Forward space records on a DITTO device
Forward spaces a specified number of physical records on a DITTO device. The user has the option to forward space records on the input device or output device.
- DEVTYPE
- Device type. Specifies which input/output device is to be processed. Valid values are:
= INPUT: Input device. Process input DITTO device. = OUTPUT: Output device. Process output DITTO device.
- NRECS(0)
- Number of records. Specifies the number of physical records to be forward spaced on the input or output device.
The user has specified to forward space two physical records from the current position on the input device.
Before: file ptr. | v ------------------------------------------------ | | | | | |E| |record 1|record 2|record 3|record 4|record 5|O| | | | | | |F| ------------------------------------------------ After: file ptr. | v ------------------------------------------------ | | | | | |E| |record 1|record 2|record 3|record 4|record 5|O| | | | | | |F| ------------------------------------------------
The user has specified to forward space four physical records from the current position on the output device.
Before: file ptr. | v -------------------------------------------------- | | |E| | | |E| |record 1|record 2|O|record 1|record 2|record 3|O| | | |F| | | |F| -------------------------------------------------- After: file ptr. | v -------------------------------------------------- | | |E| | | |E| |record 1|record 2|O|record 1|record 2|record 3|O| | | |F| | | |F| --------------------------------------------------
The parameters are input into the program. From the parameter DEVTYPE, it is determined which device is to be processed. The specified number of physical records are forward spaced from the current position of the DITTO device.
file ptr | v -------------------------------- | |E|E| | |O|O| | |F|F| --------------------------------
file ptr | v ------------------------------ | |E| | |O| | |F| ------------------------------