Assigning Attributes To A Data Set; Freeing An Allocated Data Set - IBM System 360 User Manual

As3igninq Attributes to a Data Set
TSO data set characteristics are called attributes. Generally, you do
not have to be concerned with attributes because TSO assigns them
automatically. In some instances, however, you may want to allocate a
data set with attributes different from those assigned automatically.
The ATTRIB command provides a way for you to do this.
Basically, you use the ATTRIB command to build a list of the
attributes that you want to assign to a data set. Then you use the
ALLOCATE command, specifying the name of the attribute list as the value
for the USING (attr-list-name) operand. The attributes in the list are
assigned to the data set when it is allocated.
You can refer to the attribute list any number of times during the
remainder of your terminal session. When you finish using the attribute
list, you can use the FREE command to delete it from the system.
The operands of the ATTRIB command correspond to data control block
(DCB) parameters discussed in the following publicati ons:
• IBM ~ystem/360 Operating System: Job Control Language Reference,
GC2S-6704 •
• IBM System/360
O~tinq
System: Data Management Services,
GC26-3746.
You should understand the purpose of DCB parameters as presented in
these publications before using the ATTRIB command.
The example in Figure 7.1 illustrates the use of the ATTRIB command.
In this example, the attributes are the logical record length, the block
size, and the expiration date.
r---------------------------------------------------~-------.
---------,
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attr dchparms Irecl{24) blksize(96) expdt(72111)
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READY
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alIce da('attr.show') using(dcbparms) new bl(SO) sp(l,l) vol(231400)
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READY
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free attrlist(dcbparms)
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L ______________________________________________________________________ J
Figure 7.1 Assigning Attributes to a Data Set
Freeing an Allocated Data Set
Use the FREE command to release any data sets allocated to you. You can
also use this command to change the output class of a SYSOUT data set,
or to release attribute lists created by the ATTRIB command.
To free ~ data set specify its data set name or its file name
(ddname). If your terminal has been allocated as a data set, you must
free it through its file name. You can use the LISTALC command to
obtain the file names and data set names of the data sets allocated to
you. (LISTALC is described in the Section,
II
Listing the Names of Your
Data Sets
n • )
The following examPle frees the data sets allocated in Figure 7 of
the section "Allocating a Data Setn. The output class of the SYSPUNCH
data set is changed to B.
free dataset ( • sys1.maclib' .prog .obj" input.asm) file (sysut1,-
sysut2,sysut3,sysprint,syspunch) sysout(b)
Entering and Manipulating Data 61