Ruby: wait for any child process to finish

Question

Is there a way to wait for any (not all!) child process to finish? I am writing a Rake task that spawns several child processes and I want to start an action as soon as the first child process is finished.

Answer 1

Just call

Process.wait

With no arguments. This waits for any child process to terminate (see docs)

You can also wait for children of a specific process group - possibly useful if you need more control.