Re: when can realloc fail?

On 1 Apr 2007 11:50:05 -0700, banansol@xxxxxxxxxxxx wrote:

Hi,
I just want to get this right.
A call to realloc() will return NULL on error and the original memory
is left untouched,
both when requesting a larger or a smaller size that the original,
right?

It returns NULL if the space cannot be allocated. Whether it is due
to an error or not is something else.

But a call to realloc() with size set to zero is equivalent to free(),
with returns void.

No it is not. Read the last sentence of 7.20.3 again.

Does that mean that a call to realloc() can fail when shinking memory
except when
shrinking it to zero in which case it will always succeed?

No. Success is not guaranteed.


Thanks!


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