Hi Florian,

On 3/25/14 5:18 AM, Florian Weimer wrote:
On 03/24/2014 10:11 PM, roger riggs wrote:

 From the scope of the JEP, a fairly simple API seems sufficient.
  - Enumerate the direct children
  - The rest of the functions are similar to Process
    - to terminate a process, forcibly and normally
    - to destroy a process and all of its children recursively
    - to check if one is alive
    - to waitFor for termination and retrieve the exit status

On Linux, I think you need to use obscure mechanisms to make this iteration reliable (cgroups perhaps). There is no openpid() or similar mechanism that allows you to obtain a stable handle.
Given that processes are asynchronous in creation and termination, I don't think 'reliable' listing is possible. In a pathological case, processes can be created
as fast/faster than they can be terminated.

Somewhat relatedly, it would make sense to make Process auto-closeable, so that you can make sure that no non-Java resources are retained. Right now, this seems to require calling destroyForcibly().waitFor().
That's worth looking at a close() method could have that compound behavior.

It would be nice if there was a way to directly pipe the output of one process to the input of another process. I think that even with Java 8, this still needs an explicit copy loop.
That's similar to other requests to directly feed or consume from the subprocess from
a file or pipe.

Thanks, Roger


Reply via email to