[9fans] venti
hi, i noticed something odd with venti and i am just trying to see if this is an issue and if this needs to be addressed. i think, by default, plan9 installation sets localhost as the address for venti in plan9.ini. but at some point i wanted venti to announce any (*) address. for some reason, i simply started venti/venti -a 'tcp!*!17034' to make it so. after this, i did vac from another machine and it archived data. after sometime, i realized i may be running venti on the same venti data area twice. when i did 'ps', it looked like that. then i rebooted the machine and then tried 'dumpvacroots.new' command (from contrib). i noticed that venti arena was corrupted. this is what i remember and if required i can try to reproduce the issue. the question i have is, is there any protection that prevents someone from doing this accidentally? something like the last active venti arena is marked 'IN_USE' so that if another instance of venti is started (with read-write access), it can check for this? i agree user has to be careful but given that venti archive is so critical, we should avoid any accidental damage. please pass your views. thanks dharani
Re: [9fans] venti
i noticed something odd with venti and i am just trying to see if this is an issue and if this needs to be addressed. i think, by default, plan9 installation sets localhost as the address for venti in plan9.ini. but at some point i wanted venti to announce any (*) address. for some reason, i simply started venti/venti -a 'tcp!*!17034' to make it so. after this, i did vac from another machine and it archived data. after sometime, i realized i may be running venti on the same venti data area twice. when i did 'ps', it looked like that. then i rebooted the machine and then tried 'dumpvacroots.new' command (from contrib). i noticed that venti arena was corrupted. this is what i remember and if required i can try to reproduce the issue. the question i have is, is there any protection that prevents someone from doing this accidentally? something like the last active venti arena is marked 'IN_USE' so that if another instance of venti is started (with read-write access), it can check for this? i agree user has to be careful but given that venti archive is so critical, we should avoid any accidental damage. Hmm. Running two ventis on the same data is, of course, bad. It's also something I haven't seen happen before. A check could be put in by having venti put some sort of lock somewhere on the disk. But that would lead to problems if venti doesn't shut down properly: venti would be gone but the lock would still be there. You run the risk of not being able to boot your machine. I think you should just learn to be careful. Sape
Re: [9fans] venti
Hmm. Running two ventis on the same data is, of course, bad. It's also something I haven't seen happen before. I think it may have happened to me. Recently I had a missing score error when I was looking for something in my dump fs. To assess the damage I did a 'venti/copy -r' to a spare server, which told me 13 pointers had to be rewritten. I do sometimes get errors like this from my fossil server: could not write super block; waiting 10 seconds blistAlloc: called on clean block but I've been assuming they are benign. Am I wrong? My understanding of fossil is that venti writes are ordered such that the store should not be left in an inconsistent state even after a sudden shutdown. If that's the case, I'm guessing the most likely cause of corruption was a careless experiment with venti when there was already one running.
Re: [9fans] venti
Yes, but even if one venti always leaves the store in a consistent state, running two may still cause them to wite differemt things to the same place on disk and this is likely to result in havoc. Sape ---BeginMessage--- Hmm. Running two ventis on the same data is, of course, bad. It's also something I haven't seen happen before. I think it may have happened to me. Recently I had a missing score error when I was looking for something in my dump fs. To assess the damage I did a 'venti/copy -r' to a spare server, which told me 13 pointers had to be rewritten. I do sometimes get errors like this from my fossil server: could not write super block; waiting 10 seconds blistAlloc: called on clean block but I've been assuming they are benign. Am I wrong? My understanding of fossil is that venti writes are ordered such that the store should not be left in an inconsistent state even after a sudden shutdown. If that's the case, I'm guessing the most likely cause of corruption was a careless experiment with venti when there was already one running. ---End Message---
Re: [9fans] Why do we need syspipe() ?
On Fri, Jan 9, 2009 at 2:05 AM, Roman V. Shaposhnik r...@sun.com wrote: Multiplexing. If devices exposed channel interface, and got exported there would be no kernel protecting from clients sending random sequences of 9P messages (on a single host you can't mount a channel and then continue reading/writing 9P messages over it). a year or so back i mentioned a way that this could be done, by having an auth (DMAUTH) file visible in the namespace representing the channel to be mounted. you can turn this file into a new namespace by opening it and handing it to an attach message (as the afid). i've probably still got a working inferno kernel that i modified to allow this, but i didn't take it any further. this mechanism *could* potentially be used to replace the # namespace.
