Quoting Ignatios Souvatzis (13-Jun-01 21:48:05):

> On Wed, Jun 13, 2001 at 11:48:23AM +0100, Georges Heinesch wrote:
>> 
>> When I format the drive, should I use ...
>> 
>>     2. newfs /dev/rsd2a
> yes, if you have a.

>>     4. newfs /dev/rsd2c
> almost never - that is the "whole disk" partition.

But what's the difference betweeen c and a in this particular case.

>>     6. newfs /dev/rsd2d
> yes, if you have d.

I did some extensive testing on this now. It came out the that the
following commands are possible / not possible (HDToolBox identifier
0x4e425207 [root]):

    # newfs /dev/rsd2a (possible)
    # newfs /dev/rsd2c (possible)
    # newfs /dev/rsd2d (not possible!)

The difference of a and c is nil, except that c takes a little bit
longer for newfs (no idea why). The reported disk capacity after newfs
is however different. After newfs a shows 610.304 Bytes less than
after newfs c (also no idea why).

The difference lies however in what is mounted, it doesn't matter
(capacity wise) if the disk is formatted as a or c, but the mounting
makes the difference. If a is mounted, the disk has those 610.304
Bytes (596K - 2 tracks since 596 blocks per track and a block has 512
Bytes) less as if it is mounted as c.

This means that even if newfs a is done, c can be mounted and vice
versa.

Using HDToolBox identifier 0x4e425507 [other partitions]):

    # newfs /dev/rsd2a (not possible!)
    # newfs /dev/rsd2c (possible)
    # newfs /dev/rsd2d (possible)

Analog results as above.

-- 
Cu  Georges Heinesch, Luxembourg
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