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• Communication between state machines with hidden transitions

  - by slartibartfast

  The question emerged for me in embedded programming but I think it can be applied to quite a number of general networking situations e.g. when a communication partner fails. Assume we have an application logic (a program) running on a computer and a gadget connected to that computer via e.g. a serial interface like RS232. The gadget has a red/green/blue LED and a button which disables the LED. The LEDs color can be driven by software commands over the serial interface and the state (red/green/blue/off) is read back and causes a reaction in the application logic. Asynchronous behaviour of the application logic with regard to the LED color down to a certain delay (depending on the execution cycle of the application) is tolerated. What we essentially have is a resource (the LED) which can not be reserved and handled atomically by software because the (organic) user can at any time press the button to interfere/break the software attempt to switch the LED color. Stripping this example from its physical outfit I dare to say that we have two communicating state machines A (application logic) and G (gadget) where G executes state changes unbeknownst to A (and also the other way round, but this is not significant in our example) and only A can be modified at a reasonable price. A needs to see the reaction and state of G in one piece of information which may be (slightly) outdated but not inconsistent with respect to the short time window when this information was generated on the side of G. What I am looking for is a concise method to handle such a situation in embedded software (i.e. no layer/framework like CORBA etc. available). A programming technique which is able to map the complete behaviour of both participants on classical interfaces of a classical programming language (C in this case). To complicate matters (or rather, to generalize), a simple high frequency communication cycle of A to G and back (IOW: A is rapidly polling G) is out of focus because of technical restrictions (delay of serial com, A not always active, etc.). What I currently see as a general solution is: the application logic A as one thread of execution an adapter object (proxy) PG (presenting G inside the computer), together with the serial driver as another thread a communication object between the two (A and PG) which is transactionally safe to exchange The two execution contexts (threads) on the computer may be multi-core or just interrupt driven or tasks in an RTOS. The com object contains the following data: suspected state (written by A): effectively a member of the power set of states in G (in our case: red, green, blue, off, red_or_green, red_or_blue, red_or_off...etc.) command data (written by A): test_if_off, switch_to_red, switch_to_green, switch_to_blue operation status (written by PG): operation_pending, success, wrong_state, link_broken new state (written by PG): red, green, blue, off The idea of the com object is that A writes whichever (set of) state it thinks G is in, together with a command. (Example: suspected state="red_or_green", command: "switch_to_blue") Notice that the commands issued by A will not work if the user has switched off the LED and A needs to know this. PG will pick up such a com object and try to send the command to G, receive its answer (or a timeout) and set the operation status and new state accordingly. A will take back the oject once it is no longer at operation_pending and can react to the outcome. The com object could be separated of course (into two objects, one for each direction) but I think it is convenient in nearly all instances to have the command close to the result. I would like to have major flaws pointed out or hear an entirely different view on such a situation.

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• Come up with a real-world problem in which only the best solution will do (a problem from Introduction to algorithms) [closed]

  - by Mike

  EDITED (I realized that the question certainly needs a context) The problem 1.1-5 in the book of Thomas Cormen et al Introduction to algorithms is: "Come up with a real-world problem in which only the best solution will do. Then come up with one in which a solution that is “approximately” the best is good enough." I'm interested in its first statement. And (from my understanding) it is asked to name a real-world problem where only the exact solution will work as opposed to a real-world problem where good-enough solution will be ok. So what is the difference between the exact and good enough solution. Consider some physics problem for example the simulation of the fulid flow in the permeable medium. To make this simulation happen some simplyfing assumptions have to be made when deriving a mathematical model. Otherwise the model becomes at least complex and unsolvable. Virtually any particle in the universe has its influence on the fluid flow. But not all particles are equal. Those that form the permeable medium are much more influental than the ones located light years away. Then when the mathematical model needs to be solved an exact solution can rarely be found unless the mathematical model is simple enough (wich probably means the model isn't close to reality). We take an approximate numerical method and after hours of coding and days of verification come up with the program or algorithm which is a solution. And if the model and an algorithm give results close to a real problem by some degree that is good enough soultion. Its worth noting the difference between exact solution algorithm and exact computation result. When considering real-world problems and real-world computation machines I believe all physical problems solutions where any calculations are taken can not be exact because universal physical constants are represented approximately in the computer. Any numbers are represented with the limited precision, at least limited by amount of memory available to computing machine. I can imagine plenty of problems where good-enough, good to some degree solution will work, like train scheduling, automated trading, satellite orbit calculation, health care expert systems. In that cases exact solutions can't be derived due to constraints on computation time, limitations in computer memory or due to the nature of problems. I googled this question and like what this guy suggests: there're kinds of mathematical problems that need exact solutions (little note here: because the question is taken from the book "Introduction to algorithms" the term "solution" means an algorithm or a program, which in this case gives exact answer on each input). But that's probably more of theoretical interest. So I would like to narrow down the question to: What are the real-world practical problems where only the best (exact) solution algorithm or program will do (but not the good-enough solution)? There are problems like breaking of cryptographic ciphers where only exact solution matters in practice and again in practice the process of deciphering without knowing a secret should take reasonable amount of time. Returning to the original question this is the problem where good-enough (fast-enough) solution will do there's no practical need in instant crack though it's desired. So the quality of "best" can be understood in any sense: exact, fastest, requiring least memory, having minimal possible network traffic etc. And still I want this question to be theoretical if possible. In a sense that there may be example of computer X that has limited resource R of amount Y where the best solution to problem P is the one that takes not more than available Y for inputs of size N*Y. But that's the problem of finding solution for P on computer X which is... well, good enough. My final thought that we live in a world where it is required from programming solutions to practical purposes to be good enough. In rare cases really very very good but still not the best ones. Isn't it? :) If it's not can you provide an example? Or can you name any such unsolved problem of practical interest?

