[Info-vax] Re; Spiralog, RMS Journaling (was Re: FREESPADRIFT)

[Johnny Billquist]

On 2016-06-30 14:48, VAXman- at SendSpamHere.ORG wrote:
> In article <nl0k69$nov$1 at Iltempo.Update.UU.SE>, Johnny Billquist <bqt at softjar.se> writes:
>> On 2016-06-29 15:45, VAXman- at SendSpamHere.ORG wrote:
>>> In article <nl0gec$fke$1 at Iltempo.Update.UU.SE>, Johnny Billquist <bqt at softjar.se> writes:
>>>> It is not the size of the file on the disk. Simple as that.
>>>
>>> You're too thick.
>>
>> Calling an apple a pear won't make it so.
>>
>> What you try to talk about is the size of your data on the disk, which
>> is not the same as the size of the file on the disk.
>> And we have already established that figuring out the size of your data
>> on the disk is also not doable in VMS.
>>
>> You can call ma any number of names, if that makes you happier. But at
>> the end of the day, nothing have changed. And starting to call names is
>> really not much of a technical argument.
>
> Well, I know you don't want to go beyond your precious "C" but, since you do
> seem to be implying sequential files, you might find some solace in the RMS
> XABITM XAB$_FILE_LENGTH_HINT.  I can show you how to invoke the RMS from "C"
> if you request.

Your assumption on my C preference is incorrect. I know C. Don't mean I 
don't know other languages, or that C is my preferred language. It's a 
language that sometimes is useful, but if I can choose, I'll take 
MACRO-11 thank you very much.

And at the end of the day, your file have still taken the same amount of 
space on the disk, no matter where your EOF pointers point to. And 
unless VMS works differently than RSX (which I seriously doubt), the 
file size, as used on the disk, is something kept track of by the ACP, 
which is what deals with the actual file.
RMS is the layer that cares about the EOF pointer. But RMS do not deal 
directly with the disk, but is actually just dealing with the file, as 
given by the ACP. So your EOF pointer is not even something the actual 
file level layer is even aware of. Now, I know that the water is much 
more muddled on the VMS side. In RSX the separation between these layers 
are very simple and clear, and you don't even have to use RMS when you 
access your file. You can do your IO requests directly to the ACP, if 
you want to.

	Johnny