Task: DNS Subdomain Underscore Validation Tool

Task: DNS Subdomain Underscore Validation Tool: a task in Terminal-Lego-15k (Harbor dataset). Create a shell script that validates whether domain names and subdomains comply with DNS naming standards, with a specific focus on the rules regarding underscore ( ) characters in subdomains.

The task

Create a shell script that validates whether domain names and subdomains comply with DNS naming standards, with a specific focus on the rules regarding underscore (`_`) characters in subdomains.

Part of PrimeIntellect/Terminal-Lego-15k.