DOS 3.3 drive specification

[dalloff@freenet.columbus.oh.us (Dave Althoff)]

Whoever mentioned it before is pretty-much correct.  Almost any DOS
command will accept the slot, drive, and volume attributes.  There are
some restrictions, though.

I believe that all DOS commands assume V0 if a volume number is not
specified, even if the previous  command did specify a volume number.  The
exception is the INIT command, which assigns a volume number to a disk. 
The default value for the INIT command is $FE (254).  Note that the V0
value causes DOS to accept whatever volume value exists for the disk.

As mentioned, once a slot and drive are specified, the selections stick
until a command is issued with a different slot and  drive specification.

The exception to this rule is that when working with TEXT files, the slot,
drive, and volume parameters should not be used with READ or WRITE
commands.  Use the slot and drive parameters with the OPEN command, and
the READ or WRITE commands will automatically select the proper drive and
slot.  This is  particularly useful if you have multiple open files on 
multiple drives.  DOS automatically locates the right one for you (clever,
eh?).

Just getting specific...
--Dave Althoff, Jr.
(written at a mind-blowing 0.8 MHz on an unenhanced Apple ][e running
Kermit at 2400 baud under DOS 3.3.  To the Apple tech guys who said it
couldn't be done: pbbbblblblbbbt!)