Converting from four command executions to one #14

To avoid possible inconsistencies in the results which can appear from processes being started/killed while the four ps executions are done, wouldn't it be preferable to get all the data from a single ps and process it all at once?

In fact I think that may be why the build of the pull request #13 is breaking. On of the ps processes is identifying another one of the ps executions. It may have become more frequent in that pull request due to the fact that it implements a fifth ps execution.