This code snipplet was originally from: http://www.debian-tutorials.com/bash-2-/bah-script-installupgrade-wordpress

installwp.sh

#!/bin/bash
#
# Homepage: http://www.debian-tutorials.com
# Email: contact@debian-tutorials.com
# Bash script to download and install or upgrade wordpress to specified directory.
install_wp ()
{
cd ~</pre>
<!--more-->
<pre>
mkdir wordpress
cd wordpress
wget https://wordpress.org/latest.tar.gz --no-check-certificate;
echo "Where would you like your new WordPress install to be located? Please Type the location(Eg:/var/www/) and press [ENTER]: "
read wordpress_dir
echo "Installing WordPress to $wordpress_dir";
    if [ ! -d "$wordpress_dir" ]; then
        mkdir $wordpress_dir
    fi
tar -zxvf latest.tar.gz -C $wordpress_dir
}
clean_up ()
{
cd ~/wordpress
rm latest.tar.gz
cd ~
rmdir wordpress
cd $wordpress_dir/wordpress
mv *.* $wordpress_dir
mv wp-admin $wordpress_dir
mv wp-content $wordpress_dir
mv wp-includes $wordpress_dir/
rmdir $wordpress_dir/wordpress
cd $wordpress_dir/wp-content
mkdir uploads
chmod 777 uploads -R
cd $wordpress_dir
touch $wordpress_dir/.htaccess
chmod -v 666 .htaccess
echo "Wordpress is now Installed to" . $wordpress_dir . "Enjoy!"
}
update_wp ()
{
day=`date +%Y_%m_%d`
cd ~
mkdir wordpress_tmp
cd wordpress_tmp
wget https://wordpress.org/latest.tar.gz --no-check-certificate;
echo "In what directory does WordPress already exist, that you would like updated? Please Type the location(Eg:/var/www/) and press [ENTER]: "
read update_dir
tar -zxvf latest.tar.gz -C $update_dir
cd ~/wordpress_tmp
rm latest.tar.gz
cd ~
rmdir wordpress_tmp
cd $update_dir
cp $update_dir/ $update_dir/../wordpress_backup_$day -R
cp $update_dir/../wordpress_backup_$day/wp-config.php $update_dir
# Go to backup directory and remove the new install of WP
cd $update_dir/../wordpress_backup_$day
rm wordpress -rf
# back to the update directory
cd $update_dir/wordpress
#remove wp-admin and wp-includes
cd $update_dir
rm wp-admin -rf
rm wp-includes -rf
cd $update_dir/wordpress
mv wp-admin $update_dir
mv wp-includes $update_dir
#remove the extra updated directoroies
rm $update_dir/wordpress/ -rf
echo "Upgrade complete! Backup can be found in $update_dir/../$update_dir_backup_$day"
}
if ["$(id -u)" = "0"]; then {
echo "You are root we will continue" 2>&1
 install_wp
 clean_up
 exit
 }
else
{
read -p "If the location you want to install wordpress to requires Root access, Please press 'N' and run this script again as root, or 'Y' to run the script without root (y/n)? "
[ "$REPLY" == "n" ] & exit ||
[ "$REPLY" == "y" ] &
echo "Do you wish to install WordPress [Yes] or update [No]? Type 1 or 2 and press [ENTER]"
select yn in "Yes" "No"; do
    case $yn in
        Yes ) install_wp && clean_up && break;;
        No ) update_wp && break;;
    esac
done
}
fi
exit 1;