binary format list log parameters and ascii list log parameters

Gerry Houlder gerry.houlder at seagate.com
Thu Aug 18 06:44:25 PDT 2011


Formatted message: <a href="http://www.t10.org/cgi-bin/ac.pl?t=r&f=r1108181_f.htm">HTML-formatted message</a>

Let's not forget that the page header and parameter header bytes have the
same definition for both "ASCII data parameters" and "binary data
parameters". The FORMAT & LINKING field only describes the data within its
associated parameter and has no bearing on the parameter header.
On Thu, Aug 18, 2011 at 7:12 AM, Ralph Weber <roweber at ieee.org> wrote:
> * From the T10 Reflector (t10 at t10.org), posted by:
> * Ralph Weber <roweber at ieee.org>
> *
> Fred,
>
> Does not your conclusion mean that ASCII format list parameters
> must be at least 32 bytes (20h) in length?
>
> All the best,
>
> .Ralph
>
>
> On 8/17/2011 5:25 PM, Knight, Frederick wrote:
>
>> "3.1.11 ASCII format list log parameter: a log parameter that contains
>> ASCII data in a list format. See 7.3.2.2.2.4"
>>
>> So, now I need to understand what ASCII data is, so I look at 4.4.1:
>>
>> "4.4.1 ASCII data field requirements
>> ASCII data fields shall contain only ASCII printable characters (i.e.,
>> code values 20h to 7Eh) and may be terminated with one or more ASCII
>> null (00h) characters."
>>
>> Therefore, anything not in the range 20h to 7Eh makes it NOT ASCII.
>>
>> Yes, I think a reference to 4.4.1 would be helpful.
>>
>> I can't find any definition for what binary data is, so that means to
>> me, that it can be anything (byte values in the range 00h to FFh).
>>
>> One key difference is the meaning of 00h.  If you report the data as
>> ASCII, then an application must stop parsing the data when it hits the
>> 00h, but if it is BINARY data, then the application keeps parsing
>> (because 00h is part of the data).
>>
>> So if I understood what Ralph said, I think that means I come the
>> opposite conclusion:
>> If the data is all in the range 20h to 7Eh, then it is ASCII, if ANY
>> byte contains a value not in that range, then it is BINARY.
>>
>>   -	OR put another way  -
>>
>> The presence of one BINARY field in a log parameter pushes it out of the
>> ASCII format list camp and into the BINARY format list modus operandi.
>>
>>	  Fred
>>
>> -----Original Message-----
>> From: Ralph Weber [mailto:roweber at IEEE.org]
>> Sent: Wednesday, August 17, 2011 3:31 PM
>> To: T10 Reflector
>> Subject: Re: binary format list log parameters and ascii list log
>> parameters
>>
>> * From the T10 Reflector (t10 at t10.org), posted by:
>> * Ralph Weber<roweber at ieee.org>
>> *
>> Okay! So, the question is which, if any, of the following
>> statements are true.
>>
>> 1) ASCII format list parameters contain *all* ASCII fields.
>> 2) Binary format list parameters contain *all* binary fields.
>>
>> To belabor the obvious, both statements cannot be true unless
>> people are *very* careful about how the construct log parameters.
>>
>> IMHO The presence of the control byte and parameter length fields
>> in an ASCII format list parameter negates any possibility that
>> statement 1) can be true. The only statement in the pair which
>> can ever be 100% true is 2).
>>
>> Based on this and a little leap of faith, I would like to claim
>> that the presence of one ASCII field in a log parameter pushes
>> it out of the Binary format list camp and into the ASCII format
>> list modus operandi.
>>
>> Let's see if this sets the T10 Reflector on fire for a day
>> or two.
>>
>> All the best,
>>
>> .Ralph
>>
>> P.S. If I have parsed Curtis' description correctly, the current
>> specification is correct ... a lucky break eh!
>>
>> On 8/17/2011 1:17 PM, Ballard, Curtis C (StorageWorks) wrote:
>>
>>> * From the T10 Reflector (t10 at t10.org), posted by:
>>> * "Ballard, Curtis C
(StorageWorks)"<curtis.**ballard at hp.com<curtis.ballard at hp.com>
