bananenkeyboard/piconfig/readonly.sh

apt remove -y --purge triggerhappy logrotate dphys-swapfile cron
apt autoremove -y --purge
apt install -y busybox-syslogd
apt remove -y --purge rsyslog
sh -c 'echo -n "fastboot noswap ro" >>/boot/cmdline.txt'
rm -rf /var/lib/dhcp/ /var/run /var/spool /var/lock /etc/resolv.conf
ln -s /tmp /var/lib/dhcp
ln -s /tmp /var/run
ln -s /tmp /var/spool
ln -s /tmp /var/lock
touch /tmp/dhcpcd.resolv.conf; ln -s /tmp/dhcpcd.resolv.conf /etc/resolv.conf
rm /var/lib/systemd/random-seed
ln -s /tmp/random-seed /var/lib/systemd/random-seed
sed -i 's#ExecStart=/lib/systemd/systemd-random-seed load#ExecStartPre=/bin/echo "" >/tmp/random-seed\nExecStart=/lib/systemd/systemd-random-seed load#' /lib/systemd/system/systemd-random-seed.service
systemctl daemon-reload
systemctl disable console-setup
sed -i 's#\(.*PARTUUID.*defaults\)\(.*\)#\1,ro\2#' /etc/fstab
cat <<EOT >>/etc/fstab
 
tmpfs           /tmp            tmpfs   nosuid,nodev         0       0
tmpfs           /var/log        tmpfs   nosuid,nodev         0       0
tmpfs           /var/tmp        tmpfs   nosuid,nodev         0       0
EOT

cat <<"EOT" >>/etc/bash.bashrc
# set variable identifying the filesystem you work in (used in the prompt below)
set_bash_prompt(){
    fs_mode=$(mount | sed -n -e "s/^\/dev\/.* on \/ .*(\(r[w|o]\).*/\1/p")
    PS1='\[\033[01;32m\]\u@\h${fs_mode:+($fs_mode)}\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
}
 
alias ro='sudo mount -o remount,ro / ; sudo mount -o remount,ro /boot'
alias rw='sudo mount -o remount,rw / ; sudo mount -o remount,rw /boot'
 
# setup fancy prompt
PROMPT_COMMAND=set_bash_prompt
EOT

cat <<EOT >>/etc/bash.bash_logout
sudo mount -o remount,rw /
history -a
sudo mount -o remount,ro /
sudo mount -o remount,ro /boot
EOT