Hi Ahmed, On Fri, Sep 20, 2019 at 03:46:09PM +0200, Ahmed S. Darwish wrote: > Problem is, glibc is still *really* slow in adopting linux syscall > wrappers, so I'm not optimistic about that... > > I still see the new system call as the sanest path, even provided > the cost of a new syscall number.. New syscalls are always a pain to deal with in userland, because when they are introduced, everyone wants them long before they're available in glibc. So userland has to define NR_xxx for each supported arch and to perform the call itself. With flags adoption is instantaneous. Just #ifndef/#define, check if the flag is supported and that's done. The only valid reason for a new syscall is when the API changes (e.g. one extra arg, a la accept4()), which doesn't seem to be the case here. Otherwise please by all means avoid this in general. Thanks, Willy