[Coco] Curious DECB File o bytes

Luis Fernández luis46coco at hotmail.com
Sat Sep 8 23:42:32 EDT 2012


I think the engineers were wrong at all
can not book granules


There are 68 granules ok
but the track 17, 18 sectore, 1 vacuum could have been used backup fat but not (did not occur)


Then the fat sector 2


then 16 sectors = 4096 Bytes serves dir for 128 entries of 32 bytes each


but no, only use one per granule 68, and 0 byte files, no?, and also deleted files?.


If not deleted files on write, could undelete, but no, reused in the next file.


Why not reuse when there are no more free entries (128), could have been UN-deleted many files, 
if they had used only new granules and reuse only when there were no more new, 
used granules would be kept but users would free. Perfect


Also 32 bytes for directory entry? 16 bytes are used, and 16 reserved for that?


256 entries fit
We could have at least copy of dir


Name disks
dates for file
Disc dates

copy of fat
dir copy of
undelete or unerase


how to record on the dragon is much better
160 entries by sector without waste, copy of all dir


Track 20 is the same in 16


DECB a disaster


--------------------------------------------------------------------------------- 
Making 
CoCoDskUtilPack V 1.1.3A.zip, Scan magazines and organize maltedmedia
http://cococoding.com/cocodskutil/ Thank Aaron Wolfe
http://www.tandycoco.com Thank Brian Blake and Stephen Fischer
My personal blog: http://www.luis45ccs.blogspot.com, 
Excuse my English, I use google translator, my language is Spanish, I'm Spanish but I live in Venezuela
---------------------------------------------------------------------------------

> Date: Sat, 8 Sep 2012 21:23:56 -0600
> From: lost at l-w.ca
> To: coco at maltedmedia.com
> Subject: Re: [Coco] Curious DECB File o bytes
> 
> I don't believe the granule size is Luis's confusion. Instead, his 
> confusion is that a file with no data in it still uses a granule. This 
> is, in fact, correct behaviour. The reason is as follows:
> 
> In each directory entry, one of the bits of data is the first granule 
> number. This is not an ordinary number in the granule chain. It must 
> always point to a granule.
> 
> Thus, there is always at least one granule allocated. Now, this is 
> actually quite logical because normally one creates files to actually 
> hold data. Thus, it is logical to allocate at least some space for the 
> file when it is created. Doing so also makes the code for handling the 
> disk files simpler too.
> 
> It does seem logical that an empty file would use no space other than a 
> directory entry, and that is the case with many file system. However, 
> the DECB file system is not one that works that way.
> 
> On 12-09-08 07:08 PM, Bill Pierce wrote:
> >
> > I think I'm right in saying, when you create a new file in Disk Basic, HDBDOS, or RGBDOS, 1 granule is allocated to the file. So your test on an empty disk would allocate 1 gran but no bytes written yet.
> >
> > OPEN "O", # 1, "TEST"
> > CLOSE
> > TEST uses 1 granule zero bytes
> >
> >   Disk Basic writes to disk in 1 granule segments (9x 256 byte sectors). A waste of disk space but, it was what we had at the time. OS-9 gave us some relief with 1 sector writes. It gave us more file space.
> >
> > Music from the Tandy/Radio Shack Color Computer 2 & 3
> > https://sites.google.com/site/dabarnstudio/
> > Bill Pierce
> > ooogalapasooo at aol.com
> >
> >
> >
> >
> > -----Original Message-----
> > From: Luis Fernández <luis46coco at hotmail.com>
> > To: COCO <coco at maltedmedia.com>
> > Sent: Sat, Sep 8, 2012 7:57 pm
> > Subject: [Coco] Curious DECB File o bytes
> >
> >
> >
> >   "O", # 1, "TEST"
> > CLOSE
> > TEST uses 1 granule zero bytes
> >
> >
> > You should not use granules
> >
> > ---------------------------------------------------------------------------------
> >
> > Making
> > CoCoDskUtilPack V 1.1.3A.zip, Scan magazines and organize maltedmedia
> > http://cococoding.com/cocodskutil/ Thank Aaron Wolfe
> > http://www.tandycoco.com Thank Brian Blake and Stephen Fischer
> > My personal blog: http://www.luis45ccs.blogspot.com,
> > Excuse my English, I use google translator, my language is Spanish, I'm Spanish
> > but I live in Venezuela
> > --------------------------------------------------------------------------------- 		 	   		
> >
> >
> > --
> > Coco mailing list
> > Coco at maltedmedia.com
> > http://five.pairlist.net/mailman/listinfo/coco
> >
> >
> >
> > --
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> > Coco at maltedmedia.com
> > http://five.pairlist.net/mailman/listinfo/coco
> >
> 
> 
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