* Steven Rostedt (rostedt@xxxxxxxxxxx) wrote: > On Thu, 2012-01-12 at 10:39 -0500, Mathieu Desnoyers wrote: > > > pipe()/pipe2() > > dup()/dup2()/dup3() > > umount()/umount2() > > mmap()/mmap2() > > madvise()/madvise1() > > eventfd()/eventfd2() > > > > Those look very much like major version numbers to me. And these are > > entirely compatible with your statement above about using -ENOSYS to > > detect if the major version number is implemented or not. > > That's a stretch in calling version numbers. All but the madvise case > above are how many parameters it takes, not really a "version" number. > > It's adding a new syscall, not updating a version and then deprecating > the old one. As I believe all the above are still supported. > > > > > If your only concern is that the major version number should be part of > > the ABI name (as in the examples above), that can be arranged. > > > > > > > We've done this without version numbers. Just look at all the udev > > > changes. > > > > Are you seriously refering to udev as an example of how to handle > > changes, or as one of the worse ABI breakage mess that happened in the > > Linux kernel history ? My own experience as a Linux users (in the > > era around 2.6.12 kernels if my memory serves me right) lead me to think > > it's the latter. And because udev is part of the runtime support, that > > indeed led to non-bootable systems and lots of frustrated users. > > Yeah, I know it sucked, as I got burned by it too. But having "version" > numbers wouldn't have helped at all. In fact, it should have kept both > ways working much longer, or at least had the new udev support both. > > What udev did is more like what you want to do than what I did with > trace-cmd. OK. Then how can trace-cmd support the LTTng features ? Thanks, Mathieu -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
