 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.
