Messages in this thread | | | Date | Thu, 13 Jul 2006 02:09:50 -0400 | From | "Albert Cahalan" <> | Subject | Re: [PATCH] Use uname not sysctl to get the kernel revision |
| |
On 7/13/06, H. Peter Anvin <hpa@zytor.com> wrote: > Albert Cahalan wrote: > >> > >> The numerical namespace for sysctl is unsalvagable imho. e.g. > >> distributions regularly break it because there is no central > >> repository of numbers so it's not very usable anyways in practice. > > > > Huh? How exactly is this different from system call numbers, > > ioctl numbers, fcntl numbers, ptrace command numbers, and every > > other part of the Linux ABI? > > > > Mostly because some branches of the sysctl tree have dynamic content > which is hard to marshal into a numeric form.
Dynamic content is no problem. FreeBSD uses sysctl to implement their "ps" program. The process info comes out of sysctl now. The sysctl man page has an example.
Non-numeric data is more troublesome. FreeBSD has a syscall that will take text (still faster than /proc/sys), and another that will convert the text representation into numeric form for later high-performance use.
Look up all 3 calls here, in section 2: http://www.freebsd.org/cgi/man.cgi?manpath=FreeBSD+7.0-current - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |