The following summarizes HZSPRMxx characteristics:

Default member supplied by IBM®?

No

Required or optional?

Optional

Directly affects performance?

No

Read at IPL or at command?

S hzsproc or F hzsproc command.

Allows listing of parameters at IPL or command?

Yes through F hzsproc,DISPLAY command

Response to errors:

Syntax error

Error message is issued

Read errors

Error message is issued

Unsupported parameters

Error message is issued

Support for system symbols?

Yes. See What are system symbols? in z/OS MVS Initialization and Tuning Reference.

Support for concatenated parmlib?

Yes