Set Telnet Server nonblocking = false

Hey all,
I'm writing a telnet server. I think it should be obvious what it does. But, my clients keep getting disconnected whenever I use IO.getc because it is nonblocking and it's throwing an error.

How can I set my telnet server to have nonblocking=false?

my code is here:

There are errors galore, and I would greatly appreciate it if you ever wanted to criticize me to death.