  Do Linux distribution package managers need the privileged operations they
request to actually happen? Apparently not, at least for building container
images for HPC applications. We use this observation to implement a root
emulation mode using a Linux seccomp filter that intercepts some privileged
system calls, does nothing, and returns success to the calling program. This
approach provides no consistency whatsoever but appears sufficient to build all
Dockerfiles we examined, simplifying fully-unprivileged workflows needed for
HPC application containers.
