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ibm:vm370-lib:cmshelp:access.helpcmd

ACCESS

CMS Commands

access.helpcmd.txt
ACCESS                                                    CMS Transient command

Use the ACCESS command to identify a disk to CMS, establish a filemode letter
for the files on the disk, and set up a file directory in storage.  The
specifications you make with the ACCESS command determine the entries in the
user file directory.  The format of the ACCESS command is:
+----------+------------------------------------------------------------------+
| ACcess   | 191 cuu  A|mode[/ext [*|fn [*|ft [*|fm]]]] [(options...[)]]      |
|          | options:                                                         |
|          | ERASE    MODE0    NODISK   NOPROF                                |
+----------+------------------------------------------------------------------+
where:

cuu      makes available the disk at the specified virtual device address.  The
         default value is 191.  Valid addresses are 001 through 5FF for a
         virtual machine in basic control mode, and 001 through FFF for a
         virtual machine in extended control mode.

mode     assigns a one-character filemode letter to all files on the disk being
         accessed.  This field must be specified if cuu is specified.  The
         default value is A.

ext      indicates the mode of the parent disk.  Files on the disk being
         accessed (cuu) are logically associated with files on the parent disk;
         the disk at cuu is considered a read-only extension.  A parent disk
         must be accessed in the search before the extension. A blank must not
         precede or follow the slash (/).

fn [ft [fm]]
         defines a subset of the files on the specified disk.  Only the
         specified files are included in the user file directory and only
         those files can be read.  An asterisk coded in any of these fields
         indicates all filenames, filetypes, or filemode numbers (except 0) are
         to be included.  (See Usage Notes 3 and 4.)

Options:

ERASE    specifies that you want to erase all of the files on the specified
         disk.  This option is only valid for read/write disks.  (See Usage
         Note 7.)

MODE0    makes mode 0 files visible on a read only disk. Normally they are
         hidden.

NODISK   lets you gain access to the CMS operating system with no disks
         accessed by CMS except the system disk (S-disk) and its extensions.
         This option is only valid if the ACCESS command is the first command
         you enter after you IPL CMS.

NOPROF   suppresses execution of a PROFILE EXEC file.  This option is valid
         only if the ACCESS command is the first command entered after you IPL
         CMS.  On subsequent ACCESS commands, the NOPROF option is ignored.


Usage Notes:

1.  If you have defined disk addresses 190, 191, 192, and 19E in the VM/370
    directory, or if they are defined before you IPL CMS, these disks are
    accessed as the S-, A-, D-, and Y-disks respectively.  Following an IPL of
    CMS, you must issue explicit ACCESS commands to access other disks.
    Ordinarily, you have access only to files with a filemode number of 2 on
    the system disk, or S-disk.  Note that you cannot specify a filemode of S
    with the ACCESS command.

2.  Associated with each CMS disk is a file directory, which contains an entry
    for only those CMS files on the disk to which you have access.  If you use
    the CP LINK command to link to a new minidisk, issue an ACCESS command each
    time.  Do this so that you obtain the appropriate file directory.

3.  The filename, filetype, and filemode fields can only be specified for disks
    that are accessed as read-only extensions.  Also, requesting a subset of
    files creates a file directory in your virtual machine.  For example:
        access 195 b/a * assemble
    gives you read-only access to all the files with a filetype of ASSEMBLE on
    the disk at virtual address 195, and the file directory information is
    stored in your virtual machine.  The command:
        access 190 z/a * * z1
    gives you access to all files on the system disk (190) that have a filemode
    number of 1.  When you access any disk in read-only status, files with a
    filemode number of 0 are not accessed, unless the MODE0 option is
    specified.

4.  You can also identify a set of files on a disk by referring to a filename
    or filetype prefix.  For example:
        access 192 c/a abc*
    accesses only those files in the disk at virtual address 192 whose
    filenames begin with the characters ABC.  The command:
        access 192 c/a * a* c2
    gives you access to all files whose filetypes begin with an A and that have
    a filemode number of 2.

5.  You can force a read/write disk into read-only status by accessing it as an
    extension of another disk or of itself; for example:
        access 191 a/a
    forces your A-disk into read-only status.

6.  When a disk is made a read-only extension of another disk, commands that
    typically require or allow you to specify a filemode may search extensions
    of the specified disk.  The exceptions to this are the LISTFILE and DISK
    DUMP commands.

7.  If you enter the ERASE option by mistake, you can recover from the error as
    long as you have not yet written any new files onto the disk.  (That is,
    you have not yet caused CMS to rewrite the file directory.)  Reissue the
    ACCESS command without the ERASE option.

8.  You should never attempt to access a disk in read/write status if another
    user already has it in read/write status; the results are always bad.

9.  When accessing OS and DOS disks:
    a.  You cannot specify filename, filetype and filemode when you access OS
        or DOS disks, nor can you specify any options.
    b.  In order to see OS and DOS disks, you must have a read/write CMS A-disk
        available if you are going to use the LOAD command with the MAP option.

10. To free an accessed disk, refer to the CMS RELEASE command.

Responses:

DMSACC723I    mode [cuu] <R/O R/W> [-OS -DOS]
    If the specified disk is a CMS disk, this message is displayed if the disk
    is read-only.  If the disk is in OS or DOS format, the message indicates
    the format, as well as whether it is a read/write or read-only disk.

DMSACC724I    cuu1 REPLACES mode (cuu2)
    Before execution of the command, the disk represented by cuu2 was the
    'mode' disk.  The disk cuu1 is now assigned that filemode letter.  This
    message is followed by message DMSACC726I.

DMSACC725I    cuu ALSO = mode [-OS -DOS] DISK
    The disk specified by cuu is the 'mode' disk and an ACCESS command was
    issued to assign it another filemode letter.

DMSACC726I    cuu mode RELEASED
    The disk being accessed at virtual address cuu as a read/write disk is
    already accessed at a different mode.  It is released from that mode.  Or,
    a disk currently accessed at mode is being replaced.
ibm/vm370-lib/cmshelp/access.helpcmd.txt ยท Last modified: 2023/08/06 13:36 by Site Administrator