Packs are always stored inside the directory HOMEPACK. But a working pack can possibly be stored inside ROOTPACK if these two
directories are different. To do that one should temporarily set in the environment ROOTPACK=HOMEPACK ; the user is then considered
as an administrator of packs.
To alter ROOTPACK in that way, one should use the commands berootpack and behomepack preceeded with a ''dot''
(see the previous section).