Problem
You would like to find out your public IP from the command line without using an online service
Solution
Use dig like the following line (taken from https://www.cyberciti.biz/faq/how-to-find-my-public-ip-address-from-command-line-on-a-linux/):
dig +short myip.opendns.com @resolver1.opendns.comyou could also add it as an alias:
alias myip=”dig +short myip.opendns.com @resolver1.opendns.com”