re-write is this booting info correct?

Polytropon freebsd at
Wed Dec 30 16:10:03 UTC 2009

On Tue, 29 Dec 2009 16:29:56 +1100 (EST), Ian Smith <smithi at> wrote:
> In freebsd-questions Digest, Vol 291, Issue 3, Message: 1
> On Mon, 28 Dec 2009 21:04:57 +0800 Fbsd1 <fbsd1 at> wrote:
>  > Content-Type: text/plain; charset=windows-1252; format=flowed
> First up, you'd be better off using a non-Windows charset here, as they 
> use weird characters just for ordinary things like quotes, as below.

Good and helpful advice. Even apostrophes get messed up.

> All of these, at least from DOS 3 (c. '86?) use the same MBR setup, a 
> maximum of 4 Primary Partitions, one (and only one) of which may be an 
> Extended DOS Partition, containing as many Logical Drives as you like; 
> they're formed as a linked list, though I never used past Drive J: with 
> OS/2 (HPFS).  (I'm using caps here to refer to the DOS nomenclature)

The number is de-facto limited to 26 maximum for ALL drive
letters - keyword is LETTER: A up to Z. A: and B: are
reserved for floppy disk drives, C: is the booting partition
(usually a primary DOS partition), D: up to Z: can be:
	- other primary partitions
	- optical drives
	- fake drives refering to directories (SUBST command)
	- external drives (INTERLNK / INTERSVR commands)
The order of the drives is somewhat arbitrary, so you
can't always predict drive letter behaviour.

> In all of these, you can't access more than one Primary Partition from 
> any DOS-based OS; if you wish to have drives D:, E:, F: (etc) then these 
> _must_ be in the single Extended Partition - so your statement above is 
> not correct in that respect.

I'm not sure about this. It's long time ago, so my brain isn't
up to date anymore. :-) When I try to remember, I have the
idea in mind that it WAS possible to partition a drive with
primary partitions (max. 4).

I'll check this - and I actually CAN, because I still have
a DOS machine (6.22) running well; it's mostly used for
programming mobile radios and for disk operations in a
museal content (robotron resurrection). :-)

>  > An alternate method is to allocate an “extended dos partition” and then 
>  > sub-divide it into logical dos drives lettered C, D, E, F. One of these 
> Not limited to F: as above (adding the DOS colon as Polytropon suggests)

My suggestion comes from documentation where "C:" is preferred
to "C" (in context of drive letters), like "The C: drive is
the booting drive", or "On floppy A: you'll find no files".

> I'm not sure about NT, but certainly DOS 3 to 7 
> cannot boot from other than drive C: - though DOS Drive C: need not be 
> the first physical disk partition, indeed there can be several, though 
> only the first one marked Active is called C: by DOS on any one boot.

DOS doesn't provide a native means for boot selection, so
this statement appears to be correct in relation to my

>  > Microsoft/Windows partition and the FreeBSD slice is where the operating 
>  > system software is installed. Microsoft/Windows operating system creates 
>  > default folders that share the space in the partition.  The FreeBSD 
> It's not clear what you mean here by 'folders that share the space'?

It seems to refer to the fact that the functional separation
in "Windows" is done through directories ("folders"), instead
of partitions.

Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...

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