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 + spawn-for-legacy library
I made a wrapper library spawn-for-legacy which provides ruby 1.9 style spawn, using fork and exec.
If JRuby has fork and exec, you can use spawn-for-legacy. Unfortunatelly when you use fork on JRuby, you have to set a command line option to JRuby interpreter.
