From: "Daniel Jacobowitz" <dan@debian.org>
> On Thu, May 30, 2002 at 12:32:47PM -0700, Justin Carlson wrote:
> > A fair number of places in the headers, we have stuff like this:
> >
> > void (*_some_fn)(int arg1, int arg2);
> > #define some_fn(arg1, arg2) _some_fn(arg1, arg2)
> >
> > Why do we do this, as opposed to:
> >
> > void (*some_fn)(int arg1, int arg2);
> >
> > Both syntaxes result in being able to say
> >
> > some_fn(1, 2);
> >
> > but the latter is both clearer and shorter. Is there some deep,
> > mystical C reason that we use the former, or did someone do it that way
> > a long time ago and no one has changed it?
>
> At a guess, this prevents taking the address of the function
> unintentionally...
More likely, some ancient early version of the code was
written with a single global function, some_fn(), and it
was easier to override it with a pointer indirection in
the header than to hunt down and change all invocations.
Sometimes that's good software engineering. Sometimes
it's just laziness...
Kevin K.
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