Based on the decisions you have made about how to manage duplicate or undefined volume serial numbers, tailor the supplied sample EDGUX100 exit module as follows:

1. Make a copy of the sample exit module to use as a base for your exit module.
2. Update the exit module. Only perform your processing when the PL100_CAN_IGNORE bit is set to B'1'. Decide whether to support the pre-ACS call to obtain a VRS management value or scratch pool prefix for use as the MSPOLICY and MSPOOL variables in ACS processing. You must ignore the call if the volume is to be ignored. During the pre-ACS call, an ACERO is passed instead of a JFCB. See z/OS DFSMS Installation Exits for information about the ACERO. See Assigning expiration dates for additional processing information.
   • Use the value in the JFCB expiration date field, JFCBXPDT, to determine if a special date has been specified. You could also use the PL100_ACCODE field to check if the special ACCODE value has been supplied.
   • Set one of these flags to B'1' so that the volume is ignored if the special date 98000 or the special ACCODE=xCANORES value has been specified. The flags are
     • PL100_SET_IGNORE
     • PL100_SET_IGNORE_MOUNTED
     • PL100_SET_IGNORE_REQUESTED
   • Set PL100_SET_NOTBYPASS_SAFRC8 bit to B'1' to turn off the function that uses the successful IGNORE authorization to change SAF return code 8 (not authorized) to 0. The flag is evaluated only in conjunction with PL100_SET_IGNORE, PL100_SET_IGNORE_MOUNTED, and PL100_SET_IGNORE_REQUESTED.
   • Update the WTO messages with a rack number. Place the rack number value in the PL100_RACKNO field
   • Clear the expiration date in the JFCB copy that DFSMSrmm uses to prevent DFSMSrmm from using the 98000 date as a volume expiration date. You do not need to update the JFCB. The information is not passed on to DFSMSrmm. Because it is a copy of the JFCB used solely by DFSMSrmm, no other component can make use of your changes. However, because the EDG_EXIT100 installation exit is called for system-managed volumes, but nonspecific system-managed volumes cannot be ignored, the DFSMSrmm sample exit module clears the expiration date.