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Subject: Re: cluts: strerror_r() test
Date: Thu, 14 Jul 2011 21:35:06 +0200
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On 07/14/2011 07:55 PM, Rich Felker wrote:
> On Thu, Jul 14, 2011 at 12:41:35PM +0200, Luka Marčetić wrote:
>> one). Strerror_r implementations are free to redirect a passed
>> pointer to immutable memory if size(buflen) argument is sufficiently
> I don't see how this can be. [...]

Neither does the standard, ##C lied to me ;-)

>> large. Of course, wanting to write to s[size-1] would SIGSEGV in
> Actually it would probably just corrupt malloc data structures and
> lead to havoc much later in the program. To test you could use a trick
> like the string function tests, but that's really overkill. Just
> allocating a buffer that's large enough, pre-filling it with an
> unusual value, and calling the function with a shorter length
> parameter should work. Then you can check that none of the fill bytes
> were clobbered past the allowed length.
>
> I hope this makes sense...

Unfortunately, no, I don't get any of it.