Re: [9fans] venti
I do sometimes get errors like this from my fossil server: could not write super block; waiting 10 seconds blistAlloc: called on clean block but I've been assuming they are benign. Am I wrong? i looked into this. /sys/src/cmd/fossil/cache.c:1210,1217 if(p-index 0){ /* * We don't know how to temporarily undo * b's dependency on bb, so just don't write b yet. */ if(0) fprint(2, blockWrite skipping %d %x %d %d; need to write %d %x %d\n, b-part, b-addr, b-vers, b-l.type, p-part, p-addr, bb-vers); return 0; } what if bb == b? it'd be interesting to see what that outputs with if(1). i think _cacheLocalLookup is finding the superblock itself. perhaps no write between snaps meaning that only the sb itself is dirty? - erik
[9fans] pull doesn't work due to unavailable sources; travelmate 291LCi specials
Hello, I tried to install plan9 on one of my computers and wanted to update it running 'pull'. However, it doesn't work, perhaps because the home pages of plan9 at Bell labs don't work. I somehow have a feeling there are problems with those pages every now and then. Is it so? Why? May some mirror be used instead? If yes, what and how do I have to modify so that 'pull' then works? Also. My computer is Acer Travelmate 291LCi. It has a touchpad (2 buttons) and I want to use a usb mouse. After installation the touchpad works, but connected external mouse does not. Why? What do I have to do? There is a message saying something like '/dev/usb0/1/ep0data does not exists'. Last, the computer has a 1400x1050 screen, which is somehow not listed in its Bios table, so that I had to run some program to help it under linux (something like 855patch ; http://www.chzsoft.com.ar/855patch.html ; it has a 810i graphics on board). Is there a chance it would work in plan9? What do I have to do? Thanks Ruda
Re: [9fans] pull doesn't work due to unavailable sources; travelmate 291LCi specials
http://www.chzsoft.com.ar/855patch.html ; it has a 810i graphics on board). Is there a chance it would work in plan9? What do I have to do? there was a guy around here who worked up that bios patch for plan 9. (translated, oddly enough, from the original oberon.) i'll try to hunt it down. i can't currently locate it. but if it can't be found, the linux version should be easy enough to translate. - erik
Re: [9fans] pull doesn't work due to unavailable sources; travelmate 291LCi specials
On Fri, Jan 9, 2009 at 11:17 PM, Rudolf Sykora rudolf.syk...@gmail.com wrote: I tried to install plan9 on one of my computers and wanted to update it running 'pull'. However, it doesn't work, perhaps because the home pages of plan9 at Bell labs don't work. I somehow have a feeling there are problems with those pages every now and then. Is it so? Why? Yeah, I can't connect to sources at the moment. I get as far as post... and then 9fs blocks. -sqweek
Re: [9fans] pull doesn't work due to unavailable sources; travelmate 291LCi specials
Hello As soon as the new mirror method mentioned by Geoff becomes the official way to sync mirrors i will update the 9grid.es mirror and i will provide the scripts to pull from 9grid.es again Gabi El 09/01/2009, a las 15:17, Rudolf Sykora rudolf.syk...@gmail.com escribió: Hello, I tried to install plan9 on one of my computers and wanted to update it running 'pull'. However, it doesn't work, perhaps because the home pages of plan9 at Bell labs don't work. I somehow have a feeling there are problems with those pages every now and then. Is it so? Why? May some mirror be used instead? If yes, what and how do I have to modify so that 'pull' then works? Also. My computer is Acer Travelmate 291LCi. It has a touchpad (2 buttons) and I want to use a usb mouse. After installation the touchpad works, but connected external mouse does not. Why? What do I have to do? There is a message saying something like '/dev/usb0/1/ep0data does not exists'. Last, the computer has a 1400x1050 screen, which is somehow not listed in its Bios table, so that I had to run some program to help it under linux (something like 855patch ; http://www.chzsoft.com.ar/855patch.html ; it has a 810i graphics on board). Is there a chance it would work in plan9? What do I have to do? Thanks Ruda
Re: [9fans] pull doesn't work due to unavailable sources; travelmate 291LCi specials
