**Input**: The *runid* (integer) of the running instance inspected.
**output**: An object describing instance state. It contains:
-the runid (integer), the id of the running application (string),
+the runid (integer), the pids of the processes as an array starting
+with the group leader, the id of the running application (string),
the state of the application (string either: "starting", "running", "stopped").
Example of returned state:
{
"runid": 2,
+ "pids": [ 435, 436 ],
"state": "running",
"id": "appli@x.y"
}