This configures the way the snapshot is named, allowing the use of environment variables using the same syntax as Ant uses for property expansion.
i.e. a literal $ must be escaped as $$, and ${name} resolves to the value of environment variable "name".
If not set, the snapshot name defaults to "jobName_buildNumber".

The default is "${JOB_NAME}_${BUILD_NUMBER}". It can be set to any combination of literal text and environment variables, subject to AccuRev's snapshot naming restrictions: "The name must begin with a non-digit other than dot (.), and must not include either a slash (/) or a backslash (\)".
e.g. "${ACCUREV_STREAM}_${BUILD_NUMBER}_Snapshot" would take the name of the stream being built, append an underscore, append the build number and finally append "_Snapshot", which would result in a snapshot name of the form "MyStreamName_1234_Snapshot".