DragonFly kernel List (threaded) for 2004-11
Re: learning dragonfly or C...
Magnus Eriksson wrote:
On Thu, 11 Nov 2004, Devon H. O'Dell wrote:
vpp = &vp
is ``dereferencing'' vp. Dereferencing effectively provides the address
in memory of a variable.
*bar = 3; /* Change bar to 3 */
This time, we ``dereferenced'' our variable foo (and, on a sidenote, I
don't know why it's called dereferencing, I think it's a horrible name
and substitute it mentally with ``grab the address of'' whenever I see
It's called dereferencing because a pointer is a reference to something,
and dereferencing is the act of doing away with the reference
(de-referencing) and handling what is actually pointed to instead. So the
opposite of what you said really. Did you get enough sleep tonight? :-)
Oh, right. I did get enough sleep tonight, but I haven't had my cup of
coffee yet, so that must be it ;).
(but *bar = 3 in modfunction() is dereferencing bar though, if that's
what you meant.)
Nope, I really just missed the coffee :\.
I have no idea what the opposite operation (&) is called. Referencing?
Yeah, prefixing with an & is creating a reference; I suppose that _is_
what that's called. Which is why I (correctly) specified somewhere else
that we were passing it by reference.
Oh well. The rest of the example is correct. (This is why people get
confused with C. Nobody explains pointers right the first time.)