IBM Rational ClearCase is a version control, workspace management, parallel development support, and build automation solution developed by IBM. The ClearCase client plugin is available on Linux and Windows for accessing a ClearCase server.

Using GNU Diffutils with ClearCase

You can use the GNU Diffutils tool With ClearCase to compare files and activities:

1. Download Diffutils and extract it to a directory in your PATH.
2. Select Tools > Options > Version Control > ClearCase.
3. Select the External radio button. The radio button is disabled if diff is not found in the PATH.
4. In the Arguments field, specify arguments for running diff.

Checking out and Checking in

In addition to the standard version control system functions described in Using Common Functions, you can check out and check in files.

To create a writable copy of a file, select Tools > ClearCase > Check Out. If you check out files in a Unified Change Management (UCM) view, they are added to the change set of a UCM activity. By default, the activities are automatically assigned names. To disable this functionality, select Tools > Options > Version Control > ClearCase, and then deselect the Automatically assign activity names check box.

To automatically check out files when you edit them, select Tools > Options > Version Control > ClearCase, and then select the Automatically check out files on edit check box.

To cancel the checkout for a file and delete the checked-out version, select Tools > ClearCase > Undo Check Out.

To check in checked-out versions of files in the change set of the current UCM activity, select Tools > ClearCase > Check In Activity.

To create a permanent new version of the current file or all files in the versioned object base (VOB), select Tools > ClearCase > Check In. To be asked to confirm that you want to check in the files, select Tools > Options > Version Control > ClearCase, and then select the Prompt on check-in check box.

By default, you are asked to enter a comment when checking files out or in. To suppress this prompt, select Tools > Options > Version Control > ClearCase, and then select the Do not prompt for comment during checkout or check-in check box.

If you change the read-only attribute of a file that is loaded into a snapshot view and modify the file without checking it out, you hijack the file. To revert a hijacked file to its checked in version, select Tools > ClearCase > Undo Hijack.

By default, the files in the VOBs are indexed for quick access to their statuses. To disable indexing, select Tools > Options > Version Control > ClearCase, and then select the Disable indexer check box. To only have some VOBs indexed, specify them in the Index only VOBs field.