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• Is FPGA course useful for a CS student?

  - by Rajeev

  I am a 3rd year computer science engineering student.Is it beneficial for me to go for FPGA course or seminar?

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• Creating a CD-burning feature for a music player based on Java

  - by jjanggoo

  Hi, I'm trying to create a CD-burning feature for a Java-based music player for my school project. Since I'm new to real-life programming (I've only learned to write codes on AP Computer Science A level), I don't know how I can apply the concepts I learned from APCS A to this task. A friend of mine who is studying computer science at graduate school told me to "look up the cd player control functions and add methods in those classes to read in data that you want to write to the CD, write it to a buffer, write everything in the buffer to the CD itself, clear the buffer and then write a new chunk of data into the buffer," but I can't quite grasp what this means, and tt's really hard to contact her right now because she's busy working on her dissertation. Can someone from this forum please guide me through & explain the general concepts? Thank you!

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• Desktop Notifications, aka Internal Alert System

  - by Refracted Paladin

  It has become apparent that where I work needs, internally, a "notification system". The issue being that we are very spread out throughout multiple buildings and the bulk of the work force regularly keeps there email closed for hours at a time. I need to create a simple way to be able to push out a message and have it "pop up" on everyones computer(or a single computer). My first thought was to write a windows service that calls a winform/wpf app that resides on each computer that simply pops up with the message. Not sure how viable an idea that is but this is just brain-storming. A different route, I thought, could be an app that resides in the systray on each computer that polls a db table and using the Query Notifications could pop up a message each time a new row is added. Then simply create an insanely basic app for writing a row to that table. So, what I am asking is if any one else has walked this path. If so, how? What things did you take into consideration? Are either of my ideas valid starting points or are "egg and my face in perfect alignment"? Is there a different way that is even simpler? Thanks

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• Best Fit Scheduling Algorithm

  - by Teegijee

  I'm writing a scheduling program with a difficult programming problem. There are several events, each with multiple meeting times. I need to find an arrangement of meeting times such that each schedule contains any given event exactly once, using one of each event's multiple meeting times. Obviously I could use brute force, but that's rarely the best solution. I'm guessing this is a relatively basic computer science problem, which I'll learn about once I am able to start taking computer science classes. In the meantime, I'd prefer any links where I could read up on this, or even just a name I could Google.

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• running bash scripts in php

  - by HDawg

  I have two computers. On the first computer I have apache running with all my web code. On the second computer I have large amounts of data stored with a retrieval script (the script usually takes hours to run). I am essentially creating a web UI to access this data without any time delay. so I call: exec("bash initial.bash"); this is a driver script that is in my Apache folder. It calls the script on the other computer. calling: ssh otherMachine temp.bash& this script invokes the data retrieval script on the second computer. If I call initial.bash in the terminal, everything works smoothly and successfully, but if I call it in my PHP file, then all my commands in initial.bash run, with the exception of ssh otherMachine temp.bash&. I put the & at the end of that, so that temp.bash will run in the background, since it does take a few hours to complete. I am not sure why the nested script is not running when invoked by Apache. Is there a better alternative than using exec or shell_exec to call a script, which ultimately calls another script. The reason I don't call a script on the second machine directly is because of the time it takes the program to run. Shell_exec does not render the php page until the script is complete.

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• can't properly shutdown ubuntu and sound problem on HP mini 311 netbook

  - by Viele

  hi, I recently bought a HP mini 311 netbook. I replaced its harddrive and installed ubuntu 10.04. Since then, I have encountered some very strange problem with its sound and shutdown/reboot. At times, when I start the computer, it will have no sound, on the GUI the sound is at max, but no sound is available. This sometimes also happen after after upgrades, hibernate, and toggling the wireless radio button. Strangely, when the sound is out the device will also refuse to be shutdown. If I shutdown the computer using the GUI, it will simply go back to the log in screen without actually shutting down. If I use "sudo shutdown 0", the computer will hang on the loading screen of the shut down process. I had to force the pc to shutdown by holding the power button down. usually (probably always) after I force a turn-off then start off again. the sound and shutdown become normal. I wonder if anyone have clues regarding to the cause of this problem. This the info about the computer: 1) installed ubuntu 10.04LTS RC, later upgraded to formal released version. 2) cat /proc/asound/version == "Advanced Linux Sound Architecture Driver Version 1.0.21." however, when doing 'alsaconf' the version displayed is 1.0.23 any help is appreciated. Thanks

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• SQL to retrieve aggregated data with computed columns

  - by Remnant

  I have a table that looks like this for about ~30 students: StudentID Course* CourseStatus 1 Math Pass 1 English Fail 1 Science Pass 2 Math Fail 2 English Pass 2 Science Fail etc. *In my actual database the 'Course' column is a CourseID e.g. (1 = Math; 2 = English etc.) which references a 'CourseName' table. I amended the table above just to make it clear the nature of the problem. I want to write a query (stored procedure) in SQL that summarises performance for a given course and returns the following: EXEC usp_GetCourseSummary 'Math' Total Students Total Pass % Pass Total Fail % Fail 25 15 60 10 40 Have been scratching my head on this one for some time. Any ideas?

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• Best Fit Scheduling Algorithim

  - by Teegijee

  I'm writing a scheduling program with a difficult programming problem. There are several events, each with multiple meeting times. I need to find an arrangement of meeting times such that each schedule contains any given event exactly once, using one of each event's multiple meeting times. Obviously I could use brute force, but that's rarely the best solution. I'm guessing this is a relatively basic computer science problem, which I'll learn about once I am able to start taking computer science classes. In the meantime, I'd prefer any links where I could read up on this, or even just a name I could Google.

