Malicious Linux Commands - From (This article was originally published in Ubuntu Forums but was removed there. Ubuntuguide feels that knowledge about these risks is more important than any misguided attempts to "protect the public" by hiding their potential dangers or protect the (K)Ubuntu/Linux image. The original article has therefore been re-created (and subsequently edited) here.) ATTENTION: It is worthwhile to have some basic awareness about malicious commands in Linux. It is also worthwhile to always enable a Kubuntu screensaver or Ubuntu screensaver with a password so that a casual passerby is not able to maliciously execute one of these commands from your keyboard while you are away from your computer. When in doubt as to the safety of a recommended procedure or command, it is best to verify the command's function from several sources, such as from readily available documentation on Linux commands (e.g. manpages). Here are some common examples of dangerous commands that should raise a red flag. rm -r In Perl
50 Open Source Tools to Make Your Life Easier The open source community is vibrant, continually growing, and just loves to create applications and tools to make lives easier. Here are 50 of our favorite open source apps that help us do everything from managing pictures on our computer to learning about Jupiter and Mars. Chandler – An information management application for personal use or small group collaboration. Includes integrated calendaring, data organization tools, and allows backup and data sharing via web access. Tomboy – A cross-platform note-taking application packed with features text highlighting, font styling, inline spellchecking, and more. BasKet Note Pads – More than just a note-taking app, BasKet lets you organize in track data in several different ways, import information from other apps, and easily share your notes with others. Freemind – This free mind mapping app can easily handle maps with as many as 22,000 nodes. Task Coach – A robust todo list tracker. Xchat – An IRC chat client for Linux and WIndow.
How to generate a stacktrace when my gcc C++ app crashes Kinect-like technology turns any surface into a touchscreen Imagine a world where any surface could potentially become a touchscreen for your phone: your hands, clothes, a wall or table. That's the vision behind a new Kinect-like technology called OmniTouch, a wearable system that projects any multi-touch interface onto everyday surfaces, reports New Scientist. Perhaps the most convenient aspect of the technology is how it can be operated on the go, requiring no special calibration for each new surface it is used on. The system adapts easily to surfaces of most textures in 3D space, so it works even when the surface is not flat, such as with your hand, or perhaps a tree trunk. The technology, which is primarily composed of a shoulder-mounted depth camera and a Pico-projector, was developed by researchers at Microsoft and is a vast improvement over previous prototypes that could only work on skin. The device also allows for user flexibility far beyond the capability of your phone or tablet.
JamesM's kernel development tutorials This set of tutorials aims to take you through programming a simple UNIX-clone operating system for the x86 architecture. The tutorial uses C as the language of choice, with liberally mixed in bits of assembler. The aim is to talk you through the design and implementation decisions in making an operating system. The OS we make is monolithic in design (drivers are loaded through kernel-mode modules as opposed to user-mode programs), as this is simpler. This set of tutorials is very practical in nature. The theory is given in every section, but the majority of the tutorial deals with getting dirty and implementing the abstract ideas and mechanisms discussed everywhere. Table of contents Prerequisites To compile and run the sample code I provide requires just GCC, ld, NASM and GNU Make. There is no point, however, in just compiling and running without comprehension. Resources There are plenty of resources out there if you know where to look. RTFM!
101: How to use NFC If you’ve purchased an Android phone within the last year and a half, the chances are pretty high that your phone came with an underused piece of technology called near field communication (NFC). Until the payment gateway companies and the carriers can figure out how to get along, it’s going to be a little while before the dominant purpose for NFC chips in our phones are for secure payments. Before we are paying all our bills with our phones, there are still many uses for NFC, you just need to know how to unlock its potential. If you’re trying to figure out how to use NFC, you’ve come to the right place. This article will walk through how NFC is used on Android phones, how you can write your own NFC tags for use with any device (smartphone or otherwise), and explain just what NFC can be used for today. NFC is simpler than you think, you just have to know the basic information about how it works. Reading information stored on NFC Wondering how to actually use NFC?
Speaking UNIX: The best-kept secrets of UNIX power users If you're wondering why I'm wearing dark sunglasses, a fake moustache, and a baseball cap (featuring the logo of professional curling team, The Floating Stones), I'm on the lam. I'm dodging black remote-controlled helicopters, pasty-white systems administrators, and the combined forces of many daemons to bring you some of the best-kept secrets of UNIX® power users. Don your aluminum foil hat and read on. Save the environment variables Most UNIX users amass settings in shell startup files, such as .bashrc (for the Bash shell) and .zshrc (for the Z shell), to recreate a preferred shell environment time and again. Like the shell, you can customize many other UNIX applications through environment variables. For example, the pager utility less defines a number of useful environment variables: The environment variable LESS stores command-line options, reducing what you type each time you invoke the pager. Back to top Dotting the landscape At the other extreme, consider fetchmail. !!
Unison File Synchronizer Unison is a file-synchronization tool for OSX, Unix, and Windows. It allows two replicas of a collection of files and directories to be stored on different hosts (or different disks on the same host), modified separately, and then brought up to date by propagating the changes in each replica to the other. Unison shares a number of features with tools such as configuration management packages (CVS, PRCS, Subversion, BitKeeper, etc.), distributed filesystems (Coda, etc.), uni-directional mirroring utilities (rsync, etc.), and other synchronizers (Intellisync, Reconcile, etc). However, there are several points where it differs: Unison runs on both Windows and many flavors of Unix (Solaris, Linux, OS X, etc.) systems.
How to disable SSH host key checking Remote login using the SSH protocol is a frequent activity in today's internet world. With the SSH protocol, the onus is on the SSH client to verify the identity of the host to which it is connecting. The host identify is established by its SSH host key. Typically, the host key is auto-created during initial SSH installation setup. By default, the SSH client verifies the host key against a local file containing known, trustworthy machines. When you login to a remote host for the first time, the remote host's host key is most likely unknown to the SSH client. $ ssh peter@192.168.0.100The authenticity of host '192.168.0.100 (192.168.0.100)' can't be established.RSA key fingerprint is 3f:1b:f4:bd:c5:aa:c1:1f:bf:4e:2e:cf:53:fa:d8:59.Are you sure you want to continue connecting (yes/no)? If your answer is yes, the SSH client continues login, and stores the host key locally in the file ~/.ssh/known_hosts. There are multiple possible reasons why the remote host key changed.
string - Getting different output with printf and cout - C++ The Linux Graphics Stack | Clean Rinse This is an introductory overview post for the Linux Graphics Stack, and how it currently all fits together. I initially wrote it for myself after having conversations with people like Owen Taylor, Ray Strode and Adam Jackson about this stack. I had to go back to them every month or so and learn the stuff from the ground up all over again, as I had forgotten every single piece. I asked them for a good high-level overview document so I could stop bothering them. They didn’t know of any. I started this one. Also, I want to point out that a large amount of this stack applies only to the free software drivers. If you have any questions, or if at any point things were unclear, or if I’m horribly, horribly wrong about something, or if I just botched a sentence so that it’s incomprehensible, please ask me or let me know in the comments section below. To start us off, I’m going to paste the entire big stack right here, to let you get a broad overview of where every piece fits in the stack. Xlib