Blogged by Ujihisa. Standard methods of programming and thoughts including Clojure, Vim, LLVM, Haskell, Ruby and Mathematics written by a Japanese programmer. github/ujihisa As the previous posts of this blog, ruby 1.9's Kernel.spawn is very useful. I ported it to ruby 1.8 partly. How about on JRuby? Currently there are two ways of using spawn on JRuby, but both of them have problem. fork + exec +