The Disk Save and Compress (DSC) utility program copies Files-11 disk volumes to tape or disk for backup and storage. When it is used for volume restoration, it reallocates and consolidates the resulting disk. The general form of the DSC command line is: outdev(s):[outlabel][/outswitches]=indev(s):[inlabel][/inswitches] where: outdev: lists output device(s) to which data is transferred. The format of outdev: is ddn, where dd is the two letter ASCII device name and n is the octal unit number. When more than one tape drive is listed, the device symbols must appear in succession, separated by commas, before any other command parameters are specified. E. G., DSC>MM0:,MM1:SYSFILE=DB1: outlabel If the output device is a disk, outlabel is the new disk label. If outlabel is omitted, the label of the disk will be the same as that of the original input disk. If the output device(s) is a magtape, outlabel is the file name of the disk image on the tape. outswitches One or more of the following optional switches: /AP, /BAD, /BL, /CMP, /DENS, /RW, /VE For more information, type HELP DSC switch indev lists the inputs device(s) in the same format as outdev inlabel The identifier of the DSC-created magtape file that is to be transferred to disk. If a file label was not provided when a disk is created from a tape, the first file on the tape is transferred. inswitches One or more of the following optional switches: /BL Specifies output blocking factor /RW Rewinds magtapes before execution of the command 2 AP The /AP switch causes DSC to append a copy of the input device to the specified output magtape. /AP is valid only if that tape is the only tape of the tape set. The copy may not extend to succeeding magtapes. 2 BAD There are three forms of the DSC switch /BAD. They are: /BAD=MAN Causes DSC to prompt for bad blocks to be added to the output volume's bad block file, [0,0]BADBLK.SYS /BAD=MAN:NOAUTO Combination of /BAD=MAN and /BAD=NOAUTO /BAD=NOAUTO Causes DSC to ignore the bad block descriptor area on the disk. The bad block file will be empty unless bad blocks are entered manually. 2 BL The blocking factor switch has the form of: /BL=n where n is the number of disk blocks that should be written at one time. The default is n=4, and 4 is the smallest value that should be specified. Specifying a large value for n decreases the amount of time necessary for the copy by reducing the number of required I/O commands. Once a blocking factor is specified, it becomes the default blocking factor until a new value is specified or until DSC exits. If magtape is specified as the input device, the blocking factor is automatically set to the value at which that tape was created. DSC will expand its partition to honor large values of n. It will not attempt to shrink its partition. 2 CMP The /CMP switch causes DSC to compare the input and output volumes without first performing a copy operation. The input and output volumes cannot both be magtapes. Multireel magtapes can be compared with a disk. When the compare of the current tape is completed, the operation will continue on the next volume until all reels have been compared. 2 DENS The DSC density switch for magtapes has the following format: /DENS=1600 Specifies that the output magtape be written at 1600 bpi. It is not necessary to use this switch on input magtapes. /DENS=800:1600 The switch is not valid on a TM03 magtape controller. It specifies that the first two blocks on every output tape be written at 800 bpi. The remainder of the magtape will be written at 1600 bpi. 2 RW The /RW switch specifies to DSC that all magtapes be rewound before they are used. 2 VE The /VE switch specifies to DSC that it should do a compare operation between the input and output volumes after the input volume is copied to the output volume. The input and output volumes cannot both be magtapes.