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January 2004

The Twinkie - I mean SCO - Defense 
- No, I didn't steal the code - I stole it from somewhere else and then he stole it from me.
More on Patents 
- Patents, when held by uber-rich corporations, can stifle innovation because no small person dare invent anything.
SCO Sympathiser 
- I'm definitely not a SCO supporter. I want them to lose this lawsuit. That doesn't mean I ignore reality.
MYDOOM virus attacks SCO site 
- Childish attacks like this are most definitely NOT COOL. Whoever did this needs to grow up.
PHP and today's generation of web technologies.  by Crouse
- The first generation of design would have to be called the STATIC generation. In the static generation of web design, pages were mostly html pages that relied soley on static text and images.
Weather Forecast Data 
- The National Weather Service publishes a tremendous amount of information at http://www.nws.noaa.gov/. What you may not know is that they also make data available via ftp. There's an experimental project that you might enjoy.
Dreading the Writing Assignment? Outlines to the Rescue  by Christine Taylor
- Outlining keeps you from writing an unstructured mess. Readers, especially American readers, prefer distinct sections in their media. For example, look at American screenplays. Movies invariably have three acts, and anything that doesn't have them is considered an art film. Effective speeches often contain three parts, and readers like three points because the structure makes easier to retain information.
Debugging a failing pop mail connection 
- A user at the remote site of a dedicated T1 connection complained that intermittently he could not send or receive mail.
Why I am changing to emacs  by Mike Hostetler
- I was a vim user for a long time but recently I decided to try emacs a try.
Unixware and the Open Server Kernel Personality  by Roberto Zini
- The OpenServer Kernel Personality (OKP) module is a special layer of software that can be installed over an existing UnixWare 7.1.3. system as to allow existing OpenServer 5.0.x applications to run unmodified under the UnixWare7 environment. This module allows users with existing OS5 apps to migrate to the newer UW7 platform without having to reinstall or configure the software.
- Netinfo is gone as of Leopard (October 2007). Good riddance. Mac OS X, though Unix based, departs from Unix flat files in a number of areas and uses a database instead. In some cases, the system respects the information in the flat files, and in others it doesn't. Confusion reigns.
- An alternative to sendmail. It's really surprising that, given sendmail's troubled security history, so many Unix/Linux sites still use it. One advantage is its ubiquitous nature: it's easy to find sendmail resources and recipes.
- Web page indexing. It's fast, and adaptable: you can script the results to your liking. I had to give up Swishe-e as my site got larger and larger. The index became enormous and took way too long to rebuild.
- Calculators. The dc is RPN, which I never liked. Both of these are arbitrary precision, which means that they can calculate numbers out to the limits of your virtual memory. You can do nice base conversion with bc
- Hunt the Wumpus was an early game often found on Unix systems. You can relive those days of old in various places
- What does 'not a typewriter' mean? What is a block device?'? What is a character device?
- Device files show up in long listings with two numbers where the size would ordinarily be. The first number is the major number for the device, and actually is simply an index into a table of memory addresses in your kernel. When you attempt to open /dev/tty, the kernel calls the code referenced by position one in its index. The second number (the minor number) is passed to that code as an argument.
- (Linux) A more user-friendly 'kill'. A bit more ease of use never hurts. This isn't all that friendly though. For example, while 'skill -iu fred' happily brings up each of fred's processes for you to kill or not, 'skill -i -u fred' just does nothing -
- Compare Grub features to a more primitive SCO boot loader.
- Basic Input/Output System The low level code that gets things rolling. I was interested in reading about 'http://www.linuxbios.org/' The Linux BIOS.. One early problem the developers had was that it got running so quickly that the hard drives weren't yet ready!
- That can be useful for small chunks of data you want to carry with a program, but it's also handy while writing code: stash samples from data files where you can easily review them, or read in code from elsewhere you want to cut and paste from.
- Structured (or Standard) Query Language Most databases nowadays offer an SQL interface, and some offer nothing else. In theory, given the same table names and relationships, an SQL query should produce similar results no matter what database it is actually accessing.
- If referring to a hard disk, this is files having data that isn't in contiguous areas of the drive. While that's not necessarily the best situation, neither is it always something you need to be concerned about.
- Fetchmail handles POP or IMAP servers (and SMTP ETRN). It's simple to configure for multiple accounts, can deliver mail to different mailboxes, etc. Very flexible and powerful.
- Proxy servers are a convenient point to implement web access control (blocking people from going to certain sites)
- Floppy disk, anywhere from the giant 8 inch versions to the nearly extinct 3.5 inch versions most machines still come with even if the drive may never be used. I was surprised today when I overheard my wife, who certainly is far less than a tech maven, telling her sister 'Nobody uses floppies anymore"
- There's a subtle difference between broadcasting and multicasting: every host on a network sees a broadcast packet, but multicast data is only picked up by the machines that WANT it. Typical uses for this are live streaming of audio or visual data.
- These are the methods that device drivers provide for functions that can't be accomplished through normal i/o. For example, a tape driver will have an ioctl call to set compression. See http://aplawrence.com/Unix/lpstatus.html for more examples.
- High capacity, high speed (and higher cost) tape storage. The interesting thing about this technology is that the tape media has an EEPROM in it that stores information about the tape contents, the number of times the tape has been used and other useful info that can be queried without ever moving the tape itself.
- These are very inexpensive tape drives with a horrible reputation for quality. The tapes are expensive, because that's where all the engineering is: the drive itself is basically dumb.
- The idea behind hyperthreading is that different process threads may demand different processor resources. For example, one thread might make extensive use of floating point, while the other threads do not.


- You don't have to hang around Unix long to learn about 'su' and setuid programs. The 'setuid()' system call (and related calls like setgid) are what allows a process to switch back and forth between id's.
- A spurious interrupt is an interrupt the driver didn't expect. Briefly, devices such as disks, parallel ports, serial ports, etc. use interrupts to signal back to the cpu that they have completed the last task given them or that the device has recieved data.
Using Open Source applications for web design  by Crouse
- When I think of Open Source applications, my first thoughts always connect it to Linux. Since it is the most recognized Open Source operating system, for now we will concentrate on using Linux for web design.
Newbie guide for the net install of SuSe 9.0  by Crouse
- Since SuSe doesn't offer free iso download versions of SuSe, I decided to write this guide on how to do an net install (ftp install) of SuSe 9.0 since that is something that they do offer for free, but don't offer support. They do offer a "guide" to installing SuSe from the net, but it lacks detail and seems intentionally cryptic to me.
The Gimp: Making Colors in a GIF Transparent  by Crouse
- Sometimes when working with an image you want to make a certain color transparent. When working with a gif file this would make a round circle look round on any color background. This is actually very simple once you do it once. Finding the information for this took me a while so I thought I would pass it on to anyone that was interested.