| Title: | DECmcc user notes file. Does not replace IPMT. |
| Notice: | Use IPMT for problems. Newsletter location in note 6187 |
| Moderator: | TAEC::BEROUD |
| Created: | Mon Aug 21 1989 |
| Last Modified: | Wed Jun 04 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 6497 |
| Total number of notes: | 27359 |
I am using MCC MIR routines to manipulate our system management
entities. I have a question about MCC_MIR_WRITE_ATTR_DATA routine.
If I have an entity class "SERVER" and instance "X" created, and two
attributes A1 and A2 associated with "SERVER X", so I create an instance
repository to store instance X and an attribute repository to store A1
and A2.
Now, I want to set the attribute A1 to a different value, the question
is, in my API, 1) Do I just simply pass the new value (using
ILV-encoded format) of A1 to MCC by issuing the MCC_MIR_WRITE_ATTR_DATA
call so that MCC is intelligent to know which attribute I am dealing with
(by decoding the ILV list) and updates that attribute? or
2) Do I need to issue MCC_MIR_READ_ATTR_DATA call first to read the entire
attribute list and update A1 with new value and then call
MCC_MIR_WRITE_ATTR_DATA?
The MCC MIR document talks about something related to this question but
not so clearly. I guess 2) is the answer, but I am not sure.
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 223.1 | bag 'o bits | COOKIE::KITTELL | Richard - Architected Info Mgmt | Wed Aug 01 1990 16:14 | 8 |
I'm as new to this as you are, but my experience says what is in the attr buffer when you write is what you get back when you read it. The mir sees your data as a stream of bytes with a specified length, and makes no attempt to insert one ILV-encoded attr value into an existing stream, and any other operation that would assume knowing the structure of your data. | |||||
| 223.2 | MIR routines don't look inside the buffer | TOOK::GUERTIN | Wherever you go, there you are. | Wed Aug 01 1990 22:00 | 25 |
RE:.1 Yes, the MIR routines really only looks at the length and
starting address of the buffer (i.e., it's just a stream of bytes).
RE:.0 If you have two attributes in the your private attribute
repository, and you wish to modify one, without changing the other,
you must 1) read the record, 2) modify the record (using ILV gets and
puts, in your case) 3) write it back out. If you need transaction
processing, then that would involve more work.
I had a routine which would search through an ILV encoding and just
modify the value for a given ID code (by copying it to another ILV
buffer). I should try and find it, someone may find it useful.
BTW, The SRM (Section 10.12.3) states:
"... If the attribute partition is used often for passing through the call
interface, then it may be useful to ILV-encode the data. However, the
MIR routines do not make any assumptions about the storage of the
attributes. If the data is not ILV-encoded, the owner of the data must
know the record layout. If it is ILV-encoded, the owner of the data
should call the ILV routines to build and parse the attribute partition
record."
Hope this clarifies things a little.
-Matt.
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