I currently have an application that opens several .csv files and stores them in temporary holders (QHash, QList...). The problem I have seen is that when the user clicks the 'Save' option I try and open the files and save all the information contained in the temporary objects to the corresponding .csv files. If the user has one of those files open in say Microsoft excel how do I control the way that event is handled? Is there a special function in QFile or QTextStream that I can call to check this status? Right now very strange behavior happens because one file might get saved while the others aren't so the files are no longer in sync and the application just crashes which is obviously not a desired behavior.