I suggest a pointer to double as an additional argument to `QFile::Copy`, `QFile::Move` and compress utilities (`qCompress` and `qUncompress`). Make the argument default to `nullptr` so the backward compatibility is no broken. Report the progress of the operation between 0.0 and 1.0. The progress can be watched then using a timer on a separated thread, for example. I've implemented such feature by my own by adding some lines to the respective Qt Code. It's not difficult, at least for the `QFile` functions.