The purpose of the CHECK option is to perform a dry run to inform you of possible errors, and to provide reports of SYSMOD status, libraries that will be updated, regression conditions, and SYSMODs that will be deleted. Target system libraries are not permanently updated.

During check processing, the list of target zone entries is maintained in storage; data is written to the target zone as a temporary storage medium. Check processing deletes any data written to the target zone. Consequently, no permanent updates are made to the target zone.