Two alphanumeric characters are appended to CUNUNI to form the name of the CUNUNIxx parmlib member. After initialization, you can issue the SET UNI command to change the CUNUNIxx member; however, this change is temporary. At the next IPL, the system uses the CUNUNIxx member specified in IEASYSxx. For information about IEASYSxx, see IEASYSxx (system parameter list). For descriptions of the SET command, see z/OS MVS System Commands.