https://tldp.org/LDP/abs/html/
https://tldp.org/LDP/abs/html/awk.html#AWKREF
https://www.golinuxcloud.com/run-while-loop-until-specific-time-shell-bash/
https://linuxhint.com/50_sed_command_examples/
https://rez0.blog/hacking/2021/02/08/bash-aliases-command-line-tools-3.html
https://www.howtogeek.com/427982/how-to-encrypt-and-decrypt-files-with-gpg-on-linux/