Duplicate files/job variables

During a SAVE or EXPORT run, the files or job variables may come both from an input tape and from a disk.

The DUPLICATE operand, which may be specified in the SAVE and EXPORT statements, supports files/job variables which exist on both tape and disk, in order to obtain a precise status of the file. The first file/job variable referred to in the FILES/JOBVAR statement is processed.

By specifying DUPLICATE=NO, it is possible to ensure that files/job variables are processed only once, and are thus saved/exported only once. A directory file is necessary for the save or export run in this case.

Checking for duplicate files increases the runtime of ARCHIVE.