Using NUCEXT to Create Immediate Commands

The IMMCMD parameter of the NUCEXT macro defines a nucleus extension as an immediate command. Using NUCEXT to define immediate commands has several advantages:
  • Nucleus extensions can be created in free storage.
  • Nucleus extensions can survive abend processing and end-of-command processing.
  • Nucleus extensions can be invoked as exits during abend (SERVICE parameter) and end-of-command (ENDCMD parameter) processing.

Nucleus extensions established as immediate commands can be invoked explicitly (enter the command at the terminal or from an exec) or as part of normal CMSCALL or SVC 202 processing. See Nucleus Extensions for details.