Re: How the heck do you format a disk with ProDos?

[shack@deimos.frii.com (Randy Shackelford)]

In article <01bc24c5$156aa880$6c7808ce@vincere1>,
Aaron Pulver <aaronp@paulbunyan.net> wrote:
>
>Tilghman Lesher <lesherjt@vuse.vanderbilt.edu> wrote in article 
>> I think there's a FORMAT command in the P8 code, so adding this
>> command to BASIC.SYSTEM probably would not be that difficult.  I
>> wonder why Apple chose to leave out this command?
>
>There isn't a FORMAT command for the built-in P8 5.25" disk driver, so you
>have to use a program that implements a FORMAT.  I think it was left out
>for space reasons.

The format code for every device ProDOS supports is in its device driver.
This is in the firmware of most devices, like hard disks, 3.5 drives, RAM
disks, etc. With the exception of the disk II, as it basically has no ROM,
and predates ProDOS as well. So any app which wants to format a 5.25 has to
have code to format the disk. Due to space problems, this code was left out
of the disk II device driver.

Device drivers have a call to format the device's media, but it's up to the 
app to build the volume directory, bit map, and boot block. There is an
exception to this though: the 64K RAM disk's driver sets up the directory
and bit map with a format call. No boot block of course, since ya can't
boot from it.

So you can see why this capability was left out of BASIC, and makes it 
necessary to use something like filer to format a disk.
-- 
Randy Shackelford                                 
shack@frii.com