#!/bin/bash

# adduser--Adds a new user to the system, including building their
#          home directory, copying in default config data, etc.
#          For a standard Unix/Linux system, not Mac OS X.

pwfile="/etc/passwd"    
shadowfile="/etc/shadow"
gfile="/etc/group"
hdir="/home"

if [ "$(id -un)" != "root" ] ; then
  echo "Error: You must be root to run this command." >&2
  exit 1
fi

echo "Add new user account to $(hostname)"
echo -n "login: "     ; read login

# The next line sets the highest possible user ID value at 5000,
#   but you should adjust this number to match the top end 
#   of your user ID range.

uid="$(awk -F: '{ if (big < $3 && $3 < 5000) big=$3 } END { print big + 1 }' $pwfile)"
homedir=$hdir/$login

# We are giving each user their own group, so gid=uid
gid=$uid

echo -n "full name: " ; read fullname
echo -n "shell: "     ; read shell

echo "Setting up account $login for $fullname..."

echo ${login}:x:${uid}:${gid}:${fullname}:${homedir}:$shell >> $pwfile
echo ${login}:*:11647:0:99999:7::: >> $shadowfile

echo "${login}:x:${gid}:$login" >> $gfile

mkdir $homedir
cp -R /etc/skel/.[a-zA-Z]* $homedir
chmod 755 $homedir
chown -R ${login}:${login} $homedir

# Setting an initial password
exec passwd $login