meier%isl@AMSAA.ARPA (03/08/84)
Jesse, DUU and DU2 are probably what I can use. How can I get a copy of them? My BIOS also traps bad sector errors, but at least it would prevent me from losing all the information on a disk. It would allow me to mark the sectors as bad in the directory. (and thus prevent cp/m from trying to use them) Bob (shasta!isl!meier@amsaa.arpa)
ABN.ISCAMS%usc-isid@sri-unix.UUCP (03/09/84)
DUU and DU are at SIMTEL20 via anonymous FTP (I think DUU is in the SIGM files somewhere, and DU under disk utilities). FINDBAD, which is supposed to find and lock out bad sectors (by storing them in a file called BAD or something like that) is also out there -- however I find it does not catch all the errors, since I can run FINDBAD and still get BDOS errors. Donno why. If you need help FTPing from SIMTEL20, yell. Regards, David Kirschbaum Toad Hall (ABN.ISCAMS@USC-ISID)
Eaton.HFED@AMSAA.ARPA (03/14/84)
DUU and DU2 (with more features) are indeed excellent disk editors. There is however one slight problem when dealing with disks with bad sectors. My BIOS and I assume most BIOS' trap errors and will not return the data to DUU or DU2 if one is detected. This leaves the contents of the previous read in DUU's buffer. I wrote quick and dirty DDT routines to turn off error detection while attemting to repair bad sectors and then reenable error detection when I'm done. NEVER! "That's NEVER EVER try fixing a bad track by doing: read.. write.. increment.. loop. Fix those nasty little sectors one at a time "manually". I completeletely destroyed a directory by doing the afforementioned "never ever". The error handling/reporting by those programs "should" abort loops and return error messages to the user. Jesse (who knows more than one way to destroy a disk)