Sorry, which new mirror method? I probably missed that. We keep a mirror of sources/plan9 and 9grid at sources.lsub.org. On Fri, Jan 9, 2009 at 5:37 PM, Gabriel Diaz Lopez de la Llave gd...@9grid.es wrote: Hello As soon as the new mirror method mentioned by Geoff becomes the official way to sync mirrors i will update the 9grid.es mirror and i will provide the scripts to pull from 9grid.es again Gabi El 09/01/2009, a las 15:17, Rudolf Sykora rudolf.syk...@gmail.com escribió: Hello, I tried to install plan9 on one of my computers and wanted to update it running 'pull'. However, it doesn't work, perhaps because the home pages of plan9 at Bell labs don't work. I somehow have a feeling there are problems with those pages every now and then. Is it so? Why? May some mirror be used instead? If yes, what and how do I have to modify so that 'pull' then works? Also. My computer is Acer Travelmate 291LCi. It has a touchpad (2 buttons) and I want to use a usb mouse. After installation the touchpad works, but connected external mouse does not. Why? What do I have to do? There is a message saying something like '/dev/usb0/1/ep0data does not exists'. Last, the computer has a 1400x1050 screen, which is somehow not listed in its Bios table, so that I had to run some program to help it under linux (something like 855patch ; http://www.chzsoft.com.ar/855patch.html ; it has a 810i graphics on board). Is there a chance it would work in plan9? What do I have to do? Thanks Ruda
Re: [9fans] pull doesn't work due to unavailable sources; travelmate 291LCi specials
hello Geoff is working to get a replica/pull set up to mirror /n/sources. 9grid.es stopped mirrorning since this started, and i'm trying from time to time to use the replica/pull system to mirror sources. sorry but i can't remember the message on which Geoff talked about this. gabi El 09/01/2009, a las 17:51, Francisco J Ballesteros escribió: Sorry, which new mirror method? I probably missed that. We keep a mirror of sources/plan9 and 9grid at sources.lsub.org. On Fri, Jan 9, 2009 at 5:37 PM, Gabriel Diaz Lopez de la Llave gd...@9grid.es wrote: Hello As soon as the new mirror method mentioned by Geoff becomes the official way to sync mirrors i will update the 9grid.es mirror and i will provide the scripts to pull from 9grid.es again Gabi El 09/01/2009, a las 15:17, Rudolf Sykora rudolf.syk...@gmail.com escribió: Hello, I tried to install plan9 on one of my computers and wanted to update it running 'pull'. However, it doesn't work, perhaps because the home pages of plan9 at Bell labs don't work. I somehow have a feeling there are problems with those pages every now and then. Is it so? Why? May some mirror be used instead? If yes, what and how do I have to modify so that 'pull' then works? Also. My computer is Acer Travelmate 291LCi. It has a touchpad (2 buttons) and I want to use a usb mouse. After installation the touchpad works, but connected external mouse does not. Why? What do I have to do? There is a message saying something like '/dev/usb0/1/ep0data does not exists'. Last, the computer has a 1400x1050 screen, which is somehow not listed in its Bios table, so that I had to run some program to help it under linux (something like 855patch ; http://www.chzsoft.com.ar/855patch.html ; it has a 810i graphics on board). Is there a chance it would work in plan9? What do I have to do? Thanks Ruda
Re: [9fans] venti
A check could be put in by having venti put some sort of lock somewhere on the disk. But that would lead to problems if venti doesn't shut down properly: venti would be gone but the lock would still be there. Post an (ignored) mode 000 fd in /srv? Since nobody could open it, it would always have one reference, and would go away when the venti did? Dave Eckhardt
Re: [9fans] venti
A check could be put in by having venti put some sort of lock somewhere on the disk. But that would lead to problems if venti doesn't shut down properly: venti would be gone but the lock would still be there. Post an (ignored) mode 000 fd in /srv? Since nobody could open it, it would always have one reference, and would go away when the venti did? dns tries a similar trick. unfortunately, this means that dns doesn't like to be restarted when it's gone haywire as slay dns|rc doesn't seem to remove dns' entry from srv. it also assumes direct-attach storage. - erik
Re: [9fans] venti
Post an (ignored) mode 000 fd in /srv? Since nobody could open it, it would always have one reference, and would go away when the venti did? Kudos to Mr Eckhardt for a very neat solution. -Steve
Re: [9fans] pull doesn't work due to unavailable sources; travelmate 291LCi specials
