[Tfug] windows to Linux

[Bexley Hall]

Hi Liz,

> I'm probably confused with partitions vs. actual disks.

Argh!  There is no easy way to express this pedantically.
*One* usage of the term (old) has physical disks cut up
into pieces called "partitions".  Originally, partitions were
"full cylinders" (think of the disk as having concentric "tracks"
onto which information is recorded -- sort of like the groove in
an old vinyl "LP" -- except there was only *one* groove on an LP
that *spiralled* inward).

So, if your physical disk had 100 cylinders, you might cut it
up into 1-20, 21-65, 66-80 and 81-100.  Or, any other combination
that yields no more than four "groups" of cylinders (the cylinders
in each partition had to be contiguous.  but, partition #1 could
be located physically *after* partition number 2 on the disk,
if you wanted it to be so).

This allows you to treat each "partition" as a seperate entity.
Some OS's would call each of them a different LOGICAL disk
(so, one partition might be C:, the next D:, etc.).

Each partition has a "type" flag.  These numbers are assigned
by *convention*.  So, you could say partition 1 is a DOS partition
and partition 2 is a NetBSD partition, etc.  In theory, nobody
stomps on anybody else's partition (unless you are MS and freely
stomp wherever you want!  :< )

The "partition table" is stored in the MBR (Master Boot Record)
on i386 machines (other architectures have other ways of doing
things).  Since the MBR is very small (hundreds of bytes),
and *also* has to include the code that actually starts up
the operating system loader, the partition table is small;
a maximum of four entries.

Some boot loaders (the code that resides in the MBR) present
a menu that allows you to pick which of these partitions to
"mark as ACTIVE" and boot off of.  Other boot loaders just
boot off of whichever partition *is* marked as active.  Still
other boot loaders may just always boot off of "partition X".

Since the code to mark a partition as active, etc. is bigger than
the space available in the MBR, there is often another utility
that modifies the MBR at your request -- and the partition table
within it.  In DOS, this is FDISK and its various options.
(In NetBSD it is a different form of fdisk).  E.g., FDISK /MBR will
replace the boot code in the MBR with the (ahem) "correct" (as
far as MS is concerned) boot loader code (I can't recall if it also
wipes out the partition table or, probably, carefully preserves it)

> I figured since the bios showed me D: that it was
> a partition.  Maybe I actually had a physical D: drive
> in there?

Doubtful; in most laptops one physical disk possibly *partitioned*
to look like more than one (there are good reasons for doing this but
beyond the scope of this explanation).  Again, I don't know what your
BIOS looks like so I can't comment on what it is telling you.

> It's an HP Compaq and my housemate said
> that it's not running wih the fastest chip on the block.

Probably an older model, then.  <shrug>  I am usually more
wary of *new* models being too far ahead of the software
so yours is probably OK.

> It's never been the same since my cat
> fell in the swimming pool and tried to climb on top of it
> while she was still wet and I was working with it on my lap.

Ah.  At least you didn't spill *soda* in it!  :-/
 
> Modem went out, and I've been using
> a silly ass usb wireless deal since.

Modem could just be a high impedance "short".  But, disassembling
the laptop just to fix that is often not worth the effort.
(BTW, if you have a PCMCIA clot to spare and cherish using
modems, I can send you one)

> serving tray might just be the best use if not a cat warmer.

Naw, you can always find *some* use for them!  I used to have a
laptop with *built in* power supply (!) that I used as a
small DNS/TFTP/font/etc. server for a while.  Quite low power,
took up very little space *and* I didn't have to run it
headless as it came with a keyboard and display!  :>

--don