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set be removed from the catalog.
DSNAME, the second operand,
specifies
the
main
storage
location
of
an area into which you have placed the
fully qualified name of the data set whose references are to be removed.
HOW TO RECATALOG A DATA SET
You recatalog a cataloged data set by using the
CATALOG
and
CAMLST
macro-instructions.
Recataloging
is usually performed when new volume
pointers must be added to the volume list of a data set.
You must build a complete volume list in main storage.
This
volurre
list
consists
of volume pointers for all volumes on which the data set
is stored.
The first two bytes of
the
list
indicate
the
number
of
volume
pointers that follow.
Each 12-byte volume pointer consists of a
4-byte device code, a 6-byte volume serial number, and a 2-byte data set
sequence number.
The sequence number is always zero
for
direct-access
volumes.
(Device codes are contained in Appendix B of this chapter.)
Example:
In
the
following
example,
the
data
recataloged.
A new volume pointer is added to the
previously contained only two volume pointers.
set
named
A.B.C is
volume
list,
which
r---------T----------T-------------------------------------------------,
I
Name
I
Operationl Operand
I
~---------+----------+-------------------------------------------------~
RECATLG
DSNAME
VOLUMES
CATALOG
I
RECATLG
RECATALOG DATA SET A.B.C,
Check Exceptional Returns
ADDING A NEW VOLUME
POINTER TO THE VOLUME
CAMLST
RECAT,DSNAME"VOIUMES LIST.
DC
CL6'A.B.C'
ONE BLANK FOR DELIMITER
DC
H' 3'
THREE VOLUMES
DC
X'30002001'
2311 DISK STORAGE
DC
CL6'000014'
VOLUME SERIAL NUMBER
DC
H' 0'
SEQUENCE NUMBER
DC
X'30002001'
2311 DISK STORAGE
DC
CL6'OOOOlS'
VOLUME SERIAL NUMBER
DC
H'O'
SEQUENCE NUMBER
DC
X'30002001'
2311 DISK STORAGE
DC
CL6'000016'
VOLUME SERIAL NUMBER
DC
H'O'
SEQUENCE NUMBER
---------~----------~-------------------------------------------------
The CATALOG macro-instruction points to the CAMLST macro-instruction.
RECAT,
the
first
operand
of
CAMLST,
specifies
that
a data set be
recataloged.
DSNAME, the second operand,
specifies
the
wain
storage
location
of an area into which you have placed the fully qualified name
of the data
set
to
be
recataloged.
VOLUMES,
the
fourth
operand,
specifies the main storage location of the volume list you have built.
HOW TO READ A DATA SET CONTROL BLOCK FROM THE VOLUME TABLE OF CONTENTS
You
can
read
a
data set control block (DSCB) into main storage by
using the OBTAIN and CAMLST If-acro-instructions.
There are two
waY3
to
specify
the
DSCB that you want read: by using the name of the data set
associated with the DSCB, or by using the atsolute track address of
the
DSCB.
When
you
specify
the name of the data set, a forroat 1 DSCB is read
into main storage.
To read a DSCB other than a format 1 LSCB, you
must
specify an absolute track address.
<DSCB formats and field descriptions
are contained in the System control Block publication).
18
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