http://stackoverflow.com/questions/3043978/bash-how-to-check-if-a-process-id-pid-exists
https://bugzilla.redhat.com/show_bug.cgi?id=835838
http://stackoverflow.com/questions/3043978/bash-how-to-check-if-a-process-id-pid-exists
https://bugzilla.redhat.com/show_bug.cgi?id=835838