BaltimoreGo Challenge: Build a Port Scanner

requirements.md

Your challenge is to write a port scanner in Go that uses a worker pool to efficiently scan multiple ports concurrently. It should meet the following requirements:

1. Accepts a range of ports to scan as an argument (e.g. ./portscan -ports 8080-9090)
2. Accepts a number of workers to use for performing the scans (e.g. ./portscan -workers 100)
3. Outputs <PORT> CLOSED for closed ports as they are discovered.
4. Outputs <PORT> OPEN for open ports as they are discovered.
5. Extra credit: How could you informed the user of your port scanner of the likely service running on the open ports? (e.g. 5432 is likely a PostgreSQL server)

Hints:

1. Use the flags package to capture invocation parameters.
2. Rely on the net package.
3. Make use of channels for communication across goroutines.