Re: [PATCH] tempfile: avoid "ferror | fclose" trick

> I'm also not sure that it's all that useful to distinguish errors from
> fwrite() versus fclose(). In practice, errors will come from write() in
> either case, and the caller does not have much control over when the
> flushing happens. So any error saying "error closing file" is probably
> assuming too much anyway. It should be "error writing file".

>> We _could_ clear errno to allow caller to tell them apart, though,
>> if we wanted to ;-)
>
> Hmm. So basically "errno = 0" instead of EIO? That at least has the
> advantage that you can tell it apart from a real EIO, and a caller
> _could_ if they chose do:
>
>   if (commit_lock_file(&lock)) {
> 	if (!errno)
> 		error("error writing to file");
> 	else
> 		error_errno("error closing file");
>   }

> But I am not sure I would want to annotate all such callers that way. It
> would probably be less bad to just pass down a "quiet" flag or a strbuf
> and have the low-level code fill it in. And that solves this problem
> _and_ the rename() thing above.
>
> But TBH, I am not sure if it is worth it. Nobody is complaining. This is
> just a thing we noticed. I think setting errno to EIO or to "0" is a
> strict improvement over what is there (where the errno is essentially
> random) and the complexity doesn't escape the function.
>
> So I think that "easy" thing falls far short of a solution, but it's at
> least easy. I could take it or leave it at this point.