title: Sync files with sqlite database qt c++
body: <p>I have many directories that I should sync with a sqlite db. The database should ever store the files content in these directories.
  To do this I've made a thread (lowest priority) that continuously looks for changes in the directories. However this thread uses 100% of cpu of one core.
  Is there a better way to sync files? Maybe a listener that emits a signal when a file will be created or removed?</p>
  
  <p>Thanks,
  Regards Andrea</p>