Re: Using the return value of strlcpy() and strlcat()

Tom Lane <tgl@sss.pgh.pa.us> writes:

> Ashwin Agrawal <aagrawal@pivotal.io> writes:
>> On Wed, Mar 13, 2019 at 9:51 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> I don't think that's a safe transformation: what strlcpy returns is
>>> strlen(src), which might be different from what it was actually
>>> able to fit into the destination.

Yeah, Andrew Gierth pointed this out on IRC as well.

>>> Sure, they're equivalent if no truncation occurred; but if we were
>>> 100.00% sure of no truncation, we'd likely not bother with strlcpy.
>
>> So, if return value < length (3rd argument) we should be able to use the
>> return value and avoid the strlen, else do the strlen ?
>
> Mmm ... if there's a way to do it that's not messy and typo-prone,
> maybe.  But I'm dubious that the potential gain is worth complicating
> the code.  The strings involved aren't usually all that long.

Please consider this patch withdrawn.

- ilmari
-- 
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