thread.rb

#!/usr/bin/env ruby

$var = 0
puts "var: #{$var}"

a = Thread.start do; 5.times do
	$var += 1
	puts "a: #{$var}"
	Thread.pass
end;end

b = Thread.start do; 5.times do
	$var += 1
	puts "b: #{$var}"
	Thread.pass
end;end

a.join
b.join
puts "var: #{$var}"