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• Is it the right time to get a Master's degree?

  - by harshit

  I'm currently a software engineer in India and have been working for 3,5 years. Before recession started I decided to study further and planned for a Master of Science degree in computer science in Fall09, since I want to explore more of this field. I have got an admission in Univ of Texas @ Dallas. I am confused about whether I should go for studying at the time of recession or not and how the market will be once I graduate in 2011 Jan. Any views will be appreciated.

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• Pong: How does the paddle know where the ball will hit?

  - by Roflcoptr

  After implementing Pacman and Snake I'm implementing the next very very classic game: Pong. The implementation is really simple, but I just have one little problem remaining. When one of the paddle (I'm not sure if it is called paddle) is controlled by the computer, I have trouble to position it at the correct position. The ball has a current position, a speed (which for now is constant) and a direction angle. So I could calculate the position where it will hit the side of the computer controlled paddle. And so Icould position the paddle right there. But however in the real game, there is a probability that the computer's paddle will miss the ball. How can I implement this probability? If I only use a probability of lets say 0.5 that the computer's paddle will hit the ball, the problem is solved, but I think it isn't that simple. From the original game I think the probability depends on the distance between the current paddle position and the position the ball will hit the border. Does anybody have any hints how exactly this is calculated?

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• mysql fetch result parent id and category id by single query?

  - by Karthik

  I have the table and values like this, CREATE TABLE `category` ( `id` INT( 4 ) NOT NULL AUTO_INCREMENT PRIMARY KEY , `category` VARCHAR( 50 ) NOT NULL , `parent` INT( 4 ) NOT NULL ) INSERT INTO `category` VALUES (1, 'MCA', 9); INSERT INTO `category` VALUES (2, 'M Tech', 9); INSERT INTO `category` VALUES (3, 'B Tech', 9); INSERT INTO `category` VALUES (4, 'BioTech', 9); INSERT INTO `category` VALUES (5, 'InfoTech', 9); INSERT INTO `category` VALUES (6, 'Chemical', 10); INSERT INTO `category` VALUES (7, 'Indus', 10); INSERT INTO `category` VALUES (8, 'Physics', 10); INSERT INTO `category` VALUES (9, 'Information Science', 0); INSERT INTO `category` VALUES (10, 'Others Science', 0); I need a single query for getting the values in terms of category and subcategory. 3rd values zero as category and others are subcategory.

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• Need help on how to begin learning website development

  - by Golfy

  OK for the past 10 days I have been trying to figure out where to begin learning website development a dynamic one, So far everyone told me you should start with computer science and I am like What the @#$% how am I suppose to learn computer science without going to school and get a degree but I don't want a degree I just want to learn how to devlope websites. So now I am here and confused about how to put together a website. I get HTML and CSS but still have some problems designing the site now on the other had I am having trouble trying to figure out how php and database mysql is used to put together a website. I have seen videos from lynda.com and still have no Idea after I have watched the video the basic one, one that teach you the Variables, Loops, Strings ext... ok than what happens, how do you build the website with it, that is the question I am real not understand the answer to. Any help will be appreciated.

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• Differences between Assembly Code output of the same program

  - by ultrajohn

  I have been trying to replicate the buffer overflow example3 from this article aleph one I'm doing this as a practice for a project in a computer security course i'm taking so please, I badly need your help. I've been the following the example, performing the tasks as I go along. My problem is the assembly code dumped by gdb in my computer (i'm doing this on a debian linux image running on VM Ware) is different from that of the example in the article. There are some constructs which I find confusing. Here is the one from my computer: here is the one from the article... Dump of assembler code for function main: 0x8000490 <main>: pushl %ebp 0x8000491 <main+1>: movl %esp,%ebp 0x8000493 <main+3>: subl $0x4,%esp 0x8000496 <main+6>: movl $0x0,0xfffffffc(%ebp) 0x800049d <main+13>: pushl $0x3 0x800049f <main+15>: pushl $0x2 0x80004a1 <main+17>: pushl $0x1 0x80004a3 <main+19>: call 0x8000470 <function> 0x80004a8 <main+24>: addl $0xc,%esp 0x80004ab <main+27>: movl $0x1,0xfffffffc(%ebp) 0x80004b2 <main+34>: movl 0xfffffffc(%ebp),%eax 0x80004b5 <main+37>: pushl %eax 0x80004b6 <main+38>: pushl $0x80004f8 0x80004bb <main+43>: call 0x8000378 <printf> 0x80004c0 <main+48>: addl $0x8,%esp 0x80004c3 <main+51>: movl %ebp,%esp 0x80004c5 <main+53>: popl %ebp 0x80004c6 <main+54>: ret 0x80004c7 <main+55>: nop As you can see, there are differences between the two. I'm confuse and I can't understand totally the assembly code from my computer. I would like to know the differences between the two. How is pushl different from push, mov vs movl , and so on... what does the expression 0xhexavalue(%register) means? I am sorry If I'm asking a lot, But I badly need your help. Thanks for the help really...

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• What is recursion? -- In plain english.

  - by Christopher Altman

  I hear this word everyday, but cannot give a meaningful, concise, or plain-english answer to what it is. Recursion is defined by the bastian of knowledge as: Recursion in computer science is a method where the solution to a problem depends on solutions to smaller instances of the same problem.1 The approach can be applied to many types of problems, and is one of the central ideas of computer science.[2] Source Is recursion simply something that repeats itself to get a solution? I am looking for a "Recursion for Dummies" definition, and maybe simple examples. My goal is to be able to understand and explain recursion in my own words. I do not like simply thinking I know the meaning of something because I hear it referenced daily, but have not paused to form my own understanding.

