chrisb@hubcap.clemson.edu (Chris Behrens) (01/29/91)
Is there a way to access these ?? Or is there a way to change them ?? Add them to older diskettes (pre-4.0) ?? Or not have them on the diskettes at all, or delete them once they are there ?? Thank You. Chris Behrens. ChrisB@Hubcap.Clemson.Edu
paul@nuchat.sccsi.com (Paul Hutmacher) (03/05/91)
In article <12818@hubcap.clemson.edu> chrisb@hubcap.clemson.edu (Chris Behrens) writes: >Is there a way to access these ?? Or is there a way to change them ?? And while we're at it, what the hell are they for? -- Paul Hutmacher | paul@nuchat.sccsi.com P.O. Box 66046 | {uhnix1, uunet}!nuchat!paul Houston, TX 77266 | paul%nuchat.uucp@uhnix1.uh.edu
mir@opera.chorus.fr (Adam Mirowski) (03/05/91)
In article <1991Mar5.033219.369@nuchat.sccsi.com>, paul@nuchat.sccsi.com (Paul Hutmacher) writes: %% In article <12818@hubcap.clemson.edu> chrisb@hubcap.clemson.edu (Chris %% Behrens) writes: %% >Is there a way to access these ?? Or is there a way to change them ?? %% %% And while we're at it, what the hell are they for? I see 2 purposes: - copy protection (upon installation an application stores the disk SN) - diskette identification (although the Disk Change signal could be enough). -- Adam Mirowski, mir@chorus.fr (FRANCE), tel. +33 (1) 30-64-82-00 or 74 Chorus systemes, 6, av.Gustave Eiffel, 78182 Saint-Quentin-en-Yvelines CEDEX
tmkk@uiuc.edu (Scott Coleman) (03/05/91)
In article <8105@chorus.fr> mir@opera.chorus.fr (Adam Mirowski) writes: >In article <1991Mar5.033219.369@nuchat.sccsi.com>, paul@nuchat.sccsi.com (Paul Hutmacher) writes: >%% >%% And while we're at it, what the hell are [Volume Serial Numbers] for? >I see 2 purposes: >- copy protection (upon installation an application stores the disk SN) >- diskette identification (although the Disk Change signal could be enough). They're also ideal for cataloging: Anyone who downloads as much stuff as I do from anonymous ftp sites (and pack-rats it away ;-) needs to be able to keep track of the hundreds of floppies. It's a simple matter to write a program which reads the directory and serial number from the disk and stores them in a master database. As long as each disk is labelled with its serial number, finding those sources to Xtank that you downloaded in the summer of 1989 is a snap!
gtoye@supernet.dallas.haus.com (Gene Toye) (03/06/91)
mir@opera.chorus.fr (Adam Mirowski) writes: >In article <1991Mar5.033219.369@nuchat.sccsi.com>, paul@nuchat.sccsi.com (Paul Hutmacher) writes: >%% In article <12818@hubcap.clemson.edu> chrisb@hubcap.clemson.edu (Chris >%% Behrens) writes: >%% >Is there a way to access these ?? Or is there a way to change them ?? >%% >%% And while we're at it, what the hell are they for? My understanding is that they came about mostly for OS/2 and were added to DOS 4.0 for compatability. They are needed in OS/2 to deal with multitasking since you might remove the diskette while another program was using it. OS/2 couldn't ask for the disk by the "normal" LABEL since uniqueness is not guaranteed. -- Gene Toye: Harris Adacom Corporation / 16001 Dallas Pkwy. / Dallas, TX 75248 Internet: gtoye@supernet.haus.com or gtoye@supernet.lonestar.org Usenet: uunet!{iex,ntvax}!supernet!gtoye DISCLAIMER: My employer never knows what I am going to say next.
larry@palan.uucp (Larry Strickland) (03/06/91)
In article <1991Mar5.033219.369@nuchat.sccsi.com> paul@nuchat.sccsi.com (Paul Hutmacher) writes: >In article <12818@hubcap.clemson.edu> chrisb@hubcap.clemson.edu (Chris Behrens) writes: >>Is there a way to access these ?? Or is there a way to change them ?? > >And while we're at it, what the hell are they for? I'm still not sure what they are for, but they are stored in the boot sector (in the extended portion of the configuration section) in ASCII! If you have TurboC (or probably anything else), you can use the absolute disk read to read the first sector on the disk and you will find it there. I can change it with debug and there seems to be no effect. Of course, this doesn't work on extended (>32M) DOS partitions. -larry
walters@iccgcc.decnet.ab.com (03/07/91)
In article <1991Mar5.033219.369@nuchat.sccsi.com>, paul@nuchat.sccsi.com (Paul Hutmacher) writes: > In article <12818@hubcap.clemson.edu> chrisb@hubcap.clemson.edu (Chris Behrens) writes: >>Is there a way to access these ?? Or is there a way to change them ?? > Here is how you get/set the volume serial number. Others have already posted with regard to the serial numbers usefullness. Hope this helps!!!! INT 21 - DOS 4.0 internal AH = 69h AL = subfunction 00h get serial number 01h set serial number BL = drive (0=default, 1=A, 2=B, etc) DS:DX -> disk info (see below) Return: CF set on error AX = error code (see AH=59h) CF clear if successful AX destroyed (AL = 00h) buffer filled with appropriate values from extended BPB (AL = 01h) extended BPB on disk set to values from buffer Notes: does not generate a critical error; all errors are returned in AX error 0005h given if no extended BPB on disk does not work on network drives (error 0001h) buffer after first two bytes is exact copy of bytes 27h thru 3Dh of extended BPB on disk Format of disk info: Offset Size Description 00h WORD info level (zero) 02h DWORD disk serial number (binary) 06h 11 BYTEs volume label or "NO NAME " if none present 11h 8 BYTEs (AL=00h only) filesystem type--string "FAT12 " or "FAT16 " Tom No Sig Yet