D7314@UWAVM.BITNET (10/10/86)
Date: Thu, 9 Oct 86 16:11 PDT From: Patrick Ryan <D7314@UWAVM> Subject: Re: Files not on Catalog To: Apple Mailing list <INFO-APPLE@BRL.ARPA> ================================================================================ > 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 2 ways to do this, one of which is quite fallable but easy, one of which is surefire but difficult (both assume that the disk isn't copy-protected ). One way is to use Copy ][+ or some such utility and use the 'undelete' facility (I am assuming that the files were deleted, or else how would the files be on the disk?) The other way is fairly straightforward (once you get used to it). Again, assuming you have Copy ][+, the first step is to do a disk map. Print this. Now look through the disk with the disk editor, in the non-marked sectors (if the files were in the marked sectors, they've been overwritten). What you are searching for is something like this: 12 0E 12 0D 12 0C 12 0B 12 0A 12 10 12 09 12 08 12 07 12 06 12 05 etc. This is known as a "Track Sector map" (T/S map). The T/S map tells DOS where your file is stored at on the disk. In this case, the T/S map is undoubtably stored on track 12, sector 0F (most of the time, T/S maps are stored on sector 0F of a track). The first sector of the file is on track 12 0E, the next is on sector 0D, etc. Print this. (track 11) by searching for the end of the catalog (start at sector 0F and ****** BACK UP YOUR DISK BEFORE DOING ANY MORE!! ***** Edit your catalog track ( track 12) Find the appropriate sector by working backwards till you find a blank space.) Put in a name. Look at the other names, and you'll see there is a hexadecimal code for Binary, Text and Applesoft files. Put in the appropriate one (if you know what it is). If you don't have the foggiest idea, then Binary is probably your best bet. Now count the sectors (from the T/S list) and plug it into the catalog. You are done! Try to run it... Patrick Ryan D7314@UWAVM.BITNET
binder@nacho.DEC.COM ("Exit, pursued by a bear") (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? > One way is to use Copy ][+ or some such utility and use the 'undelete' > facility (I am assuming that the files were deleted, or else how would the > files be on the disk?) The files would have been on the disk, but not necessarily in the normal way. There are at least two simple ways I know of, to use things that won't show up in the catalog. Both ways are usually applied to disks that come without copy protection, to slow down pirates just a little. 1. The files could be there in a specific place on the disk that a named program knows about and can access directly via RWTS. If the disk is like this, then FID will miss copying the "hidden" files because it copies by catalog filenames. The Diversi-DOS master disk is made in this way, and the docs state explicitly that you must use COPYA to make backups. 2. The files could be in the catalog with nonprinting characters in the file names (^H etc) to cause the names not to be displayed. I have seen game disks like this, with the catalog actually jimmied up to put a "USE COPYA" warning on the screen. There may be other tricks as well. Cheers, Dick Binder (The Stainless Steel Rat) UUCP: { decvax, allegra, ucbvax... }!decwrl!asd.dec.com!binder ARPA: binder%asd.DEC@decwrl.ARPA
ilacqua@bucsb.bu.edu.UUCP (:-) (10/14/86)
In article <8610100029.AA19813@ucbvax.Berkeley.EDU> D7314@UWAVM.BITNET writes: >Date: Thu, 9 Oct 86 16:11 PDT >From: Patrick Ryan <D7314@UWAVM> >Subject: Re: Files not on Catalog >To: Apple Mailing list <INFO-APPLE@BRL.ARPA> > >> 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? >This is known as a "Track Sector map" (T/S map). The T/S map tells DOS >where your file is stored at on the disk. In this case, the T/S map is >undoubtably stored on track 12, sector 0F (most of the time, T/S maps are >stored on sector 0F of a track). The first sector of the file is on track >12 0E, the next is on sector 0D, etc. Print this. >(track 11) by searching for the end of the catalog >Edit your catalog track ( track 12) Find the appropriate sector by The catalog track is 11 (hex). the T/S list is on track 11 (hex) sector 00 (hex). -- +--------------------------------------------------------------------+ | I never make mistakes. I thought I did once, but I was wrong. | |UUCP: ...!harvard!bu-cs!bucsb!ilacqua | |ARPANET: ilacqua@bucsb.bu.edu | |CSNET: ilacqua%bucsb@bu-cs BITNET: engemnc@bostonu | +--------------------------------------------------------------------+
binder@asd.DEC.COM ("Exit, pursued by a bear") (10/15/86)
> The catalog track is 11 (hex). the T/S list is on track 11 > (hex) sector 00 (hex). > -- > +--------------------------------------------------------------------+ > | I never make mistakes. I thought I did once, but I was wrong. | > |UUCP: ...!harvard!bu-cs!bucsb!ilacqua | > |ARPANET: ilacqua@bucsb.bu.edu | > |CSNET: ilacqua%bucsb@bu-cs BITNET: engemnc@bostonu | > +--------------------------------------------------------------------+ Oops, you've just made your first mistake. The correct names and locations for the components of the Apple DOS cataloguing system are these: CATALOG: Occupies track 11-hex/17-decimal, except sector 0. Begins at sector F-hex/15-decimal. Capable of recording 105 files, 7 in each sector. Each non-empty sector contains a pointer to the next, with the last pointer being zeroes. Successive sectors are each one less, numerically, so that the first is at T11-SF, the second is at T11-SE, and so on. VTOC: (Volume Table Of Contents) Occupies track 11-hex/17-decimal, sector 0. Records DOS version, allocation direction, disk size. Keeps track of used sectors via a bit map. T/S List: (Track/Sector List) Occupies the first sector of each file. Lists the locations of successive data sectors of that file. If a file exceeds a certain size, it may contain more than one T/S list; the second will be in the middle of the file, after the data sectors listed in the first T/S list. The standard method of allocation on a fresh disk is to start at track 12-hex/18-decimal, sector F-hex/15-decimal, and allocate inward toward higher track numbers until the end of the disk is reached, and then to begin outward allocation at track 10-hex/16-decimal. The idea is that the catalog information will be at the center of the seek range, thereby minimizing the overall amount of seeking needed to refer to it. To retrieve "hidden" files, you really must have a disk editing utility. The one I use is part of the ANIX package. Cheers, Dick Binder (The Stainless Steel Rat) DEC Enet: ASD::BINDER UUCP: { decvax, allegra, ucbvax... }!decwrl!asd.dec.com!binder ARPA: binder%asd.DEC@decwrl.ARPA