Default Configuration

Each working environment specifies its own Default Configuration. When you open a SNiFF+ project in a working environment, SNiFF+ uses its Default Configuration:

- for setting the default value when you choose one of the various version control commands (e.g., check-out and check-in).
- when updating files in the working environment to the most current versions available in the Repository. A file is updated with respect to the Default Configuration in the file's version tree.

| Note
| SNiFF+ automatically sets the Default Configuration for a newly created working environment to HEAD . You can change this default behavior either while creating a new working environment or afterwards.

To better understand the idea of a Default Configuration, let's suppose you work on a software system with files having the same version tree we looked at on page 159:

You work on the main "trunk" of the tree and check out and check in files on the trunk. A member in your team works on the branch of the tree created at version

1.2 . As a result, the Default Configuration for your PWE would be HEAD , and the Default Configuration for your team member's PWE would be HEAD_branch .
IMPORTANT: Actually, in this example, your team member should specify two Default Configurations for his/her PWE. The next section discusses why.
Using multiple Default Configurations
Not all version controlled files in your Repository will have the same version tree. During normal development, files will often be created and checked into the Repository. Now, if the Default Configuration for your PWE is on a branch and you try to perform version control operations on a file that doesn't have this branch, your version control tool will complain.
To get around this problem, SNiFF+ allows you to specify multiple Default Configurations for a single working environment. If SNiFF+ can't perform a version control operation using the first specified Default Configuration, it will try to perform the operation using the next specified Default Configuration, and so on, until it is successful.
Going back to the example in the last section, your team member could specify two Default Configurations for his/her PWE. The first one would be HEAD_branch , and the second could be HEAD .

| Note
| To learn how to specify the Default Configuration(s) for a working environment, please refer to Specifying Default Configurations.