Additional information available:

DISK

   The MODIFY DISK command will allow the VMS file size of an existing
   virtual  disk  file to be increased up to the MS-DOS formatted size
   specified when the disk was created.

   Format:

     MODIFY DISK filespec

Additional information available:

ParametersQualifiers

filespec

   filespec is a standard VMS file  specification,  and  is  the  file
   specification by which the virtual disk file is known.  The default
   file extension for a virtual disk is ".DSK".  The target  directory
   for  the virtual disk file may be explicitly stated in the filespec
   or a standard location may be chosen.  In the later case, the /TYPE
   qualifier is used to select a target directory.

Additional information available:

/EXTENSION/TYPE

 /EXTENSION[=n]

   Specifies the number of blocks by which to extend the virtual  disk
   file.   If  n  is not specified, the file will be extended to match
   the currently formatted size of the virtual disk.  The disk may not
   be extended beyond its formatted size.

 /TYPE=class

   Determines  a  standard  target  directory  specification  for  the
   virtual  disk  file.   The  qualifier  selects  one of the logicals
   listed below based on the value of class.  The logical is  used  to
   provide   a  default  device  and  directory  when  generating  the
   filespec.  Possible values for the qualifier are:

   APPLICATION

                   The file will be placed in the directory determined
                   by the logical LAD$APPLICATION_DISKS.

   BOOT

                   The file is located in the directory determined  by
                   the logical LAD$BOOT_DISKS.

   SYSTEM

                   The file is located in the directory determined  by
                   the logical LAD$SYSTEM_DISKS.

   USER (default)

                   The  file  is  located  in  the   current   default
                   directory.