Note Please read the common steps first. Note udocker is not Docker. udocker provides four modes for running containers as a non-root user: Pn: Proot mode Fn: fakechroot mode Rn: rootless runc mode Sn: Singularity (now called Apptainer) mode The third mode (Rn) falls into the scope of Rootless Containers, and the fourth mode (Sn) also does when it runs in non-setuid mode, but the others do not: Pn and Fn are not containers (in our view).
