Read keypresses from user in terminal, including arrow keys using pure Ruby. This has since been folded into a much more robust gem called Remedy. https://rubygems.org/gems/remedy & https://github.com/acook/remedy

keypress.rb

require 'io/console'

# Reads keypresses from the user including 2 and 3 escape character sequences.
def read_char
  STDIN.echo = false
  STDIN.raw!

  input = STDIN.getc.chr
  if input == "\e" then
    input << STDIN.read_nonblock(3) rescue nil
    input << STDIN.read_nonblock(2) rescue nil
  end
ensure
  STDIN.echo = true
  STDIN.cooked!

  return input
end

# oringal case statement from:
# http://www.alecjacobson.com/weblog/?p=75
def show_single_key
  c = read_char

  case c
  when " "
    puts "SPACE"
  when "\t"
    puts "TAB"
  when "\r"
    puts "RETURN"
  when "\n"
    puts "LINE FEED"
  when "\e"
    puts "ESCAPE"
  when "\e[A"
    puts "UP ARROW"
  when "\e[B"
    puts "DOWN ARROW"
  when "\e[C"
    puts "RIGHT ARROW"
  when "\e[D"
    puts "LEFT ARROW"
  when "\177"
    puts "BACKSPACE"
  when "\004"
    puts "DELETE"
  when "\e[3~"
    puts "ALTERNATE DELETE"
  when "\u0003"
    puts "CONTROL-C"
    exit 0
  when /^.$/
    puts "SINGLE CHAR HIT: #{c.inspect}"
  else
    puts "SOMETHING ELSE: #{c.inspect}"
  end
end

show_single_key while(true)

Great snippet! I'm facing a problem however… This is my output

right
left
app3
right
left
up
down
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle
middle

As you can see above, the middle (enter key) remains pressed for indefinitely amount of time. I'm not sure what's causing this. It's not just the enter key, happens with any. Wondering why. Any idea?

Very helpful, thank you.

Awesome! I just downloaded it, and it works great!

Doesn't work on Windows

Yes, can confirm it doesn't work on Windows, either

super useful, 🙏

I'm glad this has helped people!

If you discover something that is also broken in Remedy please report it!

Anyone found the windows solution yet?