What was wrong with the old way of doing mirroring with lsr? It worked quite nicely, and was way more reliable and infinitely faster than replica. uriel On Fri, Jan 9, 2009 at 6:36 PM, Gabriel Diaz Lopez de la Llave gd...@9grid.es wrote: hello Geoff is working to get a replica/pull set up to mirror /n/sources. 9grid.es stopped mirrorning since this started, and i'm trying from time to time to use the replica/pull system to mirror sources. sorry but i can't remember the message on which Geoff talked about this. gabi El 09/01/2009, a las 17:51, Francisco J Ballesteros escribió: Sorry, which new mirror method? I probably missed that. We keep a mirror of sources/plan9 and 9grid at sources.lsub.org. On Fri, Jan 9, 2009 at 5:37 PM, Gabriel Diaz Lopez de la Llave gd...@9grid.es wrote: Hello As soon as the new mirror method mentioned by Geoff becomes the official way to sync mirrors i will update the 9grid.es mirror and i will provide the scripts to pull from 9grid.es again Gabi El 09/01/2009, a las 15:17, Rudolf Sykora rudolf.syk...@gmail.com escribió: Hello, I tried to install plan9 on one of my computers and wanted to update it running 'pull'. However, it doesn't work, perhaps because the home pages of plan9 at Bell labs don't work. I somehow have a feeling there are problems with those pages every now and then. Is it so? Why? May some mirror be used instead? If yes, what and how do I have to modify so that 'pull' then works? Also. My computer is Acer Travelmate 291LCi. It has a touchpad (2 buttons) and I want to use a usb mouse. After installation the touchpad works, but connected external mouse does not. Why? What do I have to do? There is a message saying something like '/dev/usb0/1/ep0data does not exists'. Last, the computer has a 1400x1050 screen, which is somehow not listed in its Bios table, so that I had to run some program to help it under linux (something like 855patch ; http://www.chzsoft.com.ar/855patch.html ; it has a 810i graphics on board). Is there a chance it would work in plan9? What do I have to do? Thanks Ruda
Re: [9fans] pull doesn't work due to unavailable sources; travelmate 291LCi specials
it's not reliable. I had to fix several things, but the main problem is that it's not coherent wrt sources. You might end up with incosistent files, depending on when lsr runs. I'm using a variant of lsr, but I'm looking forward to a more coherent way of doing it. On Fri, Jan 9, 2009 at 9:42 PM, Uriel urie...@gmail.com wrote: What was wrong with the old way of doing mirroring with lsr? It worked quite nicely, and was way more reliable and infinitely faster than replica. uriel On Fri, Jan 9, 2009 at 6:36 PM, Gabriel Diaz Lopez de la Llave gd...@9grid.es wrote: hello Geoff is working to get a replica/pull set up to mirror /n/sources. 9grid.es stopped mirrorning since this started, and i'm trying from time to time to use the replica/pull system to mirror sources. sorry but i can't remember the message on which Geoff talked about this. gabi El 09/01/2009, a las 17:51, Francisco J Ballesteros escribió: Sorry, which new mirror method? I probably missed that. We keep a mirror of sources/plan9 and 9grid at sources.lsub.org. On Fri, Jan 9, 2009 at 5:37 PM, Gabriel Diaz Lopez de la Llave gd...@9grid.es wrote: Hello As soon as the new mirror method mentioned by Geoff becomes the official way to sync mirrors i will update the 9grid.es mirror and i will provide the scripts to pull from 9grid.es again Gabi El 09/01/2009, a las 15:17, Rudolf Sykora rudolf.syk...@gmail.com escribió: Hello, I tried to install plan9 on one of my computers and wanted to update it running 'pull'. However, it doesn't work, perhaps because the home pages of plan9 at Bell labs don't work. I somehow have a feeling there are problems with those pages every now and then. Is it so? Why? May some mirror be used instead? If yes, what and how do I have to modify so that 'pull' then works? Also. My computer is Acer Travelmate 291LCi. It has a touchpad (2 buttons) and I want to use a usb mouse. After installation the touchpad works, but connected external mouse does not. Why? What do I have to do? There is a message saying something like '/dev/usb0/1/ep0data does not exists'. Last, the computer has a 1400x1050 screen, which is somehow not listed in its Bios table, so that I had to run some program to help it under linux (something like 855patch ; http://www.chzsoft.com.ar/855patch.html ; it has a 810i graphics on board). Is there a chance it would work in plan9? What do I have to do? Thanks Ruda
Re: [9fans] venti
On Fri, 2009-01-09 at 15:11 -0500, Dave Eckhardt wrote: A check could be put in by having venti put some sort of lock somewhere on the disk. But that would lead to problems if venti doesn't shut down properly: venti would be gone but the lock would still be there. Post an (ignored) mode 000 fd in /srv? Since nobody could open it, it would always have one reference, and would go away when the venti did? Very neat! One question though: since a hostowner can change permissions on the entry later, this still doesn't offer a guarantee of a single reference, does it? Thanks, Roman.
