forest raptor
I would like to inspect a container to find the number of available CPUs so that I can generate the right build commands. It looked like I should be able to read "/proc/cpuinfo" from the container, but this fails with an error
container.from.file lstat /tmp/buildkit-mount707493033/proc/cpuinfo: no such file or directory
I think I can work around this using Exec, but it's a bit of a surprising error to me ...
onyx moth
That’s because /proc is a virtual filesystem that only exists in memory for processes running inside the container where it’s mounted
So it’s actually expected behavior that you need an exec for this
forest raptor
So it's not there because .File doesn't have a mount namespace for procfs?
FWIW, an exec with a redirect works fine.
karmic hull
So it's not there because `.File` doesn't have a mount namespace for procfs?
yes, that's correct. File accesses the container layered filesystem directly where /procfs doesn't exist since it's only mounted when a process effectively runs