Re: Callback

[Vernon Hamberg <vhamberg@xxxxxxxxxxxxxxx>]

John

As I wrote my reply, I was thinking about whether we can specify the 
address of a procedure in another service program, say. I didn't bring 
it up, because I wasn't sure, and I thought it'd confuse the issue. 
Generalizing to that would have benefits similar to what we espouse 
already for service programs.

I'll still go with the callback term - I could even say that the called 
party is calling back to someone known to the calling party. It does 
seem to get a bit precious, however, and the traditional understanding 
works for me, although I hear what you are saying.

Vern

On 10/15/2012 5:33 PM, John Yeung wrote:
> On Mon, Oct 15, 2012 at 5:46 PM, Vernon Hamberg
> <vhamberg@xxxxxxxxxxxxxxx> wrote:
> > The easiest example I use - the almost-only-one, actually, is when I use
> > the qsort API - when you call qsort, you tell it what data is to be
> > sorted, how long each element is, and a pointer to a procedure that will
> > compare 2 elements and return either that they are the same or that one
> > or the other is larger. That procedure is the callback - maybe we can
> > think of it as a CALL BACK to the caller of qsort. qsort walks through
> > the elements and passes pairs of them to the callback procedure.
> I have never really liked the explanation that the called function is
> "calling back" to the original caller.  Yes, that's where the term
> came from, but I don't think it emphasizes the right things.