DLBL
DLBL Use the DLBL command: • In CMS/DOS, to define DOS and CMS sequential disk files for program
input/output; to identify DOS files and libraries; to define and
identify VSAM catalogs, clusters, and data spaces; and to identify VSAM, DOS, or CMS files used for VSAM program input/output and access
method services functions. • In eMS, to define and identify VSAM catalogs, clusters, and data
spaces; to identify VSAM files used for program input/output; and to
identify input/output files for AMSERV. The format of the DLBL command is:
r -, I I r r 1 1 I DLBL Iddname {mode} ICMS fn ft 1 [ (optionA optionB [) ]] 1 , , DUt1t1Y 1£t1S I I I , L J
1 I I I , I r ,
1 I , ddna me
{moae }'DSN quaIl [ qua12 ••• qualn ] I I I I DUMMY IDSN ? , 1 I I L .J , , I [ (option A optionB optionC [) ]] I I I " I Iddname CLEAR " I I * " I L J , I QEiiQn!: QEtiQnB: , 1 [ SYSxxx] [ PERM] [ VSAM ] , I r ,
r 1 , I I£HANGE I IEXTENTI , 1 INOCHANGEI ,MULT I I I L .J L .J , I [CAT catdd] , , [BUFSP nnnnnn] , L --' NQi§: The operands and options of the DLBL command are described below. Usage notes are provided for general usage, followed by additional notes
for CMS/DOS users, and then additional notes for as VSAt1 users.
ddname
mode DUMMY specifies a one-to seven-character program ddname (OS) or
filename (DOS), or dname (as specified in the FILE parameter
of an access method services control statement). An asterisk
(*) entered with the CLEAR operand indicates that all DLBL
definitions, except those that are entered with the PERM
option, are to be cleared.
specifies a valid CMS disk mode letter and
filemode number. A letter must be specified; if
not specified, it defaults to 1. The disk must
when the DLBL command is issued.
optionally,
a number is
be accessed
specifies that no real I/O is to be performed. A read
operation results in an end-of-file condition and a write
operation results in a successful return code. DUMMY should
not be used for OS VSAM data sets (see Usage Note 3). 60 IE! eMS Command and Macro Reference

CLEAR
DLBL
removes any existing definitions for the specified ddname.
Clearing a ddname before defining it ensures that a file
definition does not exist and that any options previously
defined with that ddname no longer have any effect. fn ft indicates that this is a and the file identifier (fn
ft) that follows is a CMS filename and filetype.
FILE ddname is the default CMS file identifier associated with
all non-CMS data sets. (See Usage Note 3 for CMS/DOS users.) DSN indicates that this is a non-CMS file.
? indicates that you are going to enter the data set name
interactively. When prompted, you enter the data set name or
fileid in its exact form, including embedjed blanks, hyphens,
or periods. quaIl [quaI2 •.• qualn] Sy Sxx: x
PERM
is an as data set name or DOS file-ide Only data sets named
according to standard as conventions may be entered this way; you must omit the periods between qualifiers. (See Usa.ge Note
2. ) (CMS/DOS only.) indicates the system or programmer logical
unit that is associated with the disk on which the disk
file resides. The logical unit must have been previously
assigned with the ASSGN command. If a DLBL definition is
already in effect for the specified ddname, SYSxxx may be
omitted; otherwise, it is required.
indicates that this DLBL definition can be cleared only
with an explicit CLEAR request. It will not be cleared
when the DLBL * CLEAR command line is entered.
All DLBL definitions, including those entered with the PERM option, are cleared as a result of a program abend or HI
(halt execution) Immediate command. indicates that any existing DLBL for this ddname is not to
be but that conflicting options are to be
overridden and new options merged into the old definition.
Both the ddname and the file identifier must be the same in
order for the definitions to be merged. NOCHANGE does not alter any existing DLBL definition for the
specified ddname, but creates a definition if none existed. VSAM indicates that the file is a VSAM data set. This option
must be specified for VSAM functions unless the EXTENT, MULT, CAT, or BUFSP options are entered or the ddnames IJSYSCT or IJSYSUC are used. EXTENT indicates that you are going to use access method services
to define a VSAM catalog, data space, or unique cluster and
you want to enter extent information. MULT indicates that you are going to reference an existing
multivolume data set and you want to enter the volume
specifica tions. Section 2. CMS Commands 61