 VDV - Virtual Device Utility

 VDV is used to connect to and disconnect from devices  on  other  systems
 (DECnet nodes) and manage a "virtual device" on the local system  through
 which I/O requests can be directed to the  remote  device.  VDV  supports
 operations to disks, printers, and tapes on remote systems which have the
 VDH host server task (object type 50.) installed. In addition,  the  user
 may connect to a file located on the remote system, and perform  disk I/O
 operation to that file. The virtual device allocated  appears  to  be  as
 large as the  number  of  blocks  in  the  file.  Once  a  connection  is
 established, the user can perform  all  I/O  operations  on  the  virtual
 device  which  are  supported  on  the  physical  device  (disks  can  be
 initialized, mounted, etc.). When the virtual device is disconnected,  it
 appears as offline to the operating system.

 Commands are:
	
	CONNECT		DISCONNECT

 For additional information type:

	>HELP VDV command

 This software is unsupported, although problems and suggestions can be
 reported to: Jeffrey Schriesheim (ELROND::SCHRIESHEIM)
	      TW/E07, 247-2259

2 CONNECT

   To CONNECT to a remote device or file  --

	>VDV CONNECT nodespec::target [NAME lognam] [GLOBAL]

	Where:
		nodespec::	= The node specifier as in NFT
				  (node/user-id/password/account::)
		target		= The target device or file to which the
				  connection is requested.
		lognam		= A optional logical device name to be
				  assigned to the virtual device
				  allocated if the connection is successful.
				  This name is of the standard RSX format
				  (dduu:)
		GLOBAL		= This keyword declares that the device
				  is to be allocated for all users, and
				  it will not be disconnected on user
				  log-off.

    The target name is passed to the remote system, where  it  is  parsed.
    If only a device name is specifed,  the  target  device  is  attached.
    For RSX-11M-Plus systems, the target device must  be  set  public  and
    mounted as foreign before it can be used. If a file name is specified,
    the target file will be opened. There can be optional switches on  the
    file name which affect  the  file  opening.  For  information  on  the 
    switches type:

	 >HELP VDV CONNECT SWITCHES

3 SWITCHES

   The following switches may be applied to filenames when using the CONNECT
   command:

	Switch			Effect
	------			------
	/RO			Applied to an existing file only, means
				open read-only (software write locked).
				Default = /-RO
	/CR			Create a new file.
	/BL:n			Used in conjunction with /CR to specify
				the number of blocks to be allocated when
				creating the file. Default = 4800 blocks.
	/CO			Used in conjunction with /CR to specify
				that the created file is to be contiguous.
				Default = /-CO
	/TM			Used in conjunction with /CR to specify
				that the file being created is a temporary
				file which will be deleted when the virtual
				device is disconnected.
				Default = /-TM

2 DISCONNECT

   To DISCONNECT from a remote device or file  --

	>VDV DISCONNECT virtual-device:

	Where:
		virtual-device	= The name of the virtual device
				  which has been allocated.

