ruby で外部プログラムを実行する例

run.rb

# See http://refm.rubicle.net/sp/1.9.3/class/Open3
require 'open3'

puts "====== system ======"
ret = system('ps > /tmp/1')
puts ret
puts File.read('/tmp/1')

puts "====== Open3.capture3 ======"
so, se, st = Open3.capture3('ps')
puts "----- stdout ----"
puts so
puts "----- stderr ----"
puts se
puts "----- stat ----"
puts st