[tz] mktime() clarification

[brian.inglis at systematicsw.ab.ca]

On 2024-03-25 19:53, Dag-Erling Smørgrav wrote:
> "brian.inglis--- via tz" <tz at iana.org> writes:
>> It would be more informative to state the platform and compiler you
>> used, show the results you got, and explain what you think it means.
> 
> I didn't expect my audience to be wilfully obtuse.  As I've already
> stated and emphasized, POSIX does not guarantee or require that errno is
> not modified by a successful call.  Given the input from my example,
> tzcode will set errno to EOVERFLOW before returning successfully.

So you are running tzcode mktime on some unspecified platform, compiler, and 
library, and that implementation happens to return that result, unless it 
happens that implementation's printf set errno to EOVERFLOW, before printing it.

Other platforms, libraries, and mktime implementations may produce different 
results: one platform I tested set errno = 2 ENOENT as posixrules is not 
installed, but time_t was as expected.


-- 
Take care. Thanks, Brian Inglis              Calgary, Alberta, Canada

La perfection est atteinte                   Perfection is achieved
non pas lorsqu'il n'y a plus rien à ajouter  not when there is no more to add
mais lorsqu'il n'y a plus rien à retirer     but when there is no more to cut
                                 -- Antoine de Saint-Exupéry