}/Install OS X ${INSTALL_NAME}.app"
        InstallIcon="${INSTALL_APP}/Contents/Resources/InstallAssistant.icns"
        if [ ! -f "${InstallIcon}" ]; then
            INSTALL_APP="${INSTALL_STICK}/Install Mac OS X ${INSTALL_NAME}.app"
            InstallIcon="${INSTALL_APP}/Contents/Resources/InstallAssistant.icns"
            if [ ! -f "${InstallIcon}" ]; then
                INSTALL_APP="${INSTALL_STICK}/Install Mac OS ${INSTALL_NAME}.app"
                InstallIcon="${INSTALL_APP}/Contents/Resources/InstallAssistant.icns"
                if [ ! -f "${InstallIcon}" ]; then
                    INSTALL_APP="${INSTALL_STICK}/Install macOS ${INSTALL_NAME}.app"
                    InstallIcon="${INSTALL_APP}/Contents/Resources/InstallAssistant.icns"
            	fi
        	fi
    	fi
	fi
    if [ -f "${InstallIcon}" ]; then
        cp -v "${InstallIcon}" "${INSTALL_STICK}/.VolumeIcon.icns"
    else
        echo 'Skipped VolumeIcon Update ... Not Found'
    fi

	sudo -v; echo
	msg_status 'STEP 04 of 04: Finishing...'
    chiil_msg ;
	cd "${HOME}" || true
    sudo rm -rf "${INSTALL_TEMP}" || true
	sudo diskutil eject "${INSTALL_TARGET}" || true

	sudo -v; echo
	msg_info 'Completed Stage 4'
	runExit ;
fi

This worked great for creating a bootable USB for OSX Lion for an old 2013 Macbook Air. The process was smooth, easy to follow, and comprehensive. Would be happy to send you some $$$ as a tip if you accept that. Thank you for building and sharing this!

Dayo why did you skip Mavericks? Some people have legitimate Mavericks apps.

Hi ... Didn't have one at the time but IIRC, the one I did get had a different structure and initial attempts failed.
Didn't try too hard to sort it out and moved on given that Apple was not offering it like the others anyway.

Hi,thanks for this scripts.I made several bootable macos,but it's wired that some Volume icons do not show up,see attched photo.For Lion,when running the scripts,it shows:Skipped ... VolumeIcon not found.I check the path of InstallAssistant.icns,this icns exists

Is this path existing:

/Volumes/Lion Installer/Install OS X Lion/Contents/Resources/InstallAssistant.icns

@onekingnqueen ... Thanks for the report.

Should be fixed now.