if [[ ! "$PID" =~ ^[0-9]+$ ]] ; then
# that likely didn't work because of returning multiple processes
# try again, filtering by root processes (don't contain colon)
if [[ ! "$PID" =~ ^[0-9]+$ ]] ; then
# that likely didn't work because of returning multiple processes
# try again, filtering by root processes (don't contain colon)