So again, the Wikipedia picture provides some context. I think
about those ovals, not about the enclosing boxes.
Oops. In that picture, the original caller is a small rectangle, not
oval, labeled "Main program". Personally, I would have labeled it
And of course the thing labeled "Library function" doesn't really have
to be in a software library. All three functions can be in the same
"program", and all can be in the same source member. The concept
The central concept is that a function can be passed as a parameter.
The passed function is the callback function. (So yeah, in my
opinion, a better term for "callback function" would be "passed