DITTO -- Mapper Routine
Produces a summary of the files, records, and record lengths on the specified device. If the mapper command is run on a magnetic tape, the tape is rewound before processing begins and rewound to the beginning of tape at completion. If the mapper command is run on a disk file, processing begins at the beginning of the file; after completion, the file pointer is returned to beginning of file.
- DEVTYPE
- Device type. Specifies which input/output device is to be processed. Valid values are:
= INPUT: Input device = OUTPUT: Output device
- PRINT(TERM)
- Output destination. The destination of the output.
= TERM: Terminal. Output is sent to the user's terminal. = LP: Line printer. Output is sent to the printer defined by $PRINTER. = Filename: User-supplied filename. Output is sent to the user-supplied file with the extension ".prt".
The user has requested to do a mapper on the input device. If the input device is tape, the tape is first rewound. The generated output is written to the terminal.
From input parameter DEVTYPE, it is determined on which device the mapper is to be run. If the device is tape, the tape is rewound before processing begins. The generated output is written to the appropriate destination as specified in parameter PRINT.