Re: free()

Richard Heathfield wrote:

Chris Dollin said:

Beej wrote:

void delete_goat(GOAT *g)
{
free(g);
g = NULL;
}

This being a place where the assignment of NULL is completely
pointless.

...but then it's a pointless function anyway.

It frees the store its argument points to and names what's
going on, so the /function/ isn't pointless.

I write destructors like this:

void goat_delete(GOAT **g)
{
if(g != NULL)
{
if(*g != NULL)
{
GOAT *p = *g; /* purely for notational convenience */
horn_delete(&p->horn);
trollgun_delete(&p->trollgun);
leg_delete(&p->leg);
free(p);

*g = NULL; /* *not* a pointless assignment */
}
}
}

Interesting. I'm trying to articulate why I find that overkill.
I /think/ it's that where I free something, either the place
I'm freeing it from is about to evaporate (as in your horn,
leg, and trollgun), so the assignment doesn't help, or I'm
about to assign a new value to that place, ditto. Probably because
we're writing different kinds of code. With a shared goal:
"don't let invalid pointers screw you up - get rid of them PDQ".

--
Chris "electric hedgehog" Dollin
A rock is not a fact. A rock is a rock.

.

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