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Re: PATCH: Add x32 dummy sysctl
"H.J. Lu" <email@example.com> writes:
> On Thu, May 17, 2012 at 1:09 PM, Roland McGrath <firstname.lastname@example.org> wrote:
>>> X32 doesn't have _sysctl system call. ÂThis patch adds a dummy. ÂOK
>>> to install?
>> Then you shouldn't install <sys/sysctl.h> either. ÂSince these are added to
>> sysdep_routines and sysdep_headers in sysdeps/unix/sysv/linux/Makefile and
>> a linux/x32-specific Makefile would be before it, I think what you need to
>> do is set some variable in linux/x32/Makefile to say there's no sysctl and
>> then have linux/Makefile check that.
>> That's hacky, but it's better than moving the settings into copies
>> in every other linux/<machine>/Makefile.
>> Alternatively and arguably cleaner though a little less obvious:
>> move those additions from linux/Makefile into linux/sysctl.mk
>> and give linux/Makefile:
>> include $(firstword $(wildcard $(sysdirs:=/sysctl.mk)))
>> Then you can add a linux/x32/sysctl.mk to override linux/sysctl.mk
>> with a dummy.
>> I like the latter one better. ÂIt certainly needs thorough comments.
> How about adding a _sysctl to return -1 and set errno to ENOSYS?
Isn't failure to build better for a system call that has never been nor
will ever be supported on an architecture?
At least on linux sysctl as a separate system call is dead. We are just
gradually taking our time removing old cruft.