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November 2004

How old is that file? 
- Finding out how old a file is in minutes (or even seconds) is easy enough with Perl 'stat'.
 
shar: Tech Words of the Day 
- If you have ever read Kernigan and Pike's classic Unix Programming Environment Handbook, you may remember the "bundle" script presented there. "shar" is a grown-up, steroid enhanced version of that.
 
Notes on Digiboard Terminal Servers TS/8 TS/16 
- Replacing serial boxes using Frame Relay with Digiboard Port Servers over a VPN.
 
Values Versus Goals  by John G. Spragge
- If you work in computers and you value a sharing community of equals, or you simply want the freedom to produce as good a product as you can, your goals may well include the success of Linux and the free software or open source movements. If, on the other hand, you believe the universe or the Creator have singled some of us out for favour and success, and the rest of us ought to serve and elevate those people, then the free software and open source movements may offend you. Beliefs and values such as these offer a complete vision of the world, one not subject to any empirical test. Within broad limits, we each hold certain values and believe certain things.
 
Popper Fix for SCO 5.0.7  by Tom
- When we installed OpenServer 5.0.7, we found that there was a problem with the popper. It was leaving files in the /tmp directory after each person had popped their email. That alone was just an annoyance and it has been reported on the web already. The real problem was that when the user tried to pop their email again later, some of them were getting the message that their email was "being read by another session." When we removed the temporary file associated with the user that was having problems, the problem went away. I suspect that it is because the PID in the temporary file was being reused, but don't have proof of that.
 
AIDE: Tech Words of the Day 
- A free replacement for tripwire. According to the source page - http://sourceforge.net/projects/aide - this caught a break in at debian.org.
 
Open Source ERP, CRM Software   by Drag Sidious
- Compiere is a interesting piece of software I found while reading a interview of Jon "Maddog" Hall about the current state of Linux acceptance in the enterprise market. The interviewer mentioned Compiere in a question on OSS "software stacks", so I decided to look it up.
 
Formmail: Tech Words of the Day 
- Probably 'Matt's Formmail' though there are other scripts out there with the same name and purpose. Most webmasters will tell you that their http logs are filled with records indicating attempts to execute /cgi-bin/FormMail.pl
 
Another RAID failure 
- Sometimes the worst part of a raid failure can be working with people. The hardware and software usually makes sense; people may not.
 
IS THIS THE END?  by BigDumbDinosaur
- I'm against SCO's attempt to shore up the bottom line via their 'Linux stole our code' lawsuits.
 
rot13: Tech Words of the Day 
- The most advanced encryption available today. OK, just kidding, but Julius Caesar's day, this was hot stuff. Nowadays, it's so well known that it's used just for things like protecting a jokes punchline, or hiding potentially offensive text until the reade decides they want to see it.
 
unison: Tech Words of the Day 
- Unison is similar to rsync, and has a Windows version. There are binaries and ports available, but if you need or want to build this, you need an Objective Caml compiler
 
Waiting too long to upgrade 
- I had related at "Another Raid Failure" that an initial attempt to rebuild the raid had failed, and left the story with fresh drives on order and winging their way toward us. The drives did arrive, but unfortunately the rebuild still failed. A Knowledge Base article suggested that there might be unreported problems on other elements of the array, with the suggested solution of blowing it all away and recreating from scratch. As we still had some suspicions about backups at that point, I didn't want to do that until we had unquestioned good recovery capability.
 
Anonymous donation 
- We get donations now and then, but usually not anonymous. I like to send off a little thank you note by email or postal for any donation, no matter how small. From time to time I've had a dollar or two stuffed in an unmarked envelope with no identification and even those bother me just a little - I'd like to say "Thanks!".
 
regex: Tech Words of the Day 
- Regular Expression. The type of pattern matching you do with sed or grep or Perl uses regexes. There are whole books on regular expressions. I imagine most of us have some degree of familiarity, but this can be a very complex subject.
 
Linux|Unix Trace Toolkit: Tech Words of the Day 
- Sometimes you want to trace a specific process, and strace does that nicely. But other times you may need to see more about the whole system as it reacts with your program. That's what LTT is for
 
LyX: Tech Words of the Day 
- Lyx outputs LaTex. A GUI word processor that outputs LaTex files. Why would you want to do this? Probably if you had to share documents with someone who uses TEX but don't want the trouble of learning it.
 
Twenty Year support contracts 
- Some vendors try to lock you in. Then there are some who REALLY want to lock you in!
 
PAM: Tech Words of the Day 
- Pluggable Authentication Module. I think this is one of the all time best ideas ever. I do think it could use some polishing on the configuration side: it should be easier and less confusing, but the basic idea of flexible authentication is beautiful.
 
Yellow Dog Linux: Tech Words of the Day 
- Linux for Macs. I thought this was near dead, but apparently not: http://www.yellowdoglinux.com/ announced version 4.0 (based on Fedora Core 2) in September 2004.
 
