I agree with @blainesch that this is a good preparation for chaining commands.

I'd prefer to use [`Process.wait2`](http://www.ruby-doc.org/core-1.9.3/Process.html#method-c-wait2) though, because it makes the relationship between the child process and the exit status more explicit than `Process.wait` and `$?` does.

Something like this:

    pid, status = Process.wait2(pid)
    status.success?