Linux - Change Username

changeusername.sh

#!/bin/bash

echo "Enter the name of the OLD user and press [ENTER]: "
read olduser
echo "Enter the name of the NEW user and press [ENTER]: "
read newuser

echo "Killing all processes for $olduser"
pkill -u $olduser

echo "Changing $olduser to $newuser"
usermod -l $newuser $olduser

echo "Changing group under old username $olduser"
groupmod -n $newuser $olduser

echo "Changing home directory to /home/$newuser"
usermod -d /home/$newuser -m $newuser

echo "Checking old id"
id $olduser
echo "Checking new id"
id $newuser

Useful for changing the default 'pi' user on the Raspberry Pi.