Re: [libvirt] lxc: setsid() usage

Am 22.06.2015 um 16:51 schrieb Daniel P. Berrange: > On Mon, Jun 22, 2015 at 04:40:37PM +0200, Richard Weinberger wrote: >> Hi! >> >> Why is libvirt-lxc issuing a setsid() in lxcContainerSetupFDs()? >> To me it seems like a hack to have a controlling TTY if PID 1 is /bin/bash. > > I honestly can't remember the reason. It might have been to ensure we have > separation from the libvirt_lxc session. Hm, can be. >> If one runs a sysv init style distro (like Debian) in libvirt-lxc the setsid() has >> a major downside, when getty spawns a login shell on /dev/tty1 it cannot become >> the controlling tty. Hence, if one presses ctrl-c in such a session, the container will >> reboot. > > Is that problem due to the fact we call setsid(), or due to use calling > ioctl(TIOCSCTTY) ? If I remove the TIOCSCTTY nothing changes. Without setsid() libvirt is unable to start the container at all. So, I fear you're right that it has something do to with the libvirt session.