This subcommand is valid only with the READ UPDATE
function.
The CHANGE subcommand allows you to change the following:
- The name
- The RBA (relative byte address) of the index entry displayed
- The RBA of the segment specified
- The compression count (or the entry identifier byte or both)
The changed entry is displayed. Enter the NEXT subcommand or a
null line to display the next entry.
Syntax of the CHANGE subcommand of DISPLAY
CHANGE [ENTRY(entryname) CLASS(classname)]|[SEGMENT(segment-name)]
[GENERIC]
[RBA(rba)]
[COMP(xx)]
DUPLICATE|NODUPLICATE
where:
- ENTRY(entryname)
- Specifies the index entry where the display begins. If you do
not specify an entry name, the display begins at the first entry in
the index block; the entry name can be from 1 to 255 alphanumeric
characters, which can be enclosed in quotation marks or not, and can
contain hexadecimal data.
To specify a mixed-case entry name, you
must enclose entryname in quotations. If you do
not enclose entryname in quotations, alphabetic
characters in entryname are treated as uppercase
characters, regardless of the case in which you enter them.
If
you specify an entry name, you must specify a class name.
- CLASS(classname)
- Must be one of the following:
- GROUP
- USER
- DATASET
- The class name of the general resource
The length of name plus the compression count cannot exceed
255. To create a fully compressed name, specify ENTRY (‘ ’), where
the entry name is a null string, with a nonzero compression count.
For a discussion of compression and an explanation of index blocks
and encoding, see Index entries.
- SEGMENT(segment-name)
- Specifies the segment RBA to be changed.
The BASE segment cannot
be specified as the segment name.
The ENTRY and CLASS keywords
and the SEGMENT keyword are mutually exclusive. If both are specified,
SEGMENT is ignored.
If you specify SEGMENT, only the RBA (relative
byte address) of the SEGMENT is changed.
- GENERIC
- Indicates that the index entry name specified in ENTRY(entryname)
is a generic name.
- RBA(rba)
- The value of rba can be from 1 to 8 hexadecimal
characters or from 1 to 10 decimal characters.
- COMP(xx)
- The front-end compression count. xx is limited
to one less than the length of the entry, and never exceeds 254. xx can
be specified as decimal or hexadecimal characters.
- DUPLICATE
- Means that you want to make the entry a duplicate of the entry
immediately following. This entry that immediately follows might be
on the same block or appear at the beginning of the next block.
- NODUPLICATE
- Means that you do not want the current entry to be a duplicate
of the entry immediately following.
There is no default on this
keyword; if you do not specify DUPLICATE or NODUPLICATE, the entry
identifier byte is not changed. It remains at its previous setting.
Specify only those keywords that you want to change. The others
remain at their previous settings.
The BLKUPD command does not perform any checking to see if you
have specified the appropriate keyword values to be changed. You must
be very careful because specifying an incorrect keyword value or omitting
a keyword and its value can produce unpredictable results.