Re: [9fans] [OT] interesting hardware project for gsoc
Alexander Sychev wrote: In the Russian army: Sgt.: Who is a painter here? Soldier: I'm the painter. Sgt.: Well, take this axe and draw me a stack of firewood in the morning. That one sounds like it was written by Milligan. Martin
Re: [9fans] readme for THNX
ron minnich wrote: The intent is that this USB disk is a starting point for your machine. We did not set up the usb stick with all the friendly automagic /etc/rc.d/init.d stuff because that is all so slow and ugly. The intent is that you start from this simple base and extend as much as needed for your platform. It does not take much to customize it. I think the talk today left people confused a bit, and I'm sorry if it did. I think I went too fast. When you boot and get the grub prompt grub enter configflie /boot/grub/menu.lst and hit return. And if you know how to make it stop asking this, let me know. Have you tried this: cd /boot/grub mv menu.lst grub.conf ln -s grub.conf menu.lst (This will make it look like it does on my Red Hat system. I think the grub.conf name is built in to grub...) I was sorry not to be able to make it to the conference, especially as I'm close by - too busy at work this week. Maybe next time. Martin
Re: [9fans] Venti flash device?
David Leimbach wrote: 120GB SATA or IDE flash drive. http://www.adtron.com/newsroom/25fb-Solid-State-Disk.html Wish I knew where to get these. None of the standard places I check seem to have em. Why don't you ask them? (there's an email address on the web page.) I suspect they are expensive. Martin
Re: [9fans] serial reboot boxes
Russ, Quality solid state AC relays may be obtained at reasonable prices from: Digikey (www.digikey.com) Mouser (www.mouser.com) Be careful though - some of them may be thyristor (half wave) output rather than Triac (full wave) output. I'd be happy to assist in selecting a suitable component if it would help. Martin (for whom building hardware is yet another activity to occupy his Copious Free Time.)
Re: [9fans] Threadcreate() failure value?
what if your create failed due to some other process having the process leak, and you'd like your process, which has done nothing wrong, to get out of the mess cleanly? One of the problems is that the program that finds itself unable to proceed for lack of resources may not be able to recover because it needs resources to run the recovery mechanism. This was dicussed a long time ago wrt memory allocation for Modula 3. See, for example: http://www.elegosoft.com/pm3/intro/questions/new.html (I'm sure that somewhere I've seen a more basic description of why handling out-of-memory conditions is diffucult, but I can't find it right now.) I'd be the first to admit that this is a somewhat different case because M3 relies heavily on dynamic memory allocation and garbage collection, but I think that in general terms the issues are the same. Martin
Re: [9fans] Xen for Windows(Was:vmware 5.0)
See the following paper (by a colleague) for more than you wanted to know about the development of VM. It was, in the beginning, a skunk works project. http://pucc.Princeton.EDU/~melinda/25paper.pdf Martin Brantley Coile wrote: i too am both curious as to the motivations for VM and completely open minded with no preconceived notions about VM. except my aversion to hype. but hype is independent from the quality of an idea. i was asking Friday here at work, what are the modivations behind VM? the only answers that were offered were variations on the ability to rent someone a machine that has root access without having as many machines are renters. the earliest VM i know of is VM/CMS, from IBM, which is still used today. its purpose was to provide early timesharing, and was also used to debug MVS. so those are two motivation, although Xen can't be used for debugging OSes since it's a paravirtual machine. i don't think VMware would be too good either because it rewrites parts of your code. maybe that's not a problem in practice. maybe Ron can give us insight into the motivations for using VM.
Re: [9fans] Absent friends of Boyd list so far ...
Likewise for me. I'm sure he wouldn't know me from Adam, but I always enjoyed reading his take on things. Same goes for me. Please add my name to the list. Martin
Re: [9fans] crypto question
Done to please the export controllers, methinks. From the 2nd edition ENCRYPT(2) man page: BUGS The source is not included in the public distributions. The implementation is broken in a way that makes it unsuitable for anything but authentication. Martin Tim Newsham wrote: Hi, I noticed that the libc function encrypt() uses some non-standard form of cipher chaining. In the normal case one byte from the previous block is reencrypted with 7 bytes from the new block. Additionally there is no initialization vector used. This chaining is not very strong (only slightly better than using ECB mode). In particular: - common prefixes will encrypt the same way. - large common sequences within the middle or end of the data have a reasonable chance of encrypting the same way (2^-8 chance of rejoining at each encryption boundary). These weaknesses could open the way for attacks on the code where encrypt() is used. I was looking over the p9sk1 authentication and didn't notice any obvious attacks, but I'm not particularly good at cryptography (the fact that the challenge has to be matched in tickets encrypted by two different keys offers some protection against splicing). Is there any reason this scheme was chosen over more traditional chaining modes? Tim Newsham http://www.lava.net/~newsham/
