[Users] entering a VE

[Kir Kolyshkin]

Marco d'Itri wrote:
> Can somebody explain the exact roles of setluid() and of the
> VZCTL_ENV_CREATE ioctl or point me to documentation?
>   
setluid() is to put the caller inside a proper beancounter. This is 
needed so all the resource controls will be enforced.

VZCTL_ENV_CREATE is used to enter a VE, or test if VE is running. I 
assume the best docs available is the OpenVZ kernel source code.
> I am trying to write a replacement of "vzctl enter", but my ultimate
> goal is to write a PAM module which can be used by cron/ssh/etc running
> in the HN to switch to the VE context. The code will be GPL'ed.
> (If anybody believes that this cannot work then it is the right time to
> say it...)
>
> I also do not understand well the issues related to open file
> descriptors: why does vzctl use pipes between the two processes for
> stdin/out/err?
> Will anything change if stdin/out/err are connected to sockets instead
> of ttys?
>
>