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• How can I be prepared to join a company?

  - by Aerovistae

  There's more to it than that, but this title was the best way I could think of to sum it up. I'm a senior in a good computer science program, and I'm graduating early. About to start interviews and all whatnot. I'm not a super-experienced programmer, not one of those people who started in middle school. I'm decent at this, but I'm not among the best, not nearly. I have to do an awful lot of googling. So today I'm meeting some fellow for lunch at a campus cafe to discuss some front-end details when this tall, good-looking guy begs pardon, says he's new to campus, says he's wondering if we know where he can go to sign up for recruiting developers. Quickly evolves into long conversation: he's the CEO of a seems-to-be-doing-well start-up. Hiring passionate interns and full-times. Sounds great! I take one look at his site on my own computer later, immediately spot a major bug. No idea how to fix it, but I see it. I go over to the page code, and good god. It's the standard amount of code you would expect from a full-scale web application, a couple dozen pages of HTML and scripts. I don't even know where to start reading it. I've built sites from scratch, but obviously never on that scale, nor have I ever worked on one of that scale. I have no idea which bit might generate the bug. But that sets me thinking: How could someone like me possibly settle into an environment like that? A start-up is a very high-pressure working environment. I don't know if I can work at that pace under those constraints-- I would hate to let people down. And with only 10 employees, it's not like anyone has much time to help you get your bearings. Somewhere in there is a question. Can you see it? I'm asking for general advice here. Maybe even anecdotal advice. Is joining a start-up right out of college a scary process? Am I overestimating what it would take to figure out the mass of code behind this site? What's the likelihood a decent but only moderately-experienced coder could earn his pay at such a place? For instance, I know nothing of server-side/back-end programming. Never touched it. That scares me.

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• So, I though I wanted to learn frontend/web development and break out of my comfort zone...

  - by ripper234

  I've been a backend developer for a long time, and I really swim in that field. C++/C#/Java, databases, NoSql, caching - I feel very much at ease around these platforms/concepts. In the past few years, I started to taste end-to-end web programming, and recently I decided to take a job offer in a front end team developing a large, complex product. I wanted to break out of my comfort zone and become more of an "all around developer". Problem is, I'm getting more and more convinced I don't like it. Things I like about backend programming, and missing in frontend stuff: More interesting problems - When I compare designing a server that handle massive data, to adding another form to a page or changing the validation logic, I find the former a lot more interesting. Refactoring refactoring refactoring - I am addicted to Visual Studio with Resharper, or IntelliJ. I feel very comfortable writing code as it goes without investing too much thought, because I know that with a few clicks I can refactor it into beautiful code. To my knowledge, this doesn't exist at all in javascript. Intellisense and navigation - I hate looking at a bunch of JS code without instantly being able to know what it does. In VS/IntelliJ I can summon the documentation, navigate to the code, climb up inheritance hiererchies ... life is sweet. Auto-completion - Just hit Ctrl-Space on an object to see what you can do with it. Easier to test - With almost any backend feature, I can use TDD to capture the requirements, see a bunch of failing tests, then implement, knowing that if the tests pass I did my job well. With frontend, while tests can help a bit, I find that most of the testing is still manual - fire up that browser and verify the site didn't break. I miss that feeling of "A green CI means everything is well with the world." Now, I've only seriously practiced frontend development for about two months now, so this might seem premature ... but I'm getting a nagging feeling that I should abandon this quest and return to my comfort zone, because, well, it's so comfy and fun. Another point worth mentioning in this context is that while I am learning some frontend tools, a lot of what I'm learning is our company's specific infrastructure, which I'm not sure will be very useful later on in my career. Any suggestions or tips? Do you think I should give frontend programming "a proper chance" of at least six to twelve months before calling it quits? Could all my pains be growing pains, and will they magically disappear as I get more experienced? Or is gaining this perspective is valuable enough, even if plan to do more "backend stuff" later on, that it's worth grinding my teeth and continuing with my learning?

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• It's possible to fulfill the social necessity of a human being through a social game in 3D like IMVU?

