A user syntax file may be activated, but need not be. For a task started under the identification <userid>, the user syntax file cataloged under the name $<userid>.SDF.USER.SYNTAX is automatically activated following processing of the SET-LOGON-PARAMETERS command.
During a task the user may activate/deactivate one or more user syntax files with the MODIFY-SDF-OPTIONS command. A user syntax file may contain extensions, limitations and other modifications relative both to the system syntax files and, in certain cases, to the group syntax file. Possible extensions and other functional modifications are restricted to program statements and to commands which are implemented via procedures. Limitations on functional scope defined in a system or group syntax file for BS2000 commands (implemented via system modules) cannot be lifted in a user syntax file.
User syntax files must be generated by the user with the aid of the software product SDF-A, but can also be supplied with certain software products.
If new or modified commands or statements are delivered with a new product version, then all user syntax files that contain this command or statement definition must be replaced or modified accordingly.