Paw Prints: Writings of the maddog

Jon
dd(1): deceptively simple

Oct 26, 2010 GMT

 Unix (and Linux) command line programs are like old friends. You get caught up in the day-to-day hustle of life and you may forget about them temporarily, but sooner or later you remember them and that warm feeling comes over you.... dd(1) is one of those programs that gives me a warm feeling. How simple dd(1) seems to most people, just reading in data at one end of the program and outputting the data at the other end, perhaps doing a little data blocking or unblocking and perhaps a little conversion. And of course a lot of us use dd(1) to clone disk drives and other “utility” tasks, because dd(1) is simple, fast and can work from a command line. Yet on two separate...
What's In A Name? The story of DLT vs dlt

Oct 25, 2010 GMT

 The TK50 was a cartridge tape and tape drive system launched by Digital Equipment Corporation in 1984. It was not the first cartridge tape that came out. 3M had developed a cartridge tape called “QIC” for “Quarter Inch Cartridge” in 1972, and our Unix systems supported that, but Digital also decided to create its own tape cartridge and drive, and of course it was deemed to be “proprietary”. For its day it was a competitive system: o it used a pocket-size tape cartridge (o.k....for a large, coat-sized pocket) o it used a “serpentine motion” which meant that it would write to the end of the tape, then shift the heads slightly and continue writing as the...
The Needs of the Many

Sep 30, 2010 GMT

 "The Needs of the Many Must Outweigh the Needs of the Few..or the One." - Spock in “Star Trek: The Wrath of Khan” With those words Spock chose to die in order to save the rest of the crew. Philosophically whether you agree to what Spock said or not, an important part of the lesson was that Spock chose to act the way he did...he exercised choice. Sometimes developers inadvertantly do not offer as much choice to their customers as they should. For example, when we choose not to engineer and offer a clean upgrade path to a new version of a program or distribution. Many years ago I helped design a new "update" facility for Digital's Ultrix...
Storage of clear-text passwords: NOT!

Sep 30, 2010 GMT

 I am the first person to admit that I am not an expert on security (o.k., there are probably several dozens of my friends who will gleefully “admit” that I am not an expert on security before I will), but I do know that storing passwords in clear-text is just not the way to go. Yet recent interactions with several web site management teams has shown me that apparently some people have not yet learned this simple principle. With all the reported incidents of identity theft due to records and data stolen you would hope that companies would treat passwords with more respect, yet I have one “social network” site email me information on my account each month where they...
Late Night Frustrations

Sep 29, 2010 GMT

 From time to time I write about Project Cauã, and how it might help the average person by supplying them with a local systems administrator to help them fix problems on their computer system. I use Evolution as my mail/contacts/calendar/task manager. About three days ago my outgoing email stopped working. I could access the incoming email, but all outgoing email simply stayed in the outbox of Evolution. When I tried to schedule the email for delivery, dialog boxes would come up telling me that my smtp server was denying access. Almost simultaneously I saw a brief tweet from my ISP mentioning that they were “working on a problem” (but no real description of the problem), so...
Mocking fortunes

Sep 28, 2010 GMT

X windows: The ultimate bottleneck. Flawed beyond belief. The only thing you have to fear. Somewhere between chaos and insanity. On autopilot to oblivion. The joke that kills. A disgrace you can be proud of. A mistake carried out to perfection. Belongs more to the problem set than the solution set. To err is X windows. Ignorance is our most important resource. Complex nonsolutions to simple nonproblems. Built to fall apart. Nullifying centuries of progress. Falling to new depths of inefficiency. The last thing you need. The defacto substandard. Elevating brain damage to an art form. X windows. Those of you who know me may be surprised to see such venom against the really...
Will Code For Beer

Sep 27, 2010 GMT

 People ask me why programmers write code and give it away “for free”. There are many reasons, but one I often give is that a programmer might end up at a conference and a grateful user of their code might “buy them a beer, or even a dinner.” It was February or March of 1995, and the port of Linux to the Alpha processor was well underway. In talking with some of the developers over the Internet, I started to hear rumors that the Alpha port would not have “shared libraries”, but instead would have statically-linked binaries. For those of you who do not understand the ramifications of statically linked binaries, it means that every program has all of the libraries...
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