Example

The following steps show how an installation can pass accounting parameters to the subsystem.

The SMF parmlib member used at SMF initialization contains:
```
   SUBPARM(ABCD(ONESETOFPARMS))
```
During the initialization of the ABCD subsystem, ABCD issues the SMFSUBP macro to retrieve the initial parameter information.
- During this point in the processing, the subsystem does whatever it is specified to do by checking the contents in the parameter area.
- It then continues with its initialization.
If the installation changes the value of the parameter, either by using the SET SMF=xx command to change parmlib members, or by using the SETSMF command as follows:
```
   SUBPARM(ABCD(ANOTHERSETOFPARMS))
```
to change the value for the SUBPARM, the result is that SMF issues the SMF SUBPARM Option Change call (SSI function code 58) to the ABCD subsystem to signal the change.
Subsystem ABCD could be any of the following:
- Undefined, which causes an SSI error
- Not enabled for the function code, which means no action
- Enabled for the function code, which invokes the subsystem's routine for the function code.
The function routine uses the SMFSUBP macro to retrieve the updated parameter information.
At this point in the processing, the subsystem processing depends on the contents of the parameter area, which will probably update controls for the subsystem.