The default version is pro. To get to another version,
from the unix prompt type:
stardev (e.g. for dev)
All the corresponding environment variables will then point to dev.
To see what command maps to what version look in $STAR_ROOT/packages.
Versions dev, new, pro etc. are links pointing to release directories
For example, it is currently:
dev --> 98f new --> 98d pro --> 98e frozen --> old --> 98b
To go to a particular release that doesn't have one of the above
release directories, type (e.g. for 98a)
To see what version you're set up to use, type 'which staf' or 'STAR_LEVELS'.