cramer@kontron.UUCP (Clayton Cramer) (05/15/86)
We've found what looks like a severe bug with the PC-DOS 3.1 DEL command --
watch out!
One of the engineers working for me typed:
DEL A.O
and was asked "Are you sure (Y/N)?"
Not being thoroughly familiar with PC-DOS, he didn't realize that this
prompt is put out when you say "DEL *.*", so he said "y<return>" and
the entire directory was cleared out. A little experiementation found
that DEL followed by ANY single filename caused it to assume that we had
typed "DEL *.*".
ERASE works correctly -- only DEL (which should be equivalent) fails.
Clayton E. Cramercramer@kontron.UUCP (Clayton Cramer) (05/15/86)
> We've found what looks like a severe bug with the PC-DOS 3.1 DEL command -- > watch out! > > One of the engineers working for me typed: > > DEL A.O > > and was asked "Are you sure (Y/N)?" > > Not being thoroughly familiar with PC-DOS, he didn't realize that this > prompt is put out when you say "DEL *.*", so he said "y<return>" and > the entire directory was cleared out. A little experiementation found > that DEL followed by ANY single filename caused it to assume that we had > typed "DEL *.*". > > ERASE works correctly -- only DEL (which should be equivalent) fails. > > Clayton E. Cramer But DEL doesn't fail everytime. Some quirk, perhaps, of the particular order of files in the directory? Clayton E. Cramer
kpk@gitpyr.UUCP (Kevin P. Kleinfelter) (05/16/86)
In article <785@kontron.UUCP>, cramer@kontron.UUCP (Clayton Cramer) writes: > ... A little experiementation found > that DEL followed by ANY single filename caused it to assume that we had > typed "DEL *.*". > > ERASE works correctly -- only DEL (which should be equivalent) fails. > > Clayton E. Cramer I have been using "del" for months with no (observed) problem. Has anyone else noticed this problem? (I can't believe that in 5 months of use I have never deleted a single file!) I NEVER use "erase" because it means typing extra characters.
kpk@gitpyr.UUCP (Kevin P. Kleinfelter) (05/17/86)
In article <787@kontron.UUCP>, cramer@kontron.UUCP (Clayton Cramer) writes: > > We've found what looks like a severe bug with the PC-DOS 3.1 DEL command -- > > watch out! > > > > One of the engineers working for me typed: > > > > DEL A.O > > > > and was asked "Are you sure (Y/N)?" > > > > Not being thoroughly familiar with PC-DOS, he didn't realize that this > > prompt is put out when you say "DEL *.*", so he said "y<return>" and > > the entire directory was cleared out. A little experiementation found > > that DEL followed by ANY single filename caused it to assume that we had > > typed "DEL *.*". > > > > But DEL doesn't fail everytime. Some quirk, perhaps, of the particular > order of files in the directory? > Or perhaps the directory itself is messed-up. I would like to know if this can be repeated after using CHKDISK.
bc@cyb-eng.UUCP (Bill Crews) (05/18/86)
> ERASE works correctly -- only DEL (which should be equivalent) fails. > > Clayton E. Cramer Lest others be misled, I must respond. ERASE and DEL each result in the SAME CODE being executed within COMMAND.COM. DEL has worked correctly for me and many others for many moons now. I suspect the problem might have had to do with some of DOS memory getting scribbled on, causing the DEL to work incorrectly. I bet the ERASE command was tried and worked successfully after something changed -- perhaps reboot. Was DEL then retried? I wonder. -- - bc - ..!{seismo,topaz,gatech,nbires,ihnp4}!ut-sally!cyb-eng!bc (512) 835-2266
cramer@kontron.UUCP (05/20/86)
> In article <787@kontron.UUCP>, cramer@kontron.UUCP (Clayton Cramer) writes: > > > We've found what looks like a severe bug with the PC-DOS 3.1 DEL command -- > > > watch out! > > > > > > One of the engineers working for me typed: > > > > > > DEL A.O > > > > > > and was asked "Are you sure (Y/N)?" > > > > > > Not being thoroughly familiar with PC-DOS, he didn't realize that this > > > prompt is put out when you say "DEL *.*", so he said "y<return>" and > > > the entire directory was cleared out. A little experiementation found > > > that DEL followed by ANY single filename caused it to assume that we had > > > typed "DEL *.*". > > > > > > > But DEL doesn't fail everytime. Some quirk, perhaps, of the particular > > order of files in the directory? > > > Or perhaps the directory itself is messed-up. I would like to know if > this can be repeated after using CHKDISK. CHKDSK ran without complaint -- I can't make DEL fail anymore. (Cringe! I get real nervous about problems like this.) Clayton E. Cramer
cramer@kontron.UUCP (Clayton Cramer) (05/21/86)
> > ERASE works correctly -- only DEL (which should be equivalent) fails. > > > > Clayton E. Cramer > > Lest others be misled, I must respond. ERASE and DEL each result in the > SAME CODE being executed within COMMAND.COM. DEL has worked correctly > for me and many others for many moons now. > > I suspect the problem might have had to do with some of DOS memory getting > scribbled on, causing the DEL to work incorrectly. I bet the ERASE command > was tried and worked successfully after something changed -- perhaps reboot. > > Was DEL then retried? I wonder. DEL now works reliably -- you probably have described the problem correctly. (I sure wish the PC had memory protect -- I have no idea what program I ran could have trashed us.) Clayton E. Cramer
timothym@tekigm2.UUCP (05/21/86)
Hi, I have been reading for some time the comments about DEL A.O responding with a ARE YOU SURE? prompt. What it looks like to me is the original poster had a directory named A.O, and the are you sure prompt was justified. And after the delet was completed, all the files in that directory were wiped. Of course, had they the Norton programs they could have recovered the lost files without incident. My opinion. -- Tim Margeson (206)253-5240 tektronix!tekigm2!timothym @@ 'Who said that?' PO Box 3500 d/s C1-937 Vancouver, WA. 98665
kim@mips.UUCP (05/25/86)
>> Lest others be misled, I must respond. ERASE and DEL each result in the >> SAME CODE being executed within COMMAND.COM. >> >> I suspect the problem might have had to do with some of DOS memory getting >> scribbled on, causing the DEL to work incorrectly. I bet the ERASE command >> was tried and worked successfully after something changed -- perhaps reboot. > > DEL now works reliably -- you probably have described the problem correctly. > (I sure wish the PC had memory protect -- I have no idea what program I > ran could have trashed us.) Hmmmm ... I don't have any "internals" experience with DOS 3.x, but in all previous releases (1.x, 2.x) the code for the built-in commands like dir, erase/del, etc. have resided in the *transient* part of COMMAND.COM, which is relocated to the high end of memory. Whenever control is passed/returned to COMMAND.COM, it (the *non-transient* part, which is in low core) runs a checksum on the transient part. If the actual checksum is different that what is expected, it causes a reload of COMMAND.COM from disk before prompting the user for the next command. I agree that *something* is getting trashed by someone, but I be surprised if it were the ERASE/DEL code itself (unless, of course 3.x is structuraly different that 2.x). /kim -- UUCP: {decvax,ucbvax,ihnp4}!decwrl!mips!kim DDD: 408-720-1700 x231 USPS: MIPS Computer Systems Inc, 930 E. Arques Av, Sunnyvale, CA 94086 CIS: 76535,25