On 11/13/2013 11:16 AM, Rich Felker wrote:
We are not using clone() in a manner that is strictly equivalent to fork(). Libvirt is using clone() to create Linux containers with new namespaces. eg we do
clone(CLONE_NEWPID|CLONE_NEWNS|CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWUSER|CLONE_NEWNET|SIGCHLD)
Understood. I still call this a fork-like manner since it's not sharing VM or using CLONE_THREAD and using the default signal of SIGCHLD. BTW is there a reason to prefer this usage over regular fork followed by unshare()?
Yes. Per 'man 2 unshare', CLONE_NEWPID is not supported with unshare(), yet we require our child to have pid 1 in its new pid namespace. -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org