Ah, I see what you want to do now. I hadn't realized that that was something you really wanted to do, rather than just a leftover of something you had tried a while ago.

I don't know really how to do what you wanted to do. std::time seems like a crude mechanism since it only provides seconds. It would be better to use the dealii::Timer class for this purpose. But in the end, I think this is too much detail, both for output and for readability of the code. Would you be amenable to take this piece out of the code and keep it in your private repository for now?