Re: [9fans] cheap, low-resolution terminal
What'd you say if you had my keyboard? It's got a couple of (useful) Windows keys, a numeric pad, and some multimedia keys. Can't complain, to each their lot ;-) And for the oldies fun: last week I had to replace an AT type PSU and get the right wires (white, black, brown, blue) connected to the right pins or the replacement would go where the fried one went. Don't ask how I found the replacement in the first place. --On Thursday, January 08, 2009 2:20 PM -0500 j...@csplan9.rit.edu wrote: [...] Last thing I did before I packed it in was take the superimposed picture and look at it through a green filter. You remember I was always superstitious about the color green when I was a kid? I always wanted to be a pilot on one of the trading scouts? I love green and I admire your taste, John Floren. Thank you By the way, this was the first picture of a VT220 I had ever seen in my life. The no-frills keyboard looks even cooler than the display. The keyboard is nice to type on, but unfortunately it's a VMS layout; there is also a UNIX layout but I don't have that. The result is that I have a really long keyboard (it has a numberpad/EDIT keypad off-screen to the right) instead of a short keypad-less UNIX board, and the Control key is on the wrong side of the caps lock key. Still, a fun piece of equipment. John --On Wednesday, January 07, 2009 10:10 PM -0500 j...@csplan9.rit.edu wrote: http://csplan9.rit.edu/users/john/plan9vt220-full.jpeg http://csplan9.rit.edu/users/john/plan9vt220-screen.jpeg Just threw this onto my CPU server (yes, mock my slow processor, it was free) and was once again pleased with how easy it is to set stuff up on Plan 9. Just one line in plan9.ini and I was rocking. John Floren
Re: [9fans] venti
Post an (ignored) mode 000 fd in /srv? Since nobody could open it, it would always have one reference, and would go away when the venti did? dns tries a similar trick. I think /srv/dns serves an actual file system, so there are potentially many references to it (not just one). it also assumes direct-attach storage. Not exactly, but you are right that ventis running on two kernels could mount the same storage. I seem to recall being surprised at some point to observe /dev/sdXX/data silently imposing a one-open-at-a-time policy (I think subsequent opens stalled). Maybe a script run at system boot time could turn on DMEXCL for appropriate things in /dev/sd*/*? Dave Eckhardt
Re: [9fans] pull doesn't work due to unavailable sources; travelmate 291LCi specials
On Fri, Jan 09, 2009 at 09:54:02PM +0100, Francisco J Ballesteros wrote: it's not reliable. I had to fix several things, but the main problem is that it's not coherent wrt sources. You might end up with incosistent files, depending on when lsr runs. I'm using a variant of lsr, but I'm looking forward to a more coherent way of doing it. I am still missing something (and did not get a response on an earlier attempt at asking a slightly different question), but... why doesn't sources 1) allow read-only access to its backing venti to the Internet at large 2) nightly run a full vac job against the nightly dump [1] as none [2] and 3) publish the score so derived? [3] This makes venti/copy -f an excellent mirroring mechanism; mirrors would be only very slightly lagged from the official sources (see [1]), and it would seem to have only very modest bandwidth requirements relative to full tree traversal. If this an acceptable mechanism (I don't see anything wrong with it, but I've been wrong before), I'd be very happy if somebody seeded the system with the dumps already taken. [1] And/or snapshots. Those would work just as well, be just as coherent, and be more frequent in case nightly crawls aren't good enough. [2] Running as none means that only world-readable files get included in the published capabilities. Presumably that's exactly the class that would be mirrored. [3] A vac archive generated by merging each run's vac output, say, with the last run's root score published at the root of sources? Thanks much. --nwf; pgpnibPr4kN13.pgp Description: PGP signature
Re: [9fans] venti
