Added functionality for reverse DNS lookup. There is currently a slight bug in the formatting output. I also don't know how you want it to be outputted period so I just added it on after. The grep command seems to be deterministic, it doesn't always succeed.
I suggest adding the reverse DNS lookup functionality with a command line flag.
You are exactly correct. Command line flags are coming. I'd also like to do this with system calls if possible, rather than spawning a process but we can change that later on down the road.
Added functionality for reverse DNS lookup. There is currently a slight bug in the formatting output. I also don't know how you want it to be outputted period so I just added it on after. The grep command seems to be deterministic, it doesn't always succeed.
I suggest adding the reverse DNS lookup functionality with a command line flag.