********************************************************************** *** *** *** RECLAIM (Version_2 -- June 1993) *** *** ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ *** *** *** *** ( renders useable the 2 clusters that *** *** TOS "loses" on formatted floppies ) *** *** *** *** ( Freeware by W. Alan B. Evans [wabe@ukc.ac.uk] ) *** *** *** *** ( May NOT be distributed without accompanying RECLAIM.TXT *** *** NOR commercially distributed without Author's permission ) *** *** *** ********************************************************************** For some reason best known to Atari, TOS "wastes" 4 sectors (or 2 1024 byte clusters) of formatted disk space. For example, with the standard double-sided Atari format we have 1 bootsector, 2 sets of fats each 5 sectors long and a root directory which is 7 sectors long. The disk is formatted to 80 9-sector tracks on both sides i.e. 1440 512-byte sectors in all. Since the "disk management" accounts for 18 of these, one might reasonably expect there would be 1422 left over to hold data i.e. we'd expect 711 clusters of data. But NO! - as is well-known there's only 709 clusters available for data. What has TOS done with the other 2? I'm sure I don't know - I've never seen any explanation for this documented! But there _MAY_ be a good reason - and, IN CASE THERE IS, and in any case as this software is FREEWARE, I give NO GUARANTEES WHATSOEVER for any consequences that might arise out of using RECLAIM. Therefore, it would be wise to be wary (esp. with valuable data) until one has gained full confidence in the usage of RECLAIM. All I can say is that I have personally been using RECLAIM for some while with no adverse-effects. The idea for RECLAIM is originally in the RDY sourcecode of Mark Williams Co.'s "RDY" ramdisk utility. Whilst upgrading the latter recently (Version_4 of RDE is now available at a.a.) I noticed that a little trick which the author of RDY called a CLUSTERHACK allowed the ramdisk to reclaim these 2 lost clusters back from TOS. Basically the strategy is exceedingly simple viz. alter the boot parameter block info to signal a total sector number which is 4 more than actually exists and to MARKBAD the last two FAT clusters. It occurred to me that this might also work on Floppies and, indeed, it seems to. However I know of no formatter program that will format floppies in this "RECLAIMed" state. You can use a disk editor ( DISK DOCTOR, KNIFEST etc. ) to do the alterations. However, altering the format with a disk utility involves some intricate calculations to locate the last two fats' positions etc. etc. and a small error could cause loss of data. RECLAIM.TOS simplifies & speeds up this task. At the prompt you simply insert a normally formatted disk and RECLAIM will do these conversions and modify the disk so that you will end up with 2 kbytes more of free space on it. Of course, it checks to see if the disk has previously been altered and, in that event, will tell you and alter nothing. Note also that disks containing data can also have their missing sectors RECLAIMed - with no harm to the data. Beware though of utilities that wipe out the entire fat tables (e.g. DISK TOOL ( DT.TTP ) with option "-w" ). Most (all?) utilities that do this ignore the possible presence of MARKED BAD clusters. Hence using DT.TTP or similar will wipe out the MARKBAD marks and thereafter the disk would signal to TOS that it has valid sectors that, in fact, do not exist. In the same vein, if you use a Disk Utility sector editor (such as DISKDOC) you should not try to read the last four sectors declared by the BBPB (that don't really exist) else you may hear "grating" sounds from your diskdrive before TOS complains. If one uses the SEEKUP patch (by Martin Osieka) to cure the "grating" diskdrive sounds, which is a bug in TOS 2.06 when fitted to older ST's without HD-drives, one finds that trying to read nonexistent sectors results in the default values of whatever SEEKUP alters (FLOPRATE etc.) being re-established - so, if you must do this, be prepared to run SEEKUP again to keep your diskdrive "harmonious". After converting a disk with RECLAIM, one should strictly tell TOS that the media has been changed. RECLAIM _does_ do this though I see no great reason to, since all we've released are two clusters at the high end - so that the worse that can happen is that a file that should fit on your (enlarged) disk might actually fail to do so as TOS is unaware of the 2 extra clusters. I know of no other pitfalls....(perhaps someone can enlighten me) but, meantime, good luck RECLAIMing what's rightfully yours! By the way, I've used the ICE packer to pack RECLAIM.TOS which "just" gets it below 2 clusters in size. How appropriate! - take a full floppy, apply RECLAIM to it, and your gained space is just enough to store RECLAIM.TOS!! P.S.: The last sentence applied before I added a check to see if there was any data on the disk - and, ONLY IF THERE IS NO DATA, RECLAIM gives you the option of changing the No. of Fat Sectors (FSIZE) and No. of Root directory sectors (ROOT) the default being NO CHANGE. As is well-realised 5 FAT-sectors is too much to cover all the usual Double sided formats (3 is sufficient) - and so by trimming these down there is further scope for obtaining more DATA sectors. BUT, be careful here, TOS sometimes fails to recognise a media change, so if you keep swapping floppies with different management structures, it _MAY_ get confused. So my advice to beginners is to KEEP THE DEFAULT VALUES (FSIZE=5 and ROOT=7 usually) and just be content to RECLAIM the 2 lost clusters. So the program now is ~2800 bytes (ICE- packed) and calls itself RECLAIM V_2 ( V_1 was never distributed). W. Alan B. Evans. (June 93). ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~