The magnetic tape handling options LEAVE and REREAD allow you to specify the action to be taken when the end of a magnetic tape volume is reached, or when a data set on a magnetic tape volume is closed. The LEAVE option prevents the tape from being rewound. The REREAD option rewinds the tape to allow reprocessing of the data set. If you do not specify either of these, the action at end-of-volume or on closing of a data set is controlled by the DISP parameter of the associated DD statement.
>>-+-LEAVE--+-------------------------------------------------->< '-REREAD-'
If a data set is first read or written forward and then read backward in the same program, specify the LEAVE option to prevent rewinding when the file is closed (or, with a multivolume data set, when volume switching occurs).
The effects of the LEAVE and REREAD options are summarized in Table 18.
|
ENVIRONMENT option |
DISP parameter |
Action |
|---|---|---|
| REREAD | -- | Positions the current volume to reprocess the data set. |
| LEAVE | -- | Positions the current volume at the logical end of the data set. |
|
Neither REREAD nor LEAVE |
PASS DELETE KEEP, CATLG, UNCATLG |
Positions the volume at the end of the data set. Rewinds the current volume. Rewinds and unloads the current volume. |