[net.micro.apple] uncatalogable files

ST802414@BROWNVM.BITNET (CHRISTOPHER CHUNG) (10/09/86)

Does anyone know how to find out the names of files that do not
show up when you type in CATALOG.  I know they are on the disk.
How do you go about accessing them?

Thanks,
Chris

wtm@neoucom.UUCP (Bill Mayhew) (10/10/86)

Hi,

	Most of the time the file name is a control or some other
unprintable / untypable character, presuming that the file is
allocated through the normal file system.

	The best way to get at them is to use a sector editor.
There are a number of P/D disk editors.  I think that you can also
get such things from companies like Beagle Brothers.  Before you go
to work on your disk, it would be a good idea to get the (Pro) DOS
technical referece manual from Apple/Addison-Wesley and/or the
Beneath the Apple DOS and/or Beneath Apple ProDOS.

	With a sector editor, you can read the sector(s) that
contain the catalog entries into memory and change the filename
fields to contain recognizable characters, and then rewrite to the
disk.  Hopefully the disk you're sector zapping is a back-up of the
original!!

	Sometimes, you can use DOS 3.3 "FID" or else the ProDOS
"FILER" to help you rename a file that you accidentally typed a
control character into the filename.  Just specify the rename
option, and use the "=" wildcard.  When the offensive file is
displayed as a blank line, or whatever, simply rename it; this
often works.

	Some protected software uses blank filenames as a cover
for sectors that they read and write directly.  If you move the
blank file, the original allocated sectors will be released in the
sector bit map and possibly allocated to other files, thus cuasing
corruption of the disk.

Hope this gives you a couple of ideas,
Bill

Bill Mayhew
Division of Basic Medical Sciences
Northeastern Ohio Universities' College of Medicine
Rootstown, OH  44272    USA    phone:  216-325-2511
(wtm@neoucom.UUCP  or  ...!cbosgd!neoucom!wtm)

hlb@crash.UUCP (Howard L. Brandell) (10/10/86)

You can try using COPY II+ of course and another method is to boot DOS 3.3
and enter CALL 42350.  I don't know the call for ProDOS.

sdh@joevax.UUCP (The Doctor) (10/10/86)

> Does anyone know how to find out the names of files that do not
> show up when you type in CATALOG.  I know they are on the disk.
> How do you go about accessing them?
>

There are two types of files:
1) files that are part of the normal catalog, but have control characters
embedded in them to prevent you from seeing them, for example,
*B 005 FILEhhhhhhhhhhh
where h stands for backspace will show thw filename as a blank.
To see the file, just type
SPEED = 0
at the applesoft prompt, and it will slow the output down so you can see
the file name and then see it erased.  You will not be able to see other
control characters, though.
Solution 2:
There is a program in the original DOS 3.2 manual (it may be in the
3.3 manual too) that is an assembly language subroutine that intercepts
the output and changes control characters to inverse.  This works like
a dream.
Solution 3:  Use a disk scanning program to view the catalog (traditionally
on track $11) and it should be able to show you all the control characters.
You should then be able to change them to printing characters.
NOTE: if you change the finle name, you may have to change it back or
things might not work at all.

2) the second kind of invisible file has no entry in the catalog.  It
exists on the disk as a normal file, and has the sectors allocated for it
removed from the Volume Table of Contents (VTOC).  Whenever you delete a file,
it removes it from the directory, and frees up the sectors it used in the
VTOC. When these files are created, they usually create the file normally,
the delete it, and put back its entry in the VTOC.  These are harder to find
since you must know where to look first.  You will need a disk scanning
program to do this.  If you do not understand how DOS 3.3 disk are formatted
and how files are stored DO NOT attempt to poke around things this way,
unless you make copies of what you're looking at.  It is VERY easy to kill
disks doing this. Read the DOS 3.3 manual first, or Beneath Apple DOS.

Steve Hawley
joevax!sdh