Yeah, I'm more focused on keeping it in range than exactly matching the user's input. If they think results seem odd, turn on the verbose mode and see what happened.
I rarely use getopt(), and usually go for getopt_long(), but I'm not expert in either. I skipped getopt_long() here because I believe getopt() is a lot more portable. I seem to recall I needed to #ifdef some include files on one of the BSDs last time I tried it.
I'll probably make a proper repo, and include animations, sometime this weekend. I'll look into testing more edge cases then.
Elijah
------ too bad the video copyrights are so murky