warcow105 - Slashdot User

Submission + - Happy birthday Nmap

Submitted by mrwolf007 on Friday December 14, 2007 @07:23PM

mrwolf007 writes: For those of you who havent heard it yet, Nmap is now ten years old. The network scanner is now available in version 4.5, which is the first mayor release since 4.0 two years ago. Looking past, Nmap has been featured in at least 5 films, inclunding the second part of Matrix and The Bourne Ultimatum, and is probably in the toolbox of almost every person interested in network security, be it jobwise or otherwise. Further information can be found on the official release notes.

Submission + - Evel Knievel Dies at 69 (blogspot.com)

Submitted by jazmynmarie on Friday November 30, 2007 @11:31PM

jazmynmarie writes: Evel Knievel died Friday after 69 years, which is more than twice as long as it by all rights should have taken him. Knievel, who had been in poor health...

Submission + - Shell Script Pearls

Submitted by

bdgrell

on Tuesday November 27, 2007 @02:04AM

bdgrell writes: "Everyone who has used a UNIX based system for any length of time has come to rely on shell scripts. Shell scripting is a universal language on UNIX systems, usually the first any administrator learns and uses in their own environment. Whether its a small one-liner to perform a small task, or a large complex script that is critical to the environment, each user has their own bag of tricks for accomplishing everyday tasks. Shell Script Pearls is a collection of various shell scripting techniques that the author Ron Peters has found during his years as a system administrator.

With perhaps a nod to one of the many other languages available for scripting, Shell Script Pearls is a handy reference book to have when trying to filter strings in log files or remember how to perform exponentiation math from the command line. While there aren't as many complete scripting examples as you might find in a regular recipes or cookbook, there are a lot of examples for how to perform a certain task. Spanning 42 chapters, the book is mostly divided into 4 categories: general scripting utilities, handling user input, text processing, and system administration. As the author states in the introduction, the book is mostly targeted at intermediate or advanced Unix/Linux users, as it assumes a certain level of proficiency with commands and how to use them.

While sometimes techniques within a chapter will build upon one another, the chapters themselves usually don't have any relation to each other. This makes the book less readable from cover to cover, and is best used more like a reference book. Each chapter is focused on accomplishing a technique, usually presented as a real world problem to solve, which the author has encountered in his own career. The background information supplied for some of the more unique challenges helps to understand why certain methods were used as opposed to others. The personal stories also affirm that the author has actually used all of these techniques at one point, and they aren't just solutions to hypothetical problems.

The usefulness of some of the techniques will vary depending on the situation and the skill set of the reader. Often times the author will present how to perform a task in multiple ways, such as calculating the length of a string using either awk or expr. Some examples are even shown using multiple shells, since the syntax and functions may differ. The appendix also has a great list of other shell scripting resources, so if you don't find what you need in this book you have a few other places to look as well.

One thing that is immediately noticeable is the author chose to differ in presentation of the scripts from other technical books. Instead of having all of the code in one continuous chunk, he will often present a small snippet and then explain what that section of code is doing. Then he will present another section of code with the corresponding explanation of the technique that he is trying to illustrate. It is rare to find more than 9 or 10 lines of code without a comment which I found made it much easier to follow what the scripts was doing.

Overall, there aren't as many scripts that you might find in a scripting cookbook. Also, the chapter about the X envronment really seemed out of place, explaining various environment settings rather than providing examples of scripting. The scripts in the book are high quality, but have been stripped down for illustrative purposes, so you won't find a lot of error checking. I wasn't able to find any place on the authors website to download any of the scripts either, so the only option is to copy what you need out of the book.

Aside from those minor issues, Shell Script Pearls is an excellent book to have at close reach when writing shell scripts. Even in the age of large search engines, sometimes it's easier to just use a sticky note to remember a command to get the job done easier."

Submission + - Worlds First Sega CD Emulator for PSP Released

Submitted by Croakyvoice on Sunday November 18, 2007 @01:10AM

Croakyvoice writes: Notaz has today released the worlds first Sega CD Emulator for the PSP, the emulator runs many Genesis and Sega CD games at Full Speed, " There seemed to be some demand for Sega CD/Mega CD emulator for PSP, so after doing the Gizmondo port I decided to port PicoDrive, my Genesis/MegaDrive/Sega CD/Mega CD emulator, to PSP. There is nothing fancy about this emulator (no dynarecs/asm cores), but it's still able to run many Genesis games fullspeed with no frameskip (including some CD ones), and others with some skipping."

Submission + - New helmet allows pilots to see through aircraft (scifi.com)

Submitted by

Lucas123

on Friday November 16, 2007 @01:36PM

Lucas123 writes: "A helmet being built by Vision Systems International and Helmet Integrated Systems, and being tested by the Royal Air Force's Centre for Aviation Medicine, will allow pilots of the F-35 Joint Strike Fighter to see through the aircraft around them for a better field of vision. The image pilots receive is a superimposed Infrared one of the world below projected onto their visors at night. "The helmet also operates in tandem with the system of "symbology" the aircraft uses rather than a traditional heads-up display, allowing information about the plane — navigation, weapon systems, system status, etc — to be projected directly onto the pilot's helmet. The F-35 JSF is the first fighter jet in 50 years not to use a HUD.""

Submission + - Optic flow guides us in the right direction

Submitted by

Roland Piquepaille

on Friday November 16, 2007 @01:35PM

Roland Piquepaille writes: "The way we perceive the visual motion of objects as we move is a phenomenon called 'optic flow.' Now, Brown University researchers have discovered that optic flow helps us to walk. They've used Brown's Virtual Environment Navigation Lab, or VENLab, one of the largest virtual reality labs in the U.S. to conduct trials on 40 subjects. All of them had to find a virtual doorway, but half of the subjects had optic flow, or a stream of visual information, available to them, while the other half had not. The results were spectacular. With optic flow, the subjects adapted themselves 7 times faster to their virtual environment than the other ones. This discovery could soon be applied in robotics to develop machines with more accurate guidance capabilities. But read more for additional details and a picture showing how difficult it is to find a virtual door without guidance from optic flow."

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