- allways check for whole system state (all errors / warnings)
-> e.g. an error does not hide an other error or warning
- send machine event only once
- store sent events in a QSet-container
- clear this container if no error / warning is detected
Note: there is currently no message for releasing a certain single error
/ warning. So it is no worth in removing a single entry in
QSet-container. This is a task for later program versions.