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• Please help me in creating a update query

  - by Rajesh Rolen- DotNet Developer

  I have got a table which contains 5 column and query requirements: update row no 8 (or id=8) set its column 2, column 3's value from id 9th column 2, column 3 value. means all value of column 2, 3 should be shifted to column 2, 3 of upper row (start from row no 8) and value of last row's 2, 3 will be null For example, with just 3 rows, the first row is untouched, the second to N-1th rows are shifted once, and the Nth row has nulls. id math science sst hindi english 1 11 12 13 14 15 2 21 22 23 24 25 3 31 32 33 34 35 The result of query of id=2 should be: id math science sst hindi english 1 11 12 13 14 15 2 31 32 23 24 25 //value of 3rd row (col 2,3) shifted to row 2 3 null null 33 34 35 This process should run for all rows whose id 2 Please help me to create this update query I am using MS sqlserver 2005

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• What to see in India as a developer and student

  - by lasseespeholt

  Hi, I'm planning a trip to India around July-August. And I want to hear Indian developers or developers traveled to India if there are something interesting to see in India (around Bombay) for developers in general. Maybe a conference etc. I have looked at http://www.conferencealerts.com/computing.htm I have studied computer science in a year now but have been a spare time and independent developer for some years now. Furthermore, I have tried finding summer courses but that is properly too late now and computer science summer courses is hard to find in India. Best regards, Lasse Espeholt

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• What is it about Fibonacci numbers?

  - by Ian Bishop

  Fibonacci numbers have become a popular introduction to recursion for Computer Science students and there's a strong argument that they persist within nature. For these reasons, many of us are familiar with them. They also exist within Computer Science elsewhere too; in surprisingly efficient data structures and algorithms based upon the sequence. There are two main examples that come to mind: Fibonacci heaps which have better amortized running time than binomial heaps. Fibonacci search which shares O(log N) running time with binary search on an ordered array. Is there some special property of these numbers that gives them an advantage over other numerical sequences? Is it a density quality? What other possible applications could they have? It seems strange to me as there are many natural number sequences that occur in other recursive problems, but I've never seen a Catalan heap.

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• Please help me in creating an update query

  - by Rajesh Rolen- DotNet Developer

  I have got a table which contains 5 column and query requirements: update row no 8 (or id=8) set its column 2, column 3's value from id 9th column 2, column 3 value. means all value of column 2, 3 should be shifted to column 2, 3 of upper row (start from row no 8) and value of last row's 2, 3 will be null For example, with just 3 rows, the first row is untouched, the second to N-1th rows are shifted once, and the Nth row has nulls. id math science sst hindi english 1 11 12 13 14 15 2 21 22 23 24 25 3 31 32 33 34 35 The result of query of id=2 should be: id math science sst hindi english 1 11 12 13 14 15 2 31 32 23 24 25 //value of 3rd row (col 2,3) shifted to row 2 3 null null 33 34 35 This process should run for all rows whose id 2 Please help me to create this update query I am using MS sqlserver 2005

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• Would the world be a better place if there were only one programming language?

  - by Simon

  Well, perhaps not the world, but would it encourage more-re-use, less replication of basic code, or at least an uplift in what is considered basic code, more time advancing the application science and a greater encouragement to share, a more advanced base of understanding for new programmers, since the language could be taught ubiquitously and patterns of teaching would have emerged which were optimised for students learning etc etc? I think all of those things would make the programming world better and would probably have significant commercial benefit too. This is definitely not a religious debate about which language is best, and is predicated on the notion of some super-being having designed the perfect language to start with, which was improbable, but it strikes me that if, from the beginning, there were only a single programming language we may be further along in terms of the evolution of the software industry and software science. And although it is now impossible, if you buy some or all of these assertions is there an argument for standardising on a single language for the future so we can accelerate our collective progress rather than all of us re-inventing some part of the same wheel and consigning our children to the same fate?

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• Scan a Windows PC for Viruses from a Ubuntu Live CD

