This shell script can check the list to see which domains are registered and which are free.

To use this script, make sure to install the whois package beforehand.

To install whois on Ubuntu, Debian, and Linux Mint:

sudo apt install whois

To install whois on CentOS, Fedora, AlmaLinux, and Red Hat:

sudo dnf install whois

To install whois on Arch Linux and Manjaro:

sudo pacman -S whois

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