D068 - 018-relational: properties instead of values, aimed where no document reaches

Status: decided, on external criticism, and the most useful thing to come out of it.

007-responsive compares two calls to each other rather than to an expected value. That is oracle-free testing, and it is the escape from having no hardware - but it was aimed at 54 libc and maths symbols, which is exactly where ISO C already supplies a free oracle and the technique is needed least.

The vendor surface has no oracle at all, and relations are still cheap there:

• two live event flags must not share a handle
• create and delete repeatedly must keep working - a leaking handle table fails
• memory released must be allocatable again at the same size
• a counting semaphore must refuse a third claim against two signals
• a thread asked twice for its identity must answer the same thing

None of these needs a struct layout or a documented error code, which is what makes them available now: BACKLOG §2 records struct-taking functions as blocked on layouts and §5 records the suite as leaning negative, and a relation routes around both rather than waiting on them.

They are spec rather than assumed. No document states these particular returns, but "two live objects do not share one handle" is not this project's opinion.

Validated on the host, which meant giving the host build small correct implementations of event flags and semaphores rather than constants. A check that has never passed a working implementation is not evidence, and constants would have left the whole section unexercised.