  - by Trevor Bekolay

  Getting a virus is bad. Getting a virus that causes your computer to crash when you reboot is even worse. We’ll show you how to clean viruses from your computer even if you can’t boot into Windows by using a virus scanner in a Ubuntu Live CD. There are a number of virus scanners available for Ubuntu, but we’ve found that avast! is the best choice, with great detection rates and usability. Unfortunately, avast! does not have a proper 64-bit version, and forcing the install does not work properly. If you want to use avast! to scan for viruses, then ensure that you have a 32-bit Ubuntu Live CD. If you currently have a 64-bit Ubuntu Live CD on a bootable flash drive, it does not take long to wipe your flash drive and go through our guide again and select normal (32-bit) Ubuntu 9.10 instead of the x64 edition. For the purposes of fixing your Windows installation, the 64-bit Live CD will not provide any benefits. Once Ubuntu 9.10 boots up, open up Firefox by clicking on its icon in the top panel. Navigate to http://www.avast.com/linux-home-edition. Click on the Download tab, and then click on the link to download the DEB package. Save it to the default location. While avast! is downloading, click on the link to the registration form on the download page. Fill in the registration form if you do not already have a trial license for avast!. By the time you’ve filled out the registration form, avast! will hopefully be finished downloading. Open a terminal window by clicking on Applications in the top-left corner of the screen, then expanding the Accessories menu and clicking on Terminal. In the terminal window, type in the following commands, pressing enter after each line. cd Downloadssudo dpkg –i avast* This will install avast! on the live Ubuntu environment. To ensure that you can use the latest virus database, while still in the terminal window, type in the following command: sudo sysctl –w kernel.shmmax=128000000 Now we’re ready to open avast!. Click on Applications on the top-left corner of the screen, expand the Accessories folder, and click on the new avast! Antivirus item. You will first be greeted with a window that asks for your license key. Hopefully you’ve received it in your email by now; open the email that avast! sends you, copy the license key, and paste it in the Registration window. avast! Antivirus will open. You’ll notice that the virus database is outdated. Click on the Update database button and avast! will start downloading the latest virus database. To scan your Windows hard drive, you will need to “mount” it. While the virus database is downloading, click on Places on the top-left of your screen, and click on your Windows hard drive, if you can tell which one it is by its size. If you can’t tell which is the correct hard drive, then click on Computer and check out each hard drive until you find the right one. When you find it, make a note of the drive’s label, which appears in the menu bar of the file browser. Also note that your hard drive will now appear on your desktop. By now, your virus database should be updated. At the time this article was written, the most recent version was 100404-0. In the main avast! window, click on the radio button next to Selected folders and then click on the “+” button to the right of the list box. It will open up a dialog box to browse to a location. To find your Windows hard drive, click on the “>” next to the computer icon. In the expanded list, find the folder labelled “media” and click on the “>” next to it to expand it. In this list, you should be able to find the label that corresponds to your Windows hard drive. If you want to scan a certain folder, then you can go further into this hierarchy and select that folder. However, we will scan the entire hard drive, so we’ll just press OK. Click on Start scan and avast! will start scanning your hard drive. If a virus is found, you’ll be prompted to select an action. If you know that the file is a virus, then you can Delete it, but there is the possibility of false positives, so you can also choose Move to chest to quarantine it. When avast! is done scanning, it will summarize what it found on your hard drive. You can take different actions on those files at this time by right-clicking on them and selecting the appropriate action. When you’re done, click Close. Your Windows PC is now free of viruses, in the eyes of avast!. Reboot your computer and with any luck it will now boot up! Alternatives to avast! If avast! and a liberal amount of Googling doesn’t fix your problem, it’s possible that a different virus scanner will fix your obscure issue. Here are a list of other virus scanners available for Ubuntu that are either free or offer free trials. See their support forums for help on installing these virus scanners. Avira AntiVir Personal for Linux / Solaris Panda Antivirus for Linux Installation and usage guide from Ubuntu F-PROT Antivirus for Linux ClamAV installation and usage guide from Ubuntu NOD32 Antivirus for Linux Kaspersky Anti-Virus 2010 Bitdefender Antivirus for Unices Conclusion Running avast! from a Ubuntu Live CD can clean the vast majority of viruses from your Windows PC. This is another reason to always have a Ubuntu Live CD ready just in case something happens to your Windows installation! Similar Articles Productive Geek Tips Secure Computing: Windows Live OneCareHow To Remove Antivirus Live and Other Rogue/Fake Antivirus MalwareUse the Windows Key for the "Start" Menu in Ubuntu LinuxScan Files for Viruses Before You Download With Dr.WebAsk the Readers: Share Your Tips for Defeating Viruses and Malware TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 The Ultimate Guide For YouTube Lovers Will it Blend? iPad Edition Penolo Lets You Share Sketches On Twitter Visit Woolyss.com for Old School Games, Music and Videos Add a Custom Title in IE using Spybot or Spyware Blaster When You Need to Hail a Taxi in NYC

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• Week in Geek: US Govt E-card Scam Siphons Confidential Data Edition

