--On Sunday, February 14, 2021 1:52 PM -0500 H <agents at meddatainc.com> wrote: > Apart from what you described above, is it in general possible to force a > non-shell user to use a specific version of software when multiple > versions are installed on a machine, be it php, python or something else? As I said, use the path. The path environment variable isn't part of a shell, but shells provide nice ways to manipulate it. The scripts provided with Software Collections modify the path and possibly other variables before invoking a shell or a program. Environment variables are part of a process' state and are inherited when a process spawns a child. A shell is just a special kind of process that provides interactive support and may provide a programming API.