Inetd environment variables 
- Someone asked me recently where inetd gets its environment from. I said I didn't know for sure, but (since there's no place I know of to set them anywhere) I would expect it would inherit from whatever starts it. The person asking was running a SCO system, so that would be /etc/tcp. Most Linuxes now run xinetd, which lets you specify "env" in its xinetd.conf, but even those values are just added to (or replace) whatever it picks up from its startup heritage.
 
blosxom Blogging tool : Tech Words of the Day 
- A simple Perl blogging tool. It doesn't require MySQL or really anything beyond the most basic Perl, so it is easy to plug in anywhere. It uses text files as its database, thus making it easy to interface with anything else.
 
Mac OS X Power Hound 
- 0ob Griffiths is the creator of Macosxhints.com and you could describe this book as a loosely organized version of the better hints and tips you'll find there.
 
Hubris to Go  by BigDumbDinosaur
- Steve Ballmer, Microsoft's highly paid shill, goes on to say, in effect, that non-USA users of Linux and other such OSS could be sued by US parties laying claim to intellectual property rights that Linux developers have supposedly misappropriated.
 
unionfs: Tech Words of the Day 
- So what's a union mount? Imagine you have a directory with files in it, and you then mount some device on that directory. Ordinarily, the original files would no longer be available, but a union mount leaves them visible: you can see both the files from the device you mounted and the files that were originally in the directory you mounted it on.
 
The cable guy (book donations) 
- Old computer programming books are always going to be useful to someone. I was happy to be able to help this young man with C/C++ books.
 
Catb: Tech Words of the Day 
- Eric S. Raymond's 'The Cathedral & the Bazaar'. I couldn't find my copy - thought I had lent it to someone - and I wanted to read it again. Bummer. Happily, I spotted it mis-shelved just this morning. Read it again, and still don't understand why anyone but a fellow geek would enjoy this. And yet the popular press praised it.
 
Microsoft proprietary information in SCO  by Bruce Garlock
- What on earth could Microsoft have that is proprietary with tuning the SCO kernel?
 
Is Microsoft getting used to hearing about Linux? 
- Blog # 1143 Is Microsoft getting used to hearing aboutLinux?
 
Inexpensive GPS units 
- Inexpensive GPS units are an endangered species. GPS software in smart phones is taking over in spite of small screen sizes.
 
Kino: Tech Words of the Day 
- I don't even own a camcorder and can't imagine that I ever will, but if I did, I'd probably use a Mac for video editing.
 
Dead Rat fixes computer problem 
- This is a story of how a dead rat solved a problem. Well, maybe. Actually, at this writing I still don't know what the problem is, but, thanks to a dead rat or two, I do know what the problem isn't.
 
Grass: Tech Words of the Day 
- GRASS GIS (Geographic Resources Analysis Support System) http://grass.fbk.eu/. Map rendering, etc. Linux and many other platforms. Mac OSX port at http://openosx.com/grass/index.html
 
apmd: Tech Words of the Day 
- Tip for laptop users: do you think you can just run out to Walmart and buy an extra battery and/or charger cable?
 
ZFS: Tech Words of the Day 
- ZFS is supposed to be easier to comprehend and administer. I'm all for that: I have often complained that filesystems like Veritas (a former favorite of Sun) can be very difficult. I have yet to put up a Solaris 10 box so am not ready to agree that it is easy yet, but any improvement will be welcome.
 
copyleft: Tech Words of the Day 
- A generic term for open source licensing. Used to be common for websites; is not now.
 
Sun offering free, open source Solaris 10 - not quite yet 
- Sun offering free, open source Solaris 10 - notquite yet
 
N1 Grid Containers: Tech Words of the Day 
- This is Sun's awful name for their server virtualization capability in Solaris 10. This lets you set up up to 4,000 virtual Solaris machines which use a common kernel (thus meaning one point for kernel patches,etc) but having their own IP address, memory, file area, host name, and root password.
 
Sun and open source 
- Can you make money with open source? I think yes, but that doesn't mean many will try it. Had Unix vendors understood what their greed and shor
 
Active Directory: Tech Words of the Day 
- Microsoft's replacement for the awful Domain Controller concept. Two important things you need to understand here are that it is really LDAP, and that it is (or can be) distributed.
 
SCO Web site defaced 
- Amusingly, in March 2011, SCO is running their site on.. wait for it... SCO Unix!
 
Estimating for Consultants 
- I won't do estimates for even the most trivial work. If I can, I'll give you a rough idea of what kind of time might be required, but there is no way that I'm going to quote a not-to-exceed price for anything. Well, that's not entirely true: once in a great while, if I have one of those strange situations where the received value is much higher than the work involved, or where it's something I want to do for educational purposes, I may give a firm price. I might also do it for a charity where I'm intending to charge them as little as I possibly can anyway. But generally, no way - I sell time and knowledge, not necessarily results.
 
latency: Tech Words of the Day 
- Basically, delay. Different from bandwidth, and the source of unending confusion and argument because of that. Latency affects everything from hard drives to the internet.
 
Determining clients IP address by service and PID  by BigDumbDinosaur
- I wrote this thing several years ago for use with a program where I needed to know a client's IP address, given the TCP service on which they were connected and the program's PID
 
Terminal server, Remote Desktop, thin clients and all that 
- No wonder people get confused. Lots of similar or related things, no end of licensing confusion, no end of general confusion.