The name of the file is generated by a Master Agent. It is created during the diet_initialize() call. The name of the file is the aggregation of the string ID_FILE plus the name of the MA plus the number of the session.
A file is created only when there are some persistent data in the session.
For example, ID_FILE.MA1.1 means the identifiers of the persistent data stored are in the file corresponding to the first session in the Master Agent MA1.
The file is stored in the /tmp directory.