createmyguest.sh script, original by nbalonso (https://gist.github.com/nbalonso/5696340)

gistfile1.sh

#!/bin/bash

# Original script by Noel B. Alonso: https://gist.github.com/nbalonso/5696340

#variables
DSCL="/usr/bin/dscl"
SECURITY="/usr/bin/security"
LOGGER="/usr/bin/logger"

# Determine OS version
OSVERS=$(sw_vers -productVersion | awk -F. '{print $2}')

# Set the account shortname
USERNAME="kiosk"

# Set the name which is displayed in System Preferences for the account
DISPLAYNAME="Kiosk User"

# Set the account's UID
GUESTUID="600"

# Set the account's GID
GUESTGROUPID="600"

if [[ ${OSVERS} -lt 6 ]]; then
  ${LOGGER} -s -t create"${USERNAME}".sh "ERROR: The version of OS X running on this Mac is not supported by this script. User account not created."
fi

if [[ ${OSVERS} -eq 6 ]]; then
	${LOGGER} -s -t create"${USERNAME}".sh "INFO: Creating the "${USERNAME}" user account on Mac OS X 10.${OSVERS}.x"
	${DSCL} . -create /Users/"${USERNAME}"
	${DSCL} . -create /Users/"${USERNAME}" UserShell /bin/bash
	${DSCL} . -create /Users/"${USERNAME}" RealName "${DISPLAYNAME}"
	${DSCL} . -create /Users/"${USERNAME}" UniqueID "${GUESTUID}"
	${DSCL} . -create /Users/"${USERNAME}" PrimaryGroupID "${GUESTGROUPID}"
	${DSCL} . -create /Users/"${USERNAME}" NFSHomeDirectory /Users/"${USERNAME}"
	${DSCL} . -create /Users/"${USERNAME}" RecordType dsRecTypeStandard:Users
	${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_defaultLanguage en
	${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_guest true
	${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_writers__defaultLanguage "${USERNAME}"
	${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_writers_jpegphoto "${USERNAME}"
	${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_writers_LinkedIdentity "${USERNAME}"
	${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_writers_picture "${USERNAME}"
	${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_writers_UserCertificate "${USERNAME}"
	${DSCL} . -create /Users/"${USERNAME}" AppleMetaNodeLocation /Local/Default
	#setting up an empty password and giving local Kerberos some time to process it
	${DSCL} . -passwd /Users/"${USERNAME}" ''
	sleep 2
fi

if [[ ${OSVERS} -ge 7 ]]; then
		${LOGGER} -s -t create"${USERNAME}".sh "INFO: Creating the "${USERNAME}" user account on Mac OS X 10.${OSVERS}.x"
		${DSCL} . -create /Users/"${USERNAME}"
		${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_defaultLanguage en
		${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_guest true
		${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_writers__defaultLanguage "${USERNAME}"
		# Adding the _writers_LinkedIdentity attribute for Macs running Mac OS X 10.7.x. This
		# attribute is not needed on 10.8.x and later.
		if [[ ${OSVERS} -eq 7 ]]; then
			${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_writers_LinkedIdentity "${USERNAME}"
		fi
		${DSCL} . -create /Users/"${USERNAME}" dsAttrTypeNative:_writers_UserCertificate "${USERNAME}"
		${DSCL} . -create /Users/"${USERNAME}" AuthenticationHint ''
		${DSCL} . -create /Users/"${USERNAME}" NFSHomeDirectory /Users/"${USERNAME}"
		#setting up an empty password and giving local Kerberos some time to process it
		${DSCL} . -passwd /Users/"${USERNAME}" ''
		sleep 2
		${DSCL} . -create /Users/"${USERNAME}" Picture "/Library/User Pictures/Nature/Leaf.tif"
		${DSCL} . -create /Users/"${USERNAME}" PrimaryGroupID "${GUESTGROUPID}"
		${DSCL} . -create /Users/"${USERNAME}" RealName "${DISPLAYNAME}"
		${DSCL} . -create /Users/"${USERNAME}" RecordName "${USERNAME}"
		${DSCL} . -create /Users/"${USERNAME}" UniqueID "${GUESTUID}"
		${DSCL} . -create /Users/"${USERNAME}" UserShell /bin/bash
		#Adding the keychain item that allows "${USERNAME}" to login in 10.7 and later.
		${SECURITY} add-generic-password -a "${USERNAME}" -s com.apple.loginwindow.guest-account -D "application password" /Library/Keychains/System.keychain
fi

${LOGGER} -s -t create"${USERNAME}".sh "INFO: Exiting"

exit 0