No, it couldn't introduce such a macro, because such would have to assume all d_name entries are the same length. Adding an option to the interface to do a count, as a vararg parameter, and directly malloc the necessary space, returned via my suggested change to buf as a **, is plausible. Since we are merging common behaviors with this interface introduction, not describing a single reference implementation, such changes are permitted if someone commits to doing an implementation, afaik. On Tuesday, September 1, 2020 Steffen Nurpmeso via austin-group-l at The Open Group <stef...@sdaoden.eu> wrote: Geoff Clare via austin-group-l at The Open Group wrote in <20200901143300.GB24606@localhost>: |> ---------------------------------------------------------------------- |> (0004953) philip-guenther (reporter) - 2020-08-28 22:52 |> https://www.austingroupbugs.net/view.php?id=697#c4953 |> ---------------------------------------------------------------------- |> I think the unspecified nature of the d_name member in the new posix_dent |> makes writing portable software more difficult while providing only \ |> minimal |> benefit to programs that don't care. I would support requiring it \ |> to be a |> flexible array member and thus eliminating the error of declaring \ |> an array |> and trying to walk it via indexing instead of by advancing a char pointer |> by d_reclen. | |I think we should keep the requirements for d_name the same between |struct dirent and struct posix_dent. Some implementations of |getdents() and getdirentries() use struct dirent and they should be |able to make posix_getdents() a synonym (or a light wrapper) for the |existing function by making struct posix_dent be identical to struct |dirent. We can't require d_name in struct dirent to be a VLA since |there are implementations where it is not.
The standard could also introduce a macro which could be used to space a buffer accordingly, something like (very ugly) POSIX_GETDENTS_BYTES_FOR_DENTS(number-of-desired-dents), and use it in the example. Like that any possible errors with buffer space allocation would not even be introduced (except for possible integer overflows, maybe). --steffen | |Der Kragenbaer, The moon bear, |der holt sich munter he cheerfully and one by one |einen nach dem anderen runter wa.ks himself off |(By Robert Gernhardt)
