Command to delete branches of Clearcase element with "0" versions - clearcase

Question

What is the command in Clearcase to delete the branches of an element in which it is not modified (Element's version in that branch is "0") ?

Answer 1

You can simply remove the version 0 of that element (that I detail here).
That will remove the associated branch.
cleartool rmver file##/main/aBranch/0
You would need to "cleartool find" all elements with a version 0 (and no version 1), and rmver those version 0.
For a given branch, this would return all the versions to delete:
cleartool find -type f -version "version(.../blah/LATEST)&&version(.../blah/0)" -print
You can combine that with an exec directive:
# on Windows:
cleartool find ... -exec "cleartool rmver --force \"%CLEARCASE_XPN%\"
# on Unix:
cleartool find ... -exec 'cleartool rmver --force "$CLEARCASE_XPN\"'
Be careful with rmver, this is a destructive operation, so do test that carefully before executing the full find -exec rmver command!
Another approach is mentioned in "Purging Zero-Version-Only Elements in ClearCase" article, by George F. Frazier:
you need to purge your view of those troublesome entities.
Run the following command to find all zero-version elements:
cleartool find -avobs -branch'{
brtype(mybranch)&&!
(version(.../mybranch/1))}'
-print > c:\files.txt
This will find all elements with no version 1 on mybranch (if you read closely you'll notice it doesn't do the right thing if you have removed the 1 version of an element that already has versions greater than or equal to 2 — this is a rare situation though).
Once finished, it's simply a matter of using rmbranch to nuke the elements (make sure you know what you're doing here!).
There are many ways to do that; since I run the MKS toolkit, I execute the following from a command window:
cleartool rmbranch -f 'cat c:\files.txt'
Tamir suggests a trigger to automatically remove version 0, as listed in the IBM Rational ClearCase: The ten best triggers, under the section Empty Branch.
cleartool mktrtype -c "Automatically remove empty branch" -element -all -postop uncheckout -execwin "ccperl \\mw-ddiebolt\triggers\test_empty_branch.bat" REMOVE_EMPTY_BRANCH
That is good for future cases where an undo checkout leaves a version 0.

Answer 2

rmver won't work.
/home/ccadmin $ cleartool rmver -force ./VaREngine/Makefile##/main/nz_mig/nz_relOne/0
cleartool: Error: Cannot delete version zero without deleting branch: "./VaREngine/Makefile".