  - by Asian Angel

  This week we learned how to “back up photos to Flickr, automate repetitive tasks, & normalize MP3 volume”, enable “stereo mix” in Windows 7 to record audio, create custom papercraft toys, read up on three alternatives to Apple’s flaky iOS alarm clock, decorated our desktops & app docks with Google icon packs, and more. Photo by alexschlegel. Random Geek Links It has been a busy week on the security & malware fronts and we have a roundup of the latest news to help keep you updated. Photo by TopTechWriter.US. US govt e-card scam hits confidential data A fake U.S. government Christmas e-card has managed to siphon off gigabytes of sensitive data from a number of law enforcement and military staff who work on cybersecurity matters, many of whom are involved in computer crime investigations. Security tool uncovers multiple bugs in every browser Michal Zalewski reports that he discovered the vulnerability in Internet Explorer a while ago using his cross_fuzz fuzzing tool and reported it to Microsoft in July 2010. Zalewski also used cross_fuzz to discover bugs in other browsers, which he also reported to the relevant organisations. Microsoft to fix Windows holes, but not ones in IE Microsoft said that it will release two security bulletins next week fixing three holes in Windows, but it is still investigating or working on fixing holes in Internet Explorer that have been reportedly exploited in attacks. Microsoft warns of Windows flaw affecting image rendering Microsoft has warned of a Windows vulnerability that could allow an attacker to take control of a computer if the user is logged on with administrative rights. Windows 7 Not Affected by Critical 0-Day in the Windows Graphics Rendering Engine While confirming that details on a Critical zero-day vulnerability have made their way into the wild, Microsoft noted that customers running the latest iteration of Windows client and server platforms are not exposed to any risks. Microsoft warns of Office-related malware Microsoft’s Malware Protection Center issued a warning this week that it has spotted malicious code on the Internet that can take advantage of a flaw in Word and infect computers after a user does nothing more than read an e-mail. *Refers to a flaw that was addressed in the November security patch releases. Make sure you have all of the latest security updates installed. Unpatched hole in ImgBurn disk burning application According to security specialist Secunia, a highly critical vulnerability in ImgBurn, a lightweight disk burning application, can be used to remotely compromise a user’s system. Hole in VLC Media Player Virtual Security Research (VSR) has identified a vulnerability in VLC Media Player. In versions up to and including 1.1.5 of the VLC Media Player. Flash Player sandbox can be bypassed Flash applications run locally can read local files and send them to an online server – something which the sandbox is supposed to prevent. Chinese auction site touts hacked iTunes accounts Tens of thousands of reportedly hacked iTunes accounts have been found on Chinese auction site Taobao, but the company claims it is unable to take action unless there are direct complaints. What happened in the recent Hotmail outage Mike Schackwitz explains the cause of the recent Hotmail outage. DOJ sends order to Twitter for Wikileaks-related account info The U.S. Justice Department has obtained a court order directing Twitter to turn over information about the accounts of activists with ties to Wikileaks, including an Icelandic politician, a legendary Dutch hacker, and a U.S. computer programmer. Google gets court to block Microsoft Interior Department e-mail win The U.S. Federal Claims Court has temporarily blocked Microsoft from proceeding with the $49.3 million, five-year DOI contract that it won this past November. Google Apps customers get email lockdown Companies and organisations using Google Apps are now able to restrict the email access of selected users. LibreOffice Is the Default Office Suite for Ubuntu 11.04 Matthias Klose has announced some details regarding the replacement of the old OpenOffice.org 3.2.1 packages with the new LibreOffice 3.3 ones, starting with the upcoming Ubuntu 11.04 (Natty Narwhal) Alpha 2 release. Sysadmin Geek Tips Photo by Filomena Scalise. How to Setup Software RAID for a Simple File Server on Ubuntu Do you need a file server that is cheap and easy to setup, “rock solid” reliable, and has Email Alerting? This tutorial shows you how to use Ubuntu, software RAID, and SaMBa to accomplish just that. How to Control the Order of Startup Programs in Windows While you can specify the applications you want to launch when Windows starts, the ability to control the order in which they start is not available. However, there are a couple of ways you can easily overcome this limitation and control the startup order of applications. Random TinyHacker Links Using Opera Unite to Send Large Files A tutorial on using Opera Unite to easily send huge files from your computer. WorkFlowy is a Useful To-do List Tool A cool to-do list tool that lets you integrate multiple tasks in one single list easily. Playing Flash Videos on iOS Devices Yes, you can play flash videos on jailbroken iPhones. Here’s a tutorial. Clear Safari History and Cookies On iPhone A tutorial on clearing your browser history on iPhone and other iOS devices. Monitor Your Internet Usage Here’s a cool, cross-platform tool to monitor your internet bandwidth. Super User Questions See what the community had to say on these popular questions from Super User this week. Why is my upload speed much less than my download speed? Where should I find drivers for my laptop if it didn’t come with a driver disk? OEM Office 2010 without media – how to reinstall? Is there a point to using theft tracking software like Prey on my laptop, if you have login security? Moving an “all-in-one” PC when turned on/off How-To Geek Weekly Article Recap Get caught up on your HTG reading with our hottest articles from this past week. How to Combine Rescue Disks to Create the Ultimate Windows Repair Disk How To Boot 10 Different Live CDs From 1 USB Flash Drive What is Camera Raw, and Why Would a Professional Prefer it to JPG? Did You Know Facebook Has Built-In Shortcut Keys? The How-To Geek Guide to Audio Editing: The Basics One Year Ago on How-To Geek Enjoy looking through our latest gathering of retro article goodness. Learning Windows 7: Create a Homegroup & Join a New Computer To It How To Disconnect a Machine from a Homegroup Use Remote Desktop To Access Other Computers On a Small Office or Home Network How To Share Files and Printers Between Windows 7 and Vista Allow Users To Run Only Specified Programs in Windows 7 The Geek Note That is all we have for you this week and we hope your first week back at work or school has gone very well now that the holidays are over. Know a great tip? Send it in to us at [email protected]. Photo by Pamela Machado. Latest Features How-To Geek ETC HTG Projects: How to Create Your Own Custom Papercraft Toy How to Combine Rescue Disks to Create the Ultimate Windows Repair Disk What is Camera Raw, and Why Would a Professional Prefer it to JPG? The How-To Geek Guide to Audio Editing: The Basics How To Boot 10 Different Live CDs From 1 USB Flash Drive The 20 Best How-To Geek Linux Articles of 2010 Arctic Theme for Windows 7 Gives Your Desktop an Icy Touch Install LibreOffice via PPA and Receive Auto-Updates in Ubuntu Creative Portraits Peek Inside the Guts of Modern Electronics Scenic Winter Lane Wallpaper to Create a Relaxing Mood Access Your Web Apps Directly Using the Context Menu in Chrome The Deep – Awesome Use of Metal Objects as Deep Sea Creatures [Video]

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• [GEEK SCHOOL] Network Security 4: Windows Firewall: Your System’s Best Defense

