Directory Program Loading the DMKDIR object deck via the card reader is the same as
issuing the DIRECT command in CMS, except that after IPL, the program
asks you for the address of a card reader containing the Directory
program control Once the directory is updated, directory changes for a user currently
logged on to the system do not take effect until the user logs off the
system and then logs back on. When a new directory is written for a new system
the new directory does not take effect until the new
volume is loaded (via IPL). INVOKING THE DIRECTORY PROGRAM (DMKDIR) UNDER CMS residence volume,
system residence The iM/370 Directory vI virtual machine in the VM/370 directory. Each virtual machine
confiquration includes counterparts of the components found in a real System/370: a virtual operator's console, virtual storage, and virtual I/O devices and control units.
The same version of the Directory service program deck can be placed
in the card reader and loaded directly, or run in a virtual machine
under CMS. The CMS file named DIRECT can be updated with the CMS Editor to
incluae additional directory entries. Use the CMS DIRECT command to process any file to see if it follows the
required directory format. To actually change or swap the currently
active VM/370 directory, you must have both of the following:
1. User class A, B, or C.
2. write access to the system-owned (system residence or IPL device)
volume that contains the current directory up to and including the
directory cylinders, or to the volume that is to contain the new
directory.
If you have the above qualifications and wish verify that a CMS file can be used as a directory file, you must use the EDIT option;
otherwise, if there are no control statement errors, the file is put
into active use.
To build a VM/370 directory on a CP-owned volume using preallocated
cylinders, a new directory should be built so as not to overlay an
existing directory. You must, therefore, allow space for two
directories, or allocate a new area for the VM/370 directory each time
it is created. 1°8 IBM VM/370 Planning and System Generation Guide

Directory Program
If you execute the Directory program under VM/370, the newly created
directory is dynamically swapped, and placed in use by VM/370 (provided
that you have class A, B, or C and that the directory you updated is the
one that is currently in use by the system). If you do not have the
proper privilege class, the directory is updated on the directory volume
but not dynamically swapped, so the change will not go into effect until
the next time the system is loaded (via IPL). The format of the DIRECT
command is:
r , , t , L
DIRECT
r ,filename L
r Ifiletype IQIRECT L
r ", I filemode I I I I * III L ...... [ (EDIT) ]
filename [filetype [filemode]]
(EDIT)
is the identification of the file containing the control
statements for the Directory program. If no filename and
filetype are given, the program defaults to a file named USER DIRECT; otherwise, it looks for the file named. The filetype
must be DIRECT. If only filename is given, filetype defaults
to DIRECT. The filemode defaults to * if not specified.
specifies that the directory is to be examined, but not
changed. Under eMS, the DIRECT command loads the directory creation module.
The first statement encountered must be a DIRECTORY statement. If not
found, or another DIRECTORY statement is found, the program terminates. A syntax error in any statement generates an error message, and the
directory is not updated. If no critical errors are encountered, the
remaining statements are checked for syntax.
If the Directory program abnormally terminates, the old directory is
not altered. Normal completion places the directory in use by VM/370. After the new directory is created, it can be printed by issuing the CMS command PRINT USER DIRECT or PRINT filename DIRECT.
The DIRECT command filename and filetype default to a CMS file
identification of USER DIRECT. The filemode defaults to * if not
specified. Any or all of the defaults can be overridden by the command
line. The EDIT option allows you to run the program without updating
the directory on disk. This enables you to check the syntax of the
directory statements without accessing the directory disk. INVOKING DIRECTORY AS A STANDALONE PROGRAM Standalone operation in a virtual machine is the same as eMS operation,
with this exception: after IPL, the program asks you for the virtual
card reader address. If you enter a null line, the IPL device address
is the default of OOC. Part 2. Defining Your VM/370 System 199