RFR 9: 8003488 Add Process.getPid

[roger riggs]

Hi,

For system local process identifiers, all of the systems I'm aware are
32 bit integers,  printed and parsed in decimal for ease of use.
I would describe the native pid as:
     The native process id is the identifier commonly used in the
     operating system APIs and commands to show the status of and
     manage processes; typically a decimal number with 1 to 6 digits.

The Apollo system used a string to be able to uniformly address
processes across  hosts and it was parseable to host and decimal pid.

I anticipate a ProcessHandle type with methods to check if the process 
is alive,
to destroy it, wait for it to terminate, etc.
It would be a supertype of Process but not all ProcessHandles would be 
processes
since they were not created by Process/ProcessBuilder and have different
security concerns and checks.
ProcessHandles would be returned from factory methods like current(long pid)
or current().   If Java is ported to a system with non-numeric process 
identifiers
it would be viable to add appropriate factory methods.

Roger

On 5/12/2014 5:01 PM, Alan Bateman wrote:
> On 12/05/2014 20:44, roger riggs wrote:
>> Please review and comment on this long requested addition to provide the
>> native process id of a spawned Process.
>>
>> Webrev: http://cr.openjdk.java.net/~rriggs/webrev-getpid-8003488/
>> Issue:  https://bugs.openjdk.java.net/browse/JDK-8003488
> I think the representation of the pid needs consideration - we need to 
> be happy that using a long is the right thing to do and won't cause us 
> problems in the future and won't conflict with other APIs that we 
> might add in this area.
>
> In terms of spec then it might be helpful to say a bit more to define 
> a "native process id", even in an abstract way.
>
> -Alan
>
>