>>> >
>>> *
>>> This question came up because SMC-3 leveraged a log page which has
>>>
>> parameters that are not entirely ASCII but sets the FORMAT AND LINKING
>> field to 01b, ASCII format list.  We're trying to figure out whether to
>> change to match what we think the FORMAT AND LINKING should be and be
>> inconsistent with existing implementations that may be able to be
>> leveraged but set the field differently or leave the field as is.
>>
>>> The implication is that the ASCII format list log parameter value is
>>>
>> all ASCII but I can't find anything in SPC-4 (r31) that says what the
>> PARAMETER VALUE field of an ASCII format list log parameter contains.
>> The closest statement I found is the definition but that is never
>> referenced from any of the text describing the log parameter so it is a
>> bit tricky to find and even that doesn't really say the PARAMETER VALUE
>> is ASCII data, it just says the parameter 'contains' ASCII data.
>>
>>> "3.1.11 ASCII format list log parameter: a log parameter that contains
>>>
>> ASCII data in a list format. See 7.3.2.2.2.4"
>>
>>> Table 301 specifies the log parameter type as indicated by the FORMAT
>>>
>> AND LINKING field.
>>
>>> "01b --- ASCII format list --- 7.3.2.2.2.4"
>>>
>>> Section 7.3.2.2.2.4 is only defining the parameter control byte and
>>>
>> doesn't define what is allowed to be in the PARAMETER VALUE field of an
>> ASCII format log parameter.
>>
>>> The best reference I can find in that section is:
>>>
>>> "any log parameter that is defined to be an ASCII format (see 4.4.1)
>>>
>> list log parameter"
>>
>>> But section 4.4.1 never defines what it means to be an "ASCII format".
>>>
>> That section is all about ASCII data fields and the sentence with that
>> reference is about a log parameter, not a data field.  Table 299 defines
>> the log parameter as containing fields and bits that aren't ASCII so it
>> isn't clear what the reference is intending to clarify.
>>
>>> I think this paragraph should reference back to 3.1.11 after
>>>
>> 'parameter' and probably not reference 4.4.1.
>>
>>> The table that says how to fill in the FORMAT AND LINKING field sends
>>>
>> you back to table 301 and we start all over again.
>>
>>> I believe that the intent was probably something like "the PARAMETER
>>>
>> VALUE field of a ASCII format list log parameter is an ASCII data field
>> (see 4.4.1)" but I can't prove that from the text I have.
>>
>>> Curtis Ballard
>>> Hewlett Packard
>>>
>>> -----Original Message-----
>>> From: owner-t10 at t10.org [mailto:owner-t10 at t10.org] On Behalf Of Ralph
>>>
>> Weber
>>
>>> Sent: Wednesday, August 17, 2011 10:46 AM
>>> To: T10 Reflector
>>> Subject: Re: binary format list log parameters and ascii list log
>>>
>> parameters
>>
>>> * From the T10 Reflector (t10 at t10.org), posted by:
>>> * Ralph Weber<roweber at ieee.org>
>>> *
>>> Is it fair to assume that the difference between ASCII data
>>> and binary data is not of interest to the SMC working group?
>>>
>>> All the best,
>>>
>>> .Ralph
>>>
>>> On 8/17/2011 11:20 AM, Kevin D Butt wrote:
>>>
>>>> The SMC working group has a question.  SPC-4 describes binary format
>>>> list log parameters and ascii list log parameters.  The only
>>>> difference we can find is in the value in the FORMAT AND LINKING
>>>> field.  We can find no specified behavior differences.  What are the
>>>> functional differences besides the parameter control byte?
>>>>
>>>> Thanks,
>>>>
>>>> Kevin D. Butt
>>>> SCSI&   Fibre Channel Architect, Tape Firmware
>>>> Data Protection&	Retention
>>>> MS 6TYA, 9000 S. Rita Rd., Tucson, AZ 85744
>>>> Tel: 520-799-5280
>>>> Fax: 520-799-2723 (T/L:321)
>>>> Email address: kdbutt at us.ibm.com
>>>>
http://www-03.ibm.com/servers/**storage/<http://www-03.ibm.com/servers/storag
e/>
>>>>
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