The resolver currently invokes the backend open path before returning AlreadyExists for an existing O_CREAT|O_EXCL target. Backend-specific errors or side effects such as truncation can therefore occur before the exclusive-create result. Confirm the intended error precedence with the original fs author, then reject exclusive creation before backend open and add combined O_EXCL/O_TRUNC coverage. Deferred from #1318.
The resolver currently invokes the backend open path before returning AlreadyExists for an existing O_CREAT|O_EXCL target. Backend-specific errors or side effects such as truncation can therefore occur before the exclusive-create result. Confirm the intended error precedence with the original fs author, then reject exclusive creation before backend open and add combined O_EXCL/O_TRUNC coverage. Deferred from #1318.