I seem to recall being surprised at some point to observe /dev/sdXX/data silently imposing a one-open-at-a-time policy (I think subsequent opens stalled). Maybe a script run at system boot time could turn on DMEXCL for appropriate things in /dev/sd*/*? i think you mean the raw file. ; cat fu.c #include u.h #include libc.h void main(void) { int i, fd[2]; for(i = 0; i nelem(fd); i++){ fd[i] = open(/dev/sdC0/data, OREAD); print(fd = %d\n, fd[i]); } exits(); } ; 8c fu.c 8l fu.8 8.out 3 4 - erik
[9fans] serial consoles vs. new motherboards
it's becoming increasingly popular for manufacturers to ship motherboards with no serial ports at all. my terminal has nonfunctional uarts. it's easy enough to add in pci(e) based serial cards. i just got a startech pex2s with 2x 16c950 uarts. unfortunately, i didn't realize that only i8250 work as consoles. this makes sense if you always get a serial console, since pci uarts are obviously not available until the pci bus has been scanned, which is much later in the boot process than the onboard uarts can be enabled. but, i don't have much choice. initially i copied the code from uarti8250.c and got things going, but that doesn't help anyone with a uartixp or an uartisa part, and it seemed like a hokey way of doing things. so on a flier, i rearranged things a little bit by doing two odd things, - adding a function uartconsconf that returns the uart number and the boot-time cmd string. - adding a command for enabling a console on a uart (z). thus, uartreset just needs to call uartsconsconf to find the boot-time console and call uartctl twice to configure any console. for special consoles that can be enabled really early in boot, a very simple function is needed. i8250console, for example, becomes: void i8250console(void) { int n; char *cmd; n = uartconsconf(cmd); if(n == 0 || n == 1){ uartctl(i8250uart + n, z); uartctl(i8250uart + n, cmd); } } (i think a similar trick would work for other arches' consoles.) as a bonus, adding a command (y) to disable a uart console fell out naturally. this is could have saved a few reboots had it been available before! in any event, i welcome any feedback. - erik
[9fans] a bug in awk?
hi, while i was playing with venti archive, i found something interesting. i used dumpvacroots.new (from contrib) and for some reason, awk bailed out with floating point error whenever it saw a line with a specific root score. here are the two sample lines (i used customized printarena.c which prints the date for me at the end): 11260359 d05544897ff642ca36e58174bc753b0f3382b793 0 8192 Jan 9 18:09 11258672 5946903e318d3596c21e35b42a13c1dea5fd32cc 0 8192 Jan 9 18:09 awk seems to be okay with the first line but not the second line. here is the output when i use awk: mill# awk ' { print $0; print NF}' /tmp/out1.dat 11260359 d05544897ff642ca36e58174bc753b0f3382b793 0 8192 Jan 9 18:09 7 11258672 5946903e318d3596c21e35b42a13c1dea5fd32cc 0 8192 Jan 9 18:09 awk: floating point exception 6 input record /tmp/out1.dat:2 source line 1 i figured that: - awk runs fine if i dont print NF. (so, it parses the line on-demand and parsing fails?) - awk doesnt seem to like the score 594632cc. If I change that score to something else and rerun, it seems to be fine. to confirm that this is a plan9 specific awk issue, i tried the same with my Mac machine. it seems to be okay: $ awk ' { print $0; print NF }' out1.dat 11260359 d05544897ff642ca36e58174bc753b0f3382b793 0 8192 Jan 9 18:09 7 11258672 5946903e318d3596c21e35b42a13c1dea5fd32cc 0 8192 Jan 9 18:09 7 what could be the issue? any clues? i initially thought my venti data got corrupted but i am now convinced that this is something else, since i was also able to reliably archive data. thanks dharani
Re: [9fans] a bug in awk?
11258672 5946903e318d3596c21e35b42a13c1dea5fd32cc 0 Note the 5946903e318 which AWK may mistakenly treat as a floating point constant. Now to figure how to prevent such errors... ++L
Re: [9fans] a bug in awk?
hi lucio, so, it tries to interpret as a floating-point no and goes for a toss! thanks for the quick response. regards dharani On Fri, Jan 9, 2009 at 10:26 PM, lu...@proxima.alt.za wrote: 11258672 5946903e318d3596c21e35b42a13c1dea5fd32cc 0 Note the 5946903e318 which AWK may mistakenly treat as a floating point constant. Now to figure how to prevent such errors... ++L