On 2023-04-08 15:08, Paul Eggert wrote:

> the overlapping move constraint doesn't apply to the null 
> terminator.

Oh, sorry, scratch that: it does apply, because of the 'restrict' 
constraints on the argument pointers. Hence (contrary to my previous 
assertion) PATCH 1/2's code does conform to draft POSIX.

However, it's still worrisome that PATCH 1/2's behavior disagrees with 
OpenBSD's for some nonconforming calls. If the main point of the patch 
is compatibility, surely it is better to be compatible with existing 
practice, not merely with draft POSIX.

Anyway, please ignore the documentation patch I sent yesterday in this 
thread, and look instead at the attached. This is the same patch, except 
with fixed wording under strlcpy and strlcat as to whether behavior is 
undefined.