on Thu, Nov 30, 2000 at 10:46:31PM +0100, Thomas Halahan (tom@halahan.com) wrote: > Adam & Karsten, > > thanks very much for your postings. i am a fool for not backing up > better - i suppose i was waiting to buy a CD writer but didn't want > to spend. > > anyway hints from your emails gave me enough to go on. i ran fsck to > repair. you also mentioned libraries which i looked into, and sure > enough the contents to lib had been moved! > > so i'm sorry to say i was obviously wrong - i had not deleted the > root (i don't think anyway) but somehow the essential system > libraries had been moved and hence 'ls' and other command did not > work. > > i would not have been able to do this without your promt help. thank > you very much. WRT libs. For most programs, you're basically hosed if you manage to shitcan them, which can happen more easily than you might think. E.g.: there's a reason libraries are maintained as links to the actual files. $ rm oldlib; cp newlib oldlib ...fails if 'cp' requires lib. I believe 'mv' is implemented as a 'rm; cp', effectively, though I want to check sources. $ ln -sf newlib lib ...safely overwrites the symbolic link previously pointing to oldlib. Which is how libraries are updated on an active system. It's also helpful to keep a statically linked shell, such as sash, the stand-alone shell, around. It can do things when your libs are trashed (or other system binaries are compromised, e.g.: by a cracker). You can also, as I indicated, do a fair bit with whatever command interpreter you have currently loaded. Once a program is in memory, it stays there. You can blow away your system and still have a running shell [1]. Can't do much, unless you can get a filesystem mounted or similar, but you're still active. Understanding the workings of this can be helpful if you find yourself in dire straits. [1] I won't reveal how I came by this information. -- Karsten M. Self <kmself@ix.netcom.com> http://www.netcom.com/~kmself Evangelist, Zelerate, Inc. http://www.zelerate.org What part of "Gestalt" don't you understand? There is no K5 cabal http://gestalt-system.sourceforge.net/ http://www.kuro5hin.org
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