DLBL catdd identifies the VSAM catalog (defined by a previous DLBL
definition) which contains the entry for this data set. You must use the CAT option when the data set you are
creating or identifying is not cataloged in the current job
catalog. catdd is the ddname in the DLBL definition for
the catalog. BUFSP nnnnnn
specifies the number of bytes (in decimal) to be I/O buffers by VSAM data management during
execution, overriding the BUFSP value in the ACB file. The maximum value for nnnnnn is 999999;
commas are not permitted.
used for
program
for the
embedded
1. To display all of the disk file definitions in effect, enter:
dlbl
The response will be:
ddname DISK fn ft
If no DLBL definitions are in effect, the following message is
displayed: DMSDLB3241 NO USER DEFINED DLBL'S IN EFFECT
2. To enter an OS or DOS file identification on the DLBL command line,
it must consist of 1-to 8-character qualifiers separated by
periods, with a maximum length of 44 characters, including periods. For example, the file TEST.INPUT.SOURCE.D could be identified as
follows:
dlbl ddl c dsn test input source d (options ••• Or, it may be entered interactively, as follows:
dlbl ddl c dsn ? (options DMSDLB220R ENTER DATA SET NAME:
test.input.source.d
Note that when the data set name is entered interactively, the data
set name must be entered in its exact form; when entered on the
DLBL command line, the periods must be omitted. You must use the interactive form to enter a DOS file-id that
contains embedded blanks or hyphens.
3. In DJS/VS, a data set that has been defined as is opened
with an error code of X· 11'. CMS supports the DUMMY operand of the
DLBL command in the same manner. OS users should not use the DUMMY operand in CMS, since a dummy data set does not return, on open, an
end-of-file indication.
62 IBM VM/370 CMS Command and Macro Reference

DLBL
1. DLBL definition must be associated with a system or programmer
logical unit assignmentr previously made with an ASSGN command.
Specify the SYSxxx option on the first, or only, DLBL definition for a particular ddname. Many DLBL definitions may be associated
with the same logical unit. For example:
assgn sys100 b
dlbl ddl b cms test filel (sysl00 dlbl dd2 b cms test file2 (sys100 dlbl ddl cms test file3
is a valid command sequence.
2. The following special ddnames must be used to define DOS private
libraries, and must be associated with the indicated logical units: IJSYSSL IJSYSRL IJSYSCL Logical !Inii __ _ SYSSLB SYSRLB SYSCLB 1ibra£y Source statement
Relocatable
Core image
These libraries must be identified in order to perform librarian
functions (with the SSEBV, ESERV, DSERV r or RSERV commands) for
private libraries; or to link-edit or fetch modules or phases from
private relocatable or core image libraries (with the DOSLKED and
FETCH commands).
3. Each DOS file has a CMS file identifier associated with it by
default; the filename is always FILE and the filetype is always the
same as the ddname. For example, if you enter a DLBL command for a DOS file MOD.TEST.STREAM as follows:
dlbl test c dsn mod test stream
then you can refer to this OS data set as FILE TEST when you use
the STATE command: state file test When you enter a DLBL command specifying only a ddname and mode r as
follows:
dlbl junk a CMS assigns a file identifier of FILE JUNK Al to the ddname JUNK. 4. The FILEDEF command performs a function similar to that of the DLBL
command; you need to use the FILEDEF command in CMS/DOS only: • When you want to override a default ddname for an assembler
input or output file. • When you want to use the MOVEFILE command to process a file.
5. If you use the DUMMY operand, you must have issued an ASSGN command
specifying a device type of IGN
r or ignore, for the SYSxxx unit
specified in the DLBL command, for example, Section 2. CMS Commands 63