  - by Ciprian Rusen

  If you have your computer connected to a network, or directly to your Internet connection, then having a firewall is an absolute necessity. In this lesson we will discuss the Windows Firewall – one of the best security features available in Windows! The Windows Firewall made its debut in Windows XP. Prior to that, Windows system needed to rely on third-party solutions or dedicated hardware to protect them from network-based attacks. Over the years, Microsoft has done a great job with it and it is one of the best firewalls you will ever find for Windows operating systems. Seriously, it is so good that some commercial vendors have decided to piggyback on it! Let’s talk about what you will learn in this lesson. First, you will learn about what the Windows Firewall is, what it does, and how it works. Afterward, you will start to get your hands dirty and edit the list of apps, programs, and features that are allowed to communicate through the Windows Firewall depending on the type of network you are connected to. Moving on from there, you will learn how to add new apps or programs to the list of allowed items and how to remove the apps and programs that you want to block. Last but not least, you will learn how to enable or disable the Windows Firewall, for only one type of networks or for all network connections. By the end of this lesson, you should know enough about the Windows Firewall to use and manage it effectively. What is the Windows Firewall? Windows Firewall is an important security application that’s built into Windows. One of its roles is to block unauthorized access to your computer. The second role is to permit authorized data communications to and from your computer. Windows Firewall does these things with the help of rules and exceptions that are applied both to inbound and outbound traffic. They are applied depending on the type of network you are connected to and the location you have set for it in Windows, when connecting to the network. Based on your choice, the Windows Firewall automatically adjusts the rules and exceptions applied to that network. This makes the Windows Firewall a product that’s silent and easy to use. It bothers you only when it doesn’t have any rules and exceptions for what you are trying to do or what the programs running on your computer are trying to do. If you need a refresher on the concept of network locations, we recommend you to read our How-To Geek School class on Windows Networking. Another benefit of the Windows Firewall is that it is so tightly and nicely integrated into Windows and all its networking features, that some commercial vendors decided to piggyback onto it and use it in their security products. For example, products from companies like Trend Micro or F-Secure no longer provide their proprietary firewall modules but use the Windows Firewall instead. Except for a few wording differences, the Windows Firewall works the same in Windows 7 and Windows 8.x. The only notable difference is that in Windows 8.x you will see the word “app” being used instead of “program”. Where to Find the Windows Firewall By default, the Windows Firewall is turned on and you don’t need to do anything special in order for it work. You will see it displaying some prompts once in a while but they show up so rarely that you might forget that is even working. If you want to access it and configure the way it works, go to the Control Panel, then go to “System and Security” and select “Windows Firewall”. Now you will see the Windows Firewall window where you can get a quick glimpse on whether it is turned on and the type of network you are connected to: private networks or public network. For the network type that you are connected to, you will see additional information like: The state of the Windows Firewall How the Windows Firewall deals with incoming connections The active network When the Windows Firewall will notify you You can easily expand the other section and view the default settings that apply when connecting to networks of that type. If you have installed a third-party security application that also includes a firewall module, chances are that the Windows Firewall has been disabled, in order to avoid performance issues and conflicts between the two security products. If that is the case for your computer or device, you won’t be able to view any information in the Windows Firewall window and you won’t be able to configure the way it works. Instead, you will see a warning that says: “These settings are being managed by vendor application – Application Name”. In the screenshot below you can see an example of how this looks. How to Allow Desktop Applications Through the Windows Firewall Windows Firewall has a very comprehensive set of rules and most Windows programs that you install add their own exceptions to the Windows Firewall so that they receive network and Internet access. This means that you will see prompts from the Windows Firewall on occasion, generally when you install programs that do not add their own exceptions to the Windows Firewall’s list. In a Windows Firewall prompt, you are asked to select the network locations to which you allow access for that program: private networks or public networks. By default, Windows Firewall selects the checkbox that’s appropriate for the network you are currently using. You can decide to allow access for both types of network locations or just to one of them. To apply your setting press “Allow access”. If you want to block network access for that program, press “Cancel” and the program will be set as blocked for both network locations. At this step you should note that only administrators can set exceptions in the Windows Firewall. If you are using a standard account without administrator permissions, the programs that do not comply with the Windows Firewall rules and exceptions are automatically blocked, without any prompts being shown. You should note that in Windows 8.x you will never see any Windows Firewall prompts related to apps from the Windows Store. They are automatically given access to the network and the Internet based on the assumption that you are aware of the permissions they require based on the information displayed by the Windows Store. Windows Firewall rules and exceptions are automatically created for each app that you install from the Windows Store. However, you can easily block access to the network and the Internet for any app, using the instructions in the next section. How to Customize the Rules for Allowed Apps Windows Firewall allows any user with an administrator account to change the list of rules and exceptions applied for apps and desktop programs. In order to do this, first start the Windows Firewall. On the column on the left, click or tap “Allow an app or feature through Windows Firewall” (in Windows 8.x) or “Allow a program or feature through Windows Firewall” (in Windows 7). Now you see the list of apps and programs that are allowed to communicate through the Windows Firewall. At this point, the list is grayed out and you can only view which apps, features, and programs have rules that are enabled in the Windows Firewall.

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• Week in Geek: IPv6 Capable Smartphones Compromise User Privacy Edition

