From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael Kerrisk (man-pages)" Subject: Re: For review: pidfd_open(2) manual page Date: Mon, 23 Sep 2019 22:57:40 +0200 Message-ID: References: <90399dee-53d8-a82c-3871-9ec8f94601ce@gmail.com> <87tv939td6.fsf@mid.deneb.enyo.de> <63566f1f-667d-50ca-ae85-784924d09af4@gmail.com> <874l12924w.fsf@mid.deneb.enyo.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <874l12924w.fsf@mid.deneb.enyo.de> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Florian Weimer Cc: mtk.manpages@gmail.com, Christian Brauner , Jann Horn , Daniel Colascione , "Eric W. Biederman" , Joel Fernandes , Linux API , lkml , linux-man , Oleg Nesterov List-Id: linux-api@vger.kernel.org Hello Florian, On 9/23/19 10:41 PM, Florian Weimer wrote: > * Michael Kerrisk: > >>>> static >>>> int pidfd_open(pid_t pid, unsigned int flags) >>>> { >>>> return syscall(__NR_pidfd_open, pid, flags); >>>> } >>> >>> Please call this function something else (not pidfd_open), so that the >>> example continues to work if glibc provides the system call wrapper. >> >> I figured that if the syscall does get added to glibc, then I would >> modify the example. In the meantime, this does seem the most natural >> way of doing things, since the example then uses the real syscall >> name as it would be used if there were a wrapper function. > > The problem is that programs do this as well, so they fail to build > once they are built on a newer glibc version. But isn't such a failure a good thing? I mean: it encourages people to rid their programs of uses of syscall(2). >> But, this leads to the question: what do you think the likelihood >> is that this system call will land in glibc? > > Quite likely. It's easy enough to document, there are no P&C issues, > and it doesn't need any new types. Okay. > pidfd_send_signal is slightly more difficult because we probably need > to add rt_sigqueueinfo first, for consistency. Okay. I see that's a little more problematic. Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/