Messages in this thread | | | Date | Tue, 26 Jul 2016 12:11:02 -0700 | From | Andrew Vagin <> | Subject | Re: [PATCH 0/5 RFC] Add an interface to discover relationships between namespaces |
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On Tue, Jul 26, 2016 at 11:32:25AM -0700, W. Trevor King wrote: > On Tue, Jul 26, 2016 at 11:25:24AM -0700, Andrew Vagin wrote: > > Sure. If a process wants to compare two namespaces, it needs to get file > > descriptors for them (open /proc/PID/ns/XXX, use new ioctl-s, find a > > process which has them), > > and then it calls kcmp(pid1, pid2, KCMP_NSFD, ns_fd1, ns_fd2) > > If you use the new ioctl-s to get ns_fd2, do you walk your local /proc > to find pid2?
If you use the new ioctl-s to get nf_fd2, you will have it in the current process, so pid2 will be getpid().
pidX identifies a process where to find fdX.
man 2 kcmp: The kcmp() system call can be used to check whether the two processes identified by pid1 and pid2 share a kernel resource such as virtual memory, file descriptors, and so on.
> > Cheers, > Trevor > > -- > This email may be signed or encrypted with GnuPG (http://www.gnupg.org). > For more information, see http://en.wikipedia.org/wiki/Pretty_Good_Privacy
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