Re: Re: Corrupted NB
- To: mathgroup at smc.vnet.net
- Subject: [mg14494] Re: [mg14419] Re: Corrupted NB
- From: Garrett Tim Sos <gts at mindspring.com>
- Date: Fri, 23 Oct 1998 20:59:13 -0400
- References: <70dd69$234@smc.vnet.net> <199810210732.DAA14783@smc.vnet.net.>
- Sender: owner-wri-mathgroup at wolfram.com
Maybe this idea should also apply to the preferences files that still (version 3.0.1.1x) become corrupted (on the Mac, atleast) so often that I no longer try to change from the factory default preferences. I logged a call to WRI on a different issue and asked about the preferences file corruption problem and got the answer that it was "the computer's fault" implying that they did not feel it needed to be fixed. Maybe he was just having a bad day but sometimes it is hard to like WRI. I have been using Mathemetica since Version 1.1. It is a wonderfully complex creation but 3.0's habit of destroying user INPUT (preferances, notebooks and strange corruption of cells) is dreadful. Tim Joe Gwinn wrote: > > I have also had this problem, but I have never succeeded in fixing a > damaged notebook. The problem has always happened when Mathematica > crashed while saving the notebook Now I periodically make a no-output > backup copy called "<whatever>.nb short" so I don't lose everything > when Mathematica crashes. > > This kind of destroy-file-on-save behaviour was very common in early > (mainframe and mini) computer software, and subsequently in early PC > and Mac software, but is now mostly a thing of the bad old days. The > standard solution is to do file saves in such a way that there is never > a window of vulnerability, where a computer crash (for whatever reason) > could leave one with only a corrupted file. > > The method? Simple. One 1970s variant: Open a temporary file and > write the new version of the document into it. If successful, rename > the old file with a temporary name, and then rename the just-written > temporary file (containing the new document) to be the updated file. > Delete the old file with the temporary name. No matter when the crash, > there is at least one good file surviving, perhaps with a temporary > name. Temporary files are not deleted on a crash, so this can work. > > This does require that one have scratch disk space sufficient to carry > an extra copy of the file, but this is generally true, especially in > this day of multi-gigabyte disks. More to the point, this method was > used even when disks were tiny, so one can conclude that users would > rather have bulletproof file saves than the extra disk space. > > Joe Gwinn > > In article <70dd69$234 at smc.vnet.net>, "Kevin J. McCann" > <kevinmccann at Home.com> wrote: > > > I have a NB which when I try to run it tells me that there was a syntax > > error. The popup goes on to say that I can open it as a text file, > > etc. Is there a way to recover from this. The problem appears to have > > been generated when Mathematica crashed. > > > > Kevin
- References:
- Re: Corrupted NB
- From: gwinn@ma.ultranet.com (Joe Gwinn)
- Re: Corrupted NB