You are right, the sleep functions apply only to “this_thread”. What confused me is the comment for the two functions, which refer to the thread as “t” and not “this_thread”; which also matches the naming used for the “is_joinable” function, where it is not the current thread.

So I thought it’s a way to do back pressure across threads, which could be useful, but I was clearly wrong. My bad, but also not a great choice of naming things in the original article.

Then again, if you can only put the current thread to sleep, why have a function for it? Why not call sleep directly?