Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!swrinde!kent From: kent@swrinde.nde.swri.edu (Kent D. Polk) Newsgroups: comp.sys.amiga.misc Subject: Re: File Recovery on an 80 MB partition Keywords: File, HD Message-ID: <1489@swrinde.nde.swri.edu> Date: 20 Feb 91 04:04:34 GMT References: <1276@swrinde.nde.swri.edu> <19122@cbmvax.commodore.com> Sender: news@swrinde.nde.swri.edu Organization: Southwest Research Institute, San Antonio, Texas Lines: 60 In article <19122@cbmvax.commodore.com> daveh@cbmvax.commodore.com (Dave Haynie) writes: >In article <1276@swrinde.nde.swri.edu> kent@swrinde.nde.swri.edu (Kent D. Polk) writes: > >>Question: is there a utility (like the old Diskzap) that can work on an >>80 MB partition? > >I use DiskX for DiskSalv development. It can edit tracks on any FFS or SFS >disk I have tried to date. >>If so, can I follow a thread & designate it to be moved to a new file - fsdb >>fashion? Or any fashion really? I can even get by with most of the data. > >Problem is, the only thread under FFS is in the file header. Well, not all [...] >by subsequent extension block pointers, to the next extension block, and so >on. I don't know of any easy way to get DiskX to do this; you can imagine >what the "difficult" way involves. We pulled up DiskX 2.2 (Steve Tibbett) and located about 400 of the desired blocks so far - by hand. DiskX can copy, block-by-block from one place to another, so we started trying to do so. Unfortunately, DiskX only knows how to save 488 byte blocks & gets confused when reading from 512 byte blocks. >I have been thinking of doing something with loose extension blocks in future >versions of DiskSalv. Well, perhaps a little more than just thinking about >it.... Believe me, it would be much appreciated. Back to the the task at hand: We are currently following two paths: a program to dump a list of block numbers (specified by a file), and one to dump a range of blocks to a file. Then a filter to search for the patterns and extract the data to another file. I would like to track the extension blocks, but either DiskX had trouble following them, or we did. (Still have 3MB more to go too). Right now we are trying to figure out how to 'convert' a trackdisk test program to work with the 2091. Hopefully will have something working soon. BTW, where is this stuff documented? I've gotten bits and pieces from AmigaMail, RKM's, examples on Fish Disks. Can we just substitute the device, unit num, etc. and use "trackdisk" calls? Do you happen to have: 1) an example of how to find the device & unit number from the system lists, given a partition name...? I know how to determine the numbers by hand - just wanted to specify the partition name to make it a bit more general. 2) an example of tracking the extension blocks (given a known one)? (though I think we have this one pretty much figured out) -------------------------------------- This has been a very educational experience. Provided one of those golden opportunities to learn some of this stuff :^( "Warming up for gpib.device" Polk Internet : kent@swrinde.nde.swri.edu UUCP : $ {cs.utexas.edu, gatech!petro, sun!texsun}!swrinde!kent