My base ClearCase config spec reads like this:
element * CHECKEDOUT
element * .../Branch_F13R2/LATEST
All is good, but I am wondering what is the .../ doing at the beginning of the path? In UCM, we can see the streams and VOBS in Clear Case explorer, but in base ClearCase, how to know that if I want to check out from Branch_F13R2, I need .../ at the beginning?
That is because you don't know the parent branch.
.../ in a selection rule allows for ClearCase to select that branch, from whatever branch it comes from: /main, or any other branch.
To see more about that notation, called ellipsis wildcard, see "Find all files modified in a specific ClearCase branch?".
I would also recommend to add the rule
element * /main/LATEST
Not every parent directory has a version in the branch you are looking for, and without this last selection rule, it would have nothing to select, making any sub element inaccessible.
来源：https://stackoverflow.com/questions/14448882/details-of-config-spec-in-base-clearcase