A special command is a privileged operator command whose format and function are defined by systems support.
Any special command received is passed by the system to an authorized user program which interprets the command and performs the desired actions. The processing of special commands is thus a special application of authorized user programs.
The following applies:
An operation code (= name) must be defined for each special command. This operation code must not coincide with the operation codes of ordinary operator commands. For example, the operation code “CANCEL” is not permitted as an operation code for a special command.
Every special command has to be assigned to a functional area, i.e. the command is given a routing code. If a special command cannot be linked to any of the existing functional areas, it must be assigned one of the private areas (routing codes W, X, Y, Z).
In order to enable a special command to be input from a user task with the OPERATING privilege, it must be defined in an SDF syntax file with SDF-A. This syntax file must precede the user task. ADD-CMD ...,IMPLEMENTOR=APPLICATION defines that the command processing is executed in an authorized user program.
From the point of view of the user, an important factor for the behavior of special operator commands is whether the commands have the manageability attribute. A distinction is made between manageable and non-manageable special operator commands.
Manageable special commands
These are managed by the system in just the same way as normal operator commands. It is possible to exchange command-linked messages. The command termination message is - except in error situations - prompted by the command execution $CONSOLE application and includes an evaluable return code.
Non-manageable special commands
These are regarded by the system as “terminated” as soon as they have successfully been sent (with DCAM) to the command execution $CONSOLE application. It is not otherwise possible to exchange command-linked messages. If the operator uses a nonadministerable special command, he will receive the following message
NBR0740 COMMAND TERMINATED '<cmd-name>':
RESULT: (SC=00, SC1=00,MC=NBR0768); DATE:<date>
However, this only means that the command was passed to the relevant server. The final result of the command is not included in a termination command and command job IDs are not found as message job IDs in the command results.
Command | Meaning |
CONNECT-CMD-SERVER | Create link between authorized applications and operator commands |
DISCONNECT-CMD-SERVER | Delete link between authorized application and operator command |
SHOW-CMD-ATTRIBUTES | Output information on operator commands |
Table 47: Command overview of special operator commands