From: "Peña, Botp" <botp@...>
Date: 2007-03-17T13:22:00+09:00
Subject: Re: Trapping ESC key

From: I G [mailto:rubycrazy@gmail.com] :
# I am stuck and can't find a simple and portable way to trap 
# the ESC key. Any
# pointers, help is most appreciated. The code I have now is -
# 
# require 'Win32API'
# def getchar
#   char = Win32API.new("crtdll", "_getch", [], 'L').call
#   if char == 27 # ESC key
#     exit
#   end
# end
# 
# i = 0
# loop do
#   print "#{i+=1}, "
#   getchar
# end

can you try this sample?

C:\family\ruby\key_press>cat -n a1d.rb
     1  #------------------------------
     2  require 'Win32API'
     3
     4  @@kbhit = Win32API.new("msvcrt", "_kbhit", [], 'I')
     5  @@getch = Win32API.new("msvcrt", "_getch", [], 'I')
     6
     7  def capture_key
     8     unless @@kbhit.call.zero?
     9        yield @@getch.call
    10     end
    11  end
    12
    13  KEY_Esc = 27
    14  $stdout.sync=true
    15
    16  i=0
    17  loop do
    18     capture_key do |key|
    19        puts "keypressed: value #{key}, char #{key.chr}" if $DEBUG
    20        if key == KEY_Esc
    21           puts "Escaping key pressed. Exiting..." if $DEBUG
    22           exit
    23        end
    24     end
    25     sleep 1  #delay it since it's too fast :)
    26     puts "#{i+=1}"
    27  end
    28  #------------------------------

C:\family\ruby\key_press>ruby -d a1d.rb
1
2
3
4
keypressed: value 117, char u
5
keypressed: value 101, char e
6
7
8
keypressed: value 119, char w
9
10
keypressed: value 120, char x
11
12
keypressed: value 27, char ?
Escaping key pressed. Exiting...

C:\family\ruby\key_press>

Hth.
kind regards -botp