  - by Asian Angel

  This week we learned how to “clone a disk, resize static windows, and create system function shortcuts”, use 45 different services, sites, and apps to help read favorite sites, add MP3 support to Audacity (for saving in MP3 format), install a Wii game loader for easy backups and fast load times, create a Blue Screen of Death in any color, and more. Photo by legofenris. Weekly News Links Photo by The H Security. IPv6: Smartphones compromise users’ privacy Since version 4 of the iOS operating system, Apple’s iPhones, iPads and iPods have been capable of handling IPv6, and most Android devices have been capable since version 2.1. However, the operating systems transfer an ID that discloses information about their users. Dumb phones can be attacked too Much of the discussion of security threats to mobile phones revolves around smartphones, but researchers have found that less advanced “feature phones,” still used by the majority of people around the world, also are vulnerable to attack. SCADA exploit – the dragon awakes The recent publication of an exploit for KingView, a software package for visualising industrial process control systems, appears to be having an effect. Threatpost reports that both the Chinese vendor Wellintech and Chinese CERT (CN-CERT) have now reacted. Sophos: Spam to get more malicious Spam is becoming more malicious in nature as trickery tactics change in line with current user interests, according to a new report released Tuesday by Sophos. Global spam traffic rebounds as Rustock wakes Spam is on the rise after the Rustock botnet awoke from its Christmas slumber, according to Symantec. Cracking WPA keys in the cloud At the forthcoming Black Hat conference, blogger Thomas Roth plans to demonstrate how weak WPA PSKs can be cracked quickly and easily using Amazon’s Elastic Compute Cloud (EC2) service. Microsoft Security Advisory: Vulnerability in Internet Explorer could allow remote code execution Provides a link to more details about the vulnerability and shows a work-around/fix for the problem. Adobe plans to make it easier to delete Flash cookies in web browsers The new API, NPAPI:ClearSiteData, will allow Flash cookies – also known as Local Shared Objects (LSO) – to be deleted directly in the browser’s settings. Firefox beta getting new database standard The ninth beta version of Firefox is set to get support for a standard called IndexedDB that provides a database interface useful for offline data storage and other tasks needing information on a browser’s computer. MetroPCS accused of blocking certain Net content MetroPCS is violating the FCC’s recently approved Net neutrality rules by blocking certain Internet content, say several public interest groups. Server and Tools chief Muglia to leave Microsoft in summer 2011 Microsoft veteran and Server & Tools Business (STB) President Bob Muglia is leaving Microsoft, according to an email that CEO Steve Ballmer sent to employees on January 10. Report: DOJ nearing decision on Google-ITA The U.S. Department of Justice is gearing up for a possible formal antitrust investigation into whether or not Google should be allowed to purchase travel software company ITA Software, according to a report. South Korea says Google Street View broke law Police in South Korea reportedly say Google broke the country’s law when its Street View service captured personal data from unsecure Wi-Fi networks. The backlash over Google’s HTML5 video bet Choosing strategies based on what you believe to be long-term benefits is generally a good idea when running a business, but if you manage to alienate the world in the process, the long term may become irrelevant. Google answers critics on HTML5 Web video move Google responded to critics of its decision to drop support for a popular HTML5 video codec by declaring that a royalty-supported standard for Web video will hold the Web hostage. Random TinyHacker Links A Special GiveAway: a Great Book & Great Security Software The team from 7 Tutorials has a special giveaway running during the month of January. Signed copies of their latest book, full 1-year licenses of BitDefender Internet Security 2011 and free 3-month trials for everyone willing to participate. One Click Rooting For Android Phones Here’s a nice tool that helps you root your Android phone effortlessly. New Angry Birds Free version 1.0 Available in the App Store. Google Code University Learn programming at Google Code University. Capture and Share Your Favorite Part Of a YouTube Video SnipSnip.it lets you share only the part of the video that you like. Super User Questions More great questions and answers from this past week’s popular topics at Super User. What are the Windows A: and B: drives used for? Does OS X support linux-like features? What is the easiest way to make a backup of an entire hard disk? Will shifting from Wireless to Wired network result in better performance? Is it legal to install Windows 7 Home Premium Retail inside VMware virtual machine? How-To Geek Weekly Article Recap Enjoy reading through our hottest articles from this past week. The 50 Best Ways to Disable Built-in Windows Features You Don’t Want The Best of CES (Consumer Electronics Show) in 2011 How to Upgrade Windows 7 Easily (And Understand Whether You Should) The Worst of CES (Consumer Electronics Show) in 2011 The How-To Geek Guide to Audio Editing: Basic Noise Removal One Year Ago on How-To Geek More great articles from one year ago filled with helpful geeky goodness for you to enjoy. Share Text & Images the Easy Way with JustPaste.it Start Portable Firefox in Safe Mode Firefox 3.6 Release Candidate Available, Here’s How to Fix Your Incompatible Extensions Protect Your Computer from “Little Hands” with KidSafe Lock Prying Eyes Out of Your Minimized Windows Custom Crocheted Cylon-Cthulhu Hybrid What happens when you let your Cylon Centurion figure and your crocheted Cthulhu spend too many lonely nights together? A Cylon-Cthulhu hybrid, of course! You can get your own from the Cthulhu Chick store over on Etsy. Note: This is not an ad…Ruth is a friend of ours, and this Cylon-Cthulhu hybrid makes the perfect guard for the new MVP trophy in our office. The Geek Note Whether it is a geeky indoor project or just getting outside, we hope that you and your families have a terrific fun-filled weekend! Remember to keep sending those great tips in to us at [email protected]. Photo by qwrrty. Latest Features How-To Geek ETC How to Upgrade Windows 7 Easily (And Understand Whether You Should) The How-To Geek Guide to Audio Editing: Basic Noise Removal Install a Wii Game Loader for Easy Backups and Fast Load Times The Best of CES (Consumer Electronics Show) in 2011 The Worst of CES (Consumer Electronics Show) in 2011 HTG Projects: How to Create Your Own Custom Papercraft Toy Firefox 4.0 Beta 9 Available for Download – Get Your Copy Now The Frustrations of a Computer Literate Watching a Newbie Use a Computer [Humorous Video] Season0nPass Jailbreaks Current Gen Apple TVs IBM’s Jeopardy Playing Computer Watson Shows The Pros How It’s Done [Video] Tranquil Juice Drop Abstract Wallpaper Pulse Is a Sleek Newsreader for iOS and Android Devices

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