Enables fast user-switching for all macOS user

enable_fast_user_switching.sh

#!/bin/bash

# This script is designed to be run as root from a mgmt system like Addigy.

# Change the field separator to newline for usernames with directories
OIFS=$IFS
IFS=$'\n'

# Iterate through all users
for user in $(dscl . list /Users UniqueID | awk '$2 >= 500 {print $1}'); do
    userHome=$(dscl . read /Users/"$user" NFSHomeDirectory | awk '{print $2}')
    if [ $(defaults read "${userHome}/Library/Preferences/com.apple.systemuiserver.plist" 2> /dev/null | grep -i user.menu) == "" ]; then
        echo "Applying fast-user settings for user:$user"
        touch "${userHome}/Library/Preferences/com.apple.systemuiserver.plist"
        defaults write "${userHome}/Library/Preferences/com.apple.systemuiserver.plist" menuExtras -array-add '<string>/System/Library/CoreServices/Menu Extras/User.menu</string>'
    fi
done

# Set the global fast-user setting and reset the System settings to make it
# show immediately
defaults write /Library/Preferences/.GlobalPreferences MultipleSessionEnabled -bool Yes
killall -HUP SystemUIServer

# Reset the separator
IFS=$OIFS

I need to improve this with a more robust loop through user directories.

Improved looping through users. Line 11 still needs some work. I don't think it works if there are spaces in the home directory. Maybe I just need to push it through a sed that drops the beginning of the line as I believe that is the same every time.