  - by Totty

  (I'm not advertising nor promoting this game, as it's just an example of my experience and I would like to have your opinion about the matter if possible) I've been started researching "things" about games and I've decided to begin to play IMVU as a friend of mine said it's cool. At first it seemed just another 3d social game, not so cool.. But I've "tried to like" and after 1 day I can say I'm addicted to it! Yes; I will explain better: About the game: You can go in chat-rooms, move to positions. Some positions are like sitting in a sofa, floor, dancing alone or with a partner, kissing and more in this way. In the free version of the game there is no nudity. You can even listen to music, view youtube... The 3d graphics are quite low end, so it's not as real as the paid PC games of today. About my experience: At first I was going with my friend in chat-rooms, they seemed very nice. There were people talking about general stuff, quite like in a real life. Well, I begin to know some girls (yes, virtual girls commanded by a real girl, I hope!). Things happened: Some girls are just crazy, not like in real life, they make out in before even talking; Other girls you can speak a little bit, then they add you to their friend-list. Sometimes they invite to their virtual places. Some girls have really IMVU boyfriends only (but not in reality) and most of them don't even make up in the game, so it's really a level of commitment involved here! But from what my friend told they last for him, at least, about 3 days... Some others have real and IMVU boyfriends that are the same. Until now I haven't find a girl with different boyfriend in the IMVU and reality. Nor multiple boyfriends. There are rooms where the same people find each selves every day and speak about general stuff, relationships and so on... They are nice with you, they "feel" you and show careness. This is what amazes me, they treat you like a real human being and as being their friend in the real world. (of course it's not always like this) There are jealous girls too and competitiveness between females lol, I know you loled! This is kind of social. So today I closed my door in my room and I've played it all day long and guess what, I didn't feel a need to stay with a real person at all. Normally, If I would stay a full day alone I would get quite crazy... So the question is: It's just me that seemed to be able to fulfill my social needs or there is something more? thanks for your precious time for reading my full question,

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• Failed to start up after upgrading software in ubuntu 10.10

  - by Landy

  I asked this question in SuperUser one hour ago, then I know this community so I moved the question here... I've been running Ubuntu 10.10 in a physical x86-64 machine. Today Update Manager reminded me that there are some updates to install and I confirmed the action. I should had read the update list but I didn't. I can only remember there is an update about cups. After the upgrading, Update Manager requires a restart and I confirmed too. But after the restart, the computer can't start up. There are errors in the console. Begin: Running /scripts/init-premount ... done. Begin: Mounting root file system ... Begin: Running /scripts/local-top ... done. [xxx]usb 1-8: new high speed USB device using ehci_hcd and address 3 [xxx]usb 2-1: new full speed USB device using ohci_hcd and address 2 [xxx]hub 2-1:1.0: USB hub found [xxx]hub 2-1:1.0: 4 ports detected [xxx]usb 2-1.1: new low speed USB device using ohci_hcd and address 3 Gave up waiting for root device. Common probles: - Boot args (cat /proc/cmdline) - Check rootdelay=(did the system wait long enough) - Check root= (did the system wait for the right device?) - Missing modules (cat /proc/modules; ls /dev) FATAL: Could not load /lib/modules/2.6.35-22-generic/modules.dep: No such file or directory FATAL: Could not load /lib/modules/2.6.35-22-generic/modules.dep: No such file or directory ALERT! /dev/sda1 does not exist. Dropping to a shell! BusyBox v1.15.3 (Ubuntu 1:1.15.3-1ubuntu5) built-in shell(ash) Enter 'help' for a list of built-in commands. (initramfs)[cursor is here] At the moment, I can't input anything in the console. The keyboard doesn't work at all. What's wrong? How can I check boot args or "root=" as suggested? How can I fix this issue? Thanks. =============== PS1: the /dev/sda1 is type ext4 (rw,nosuid,nodev) PS2: the /dev/sda1 can be mounted and accessed successfully under SUSE 11 SP1 x64. PS3: From this link, I think the keyboard doesn't work because the USB driver is not loaded at that time.

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• Is it OK to repeat code for unit tests?

  - by Pete

  I wrote some sorting algorithms for a class assignment and I also wrote a few tests to make sure the algorithms were implemented correctly. My tests are only like 10 lines long and there are 3 of them but only 1 line changes between the 3 so there is a lot of repeated code. Is it better to refactor this code into another method that is then called from each test? Wouldn't I then need to write another test to test the refactoring? Some of the variables can even be moved up to the class level. Should testing classes and methods follow the same rules as regular classes/methods? Here's an example: [TestMethod] public void MergeSortAssertArrayIsSorted() { int[] a = new int[1000]; Random rand = new Random(DateTime.Now.Millisecond); for(int i = 0; i < a.Length; i++) { a[i] = rand.Next(Int16.MaxValue); } int[] b = new int[1000]; a.CopyTo(b, 0); List<int> temp = b.ToList(); temp.Sort(); b = temp.ToArray(); MergeSort merge = new MergeSort(); merge.mergeSort(a, 0, a.Length - 1); CollectionAssert.AreEqual(a, b); } [TestMethod] public void InsertionSortAssertArrayIsSorted() { int[] a = new int[1000]; Random rand = new Random(DateTime.Now.Millisecond); for (int i = 0; i < a.Length; i++) { a[i] = rand.Next(Int16.MaxValue); } int[] b = new int[1000]; a.CopyTo(b, 0); List<int> temp = b.ToList(); temp.Sort(); b = temp.ToArray(); InsertionSort merge = new InsertionSort(); merge.insertionSort(a); CollectionAssert.AreEqual(a, b); }

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• Software engineering project idea feedback [on hold]

  - by Chris Sewell

  I'm a third year student currently undergoing my project/dissertation section of my degree. I have drafted a proposal for my final year project and would appreciate any feedback. The feedback can be anything constructive either specific to this proposal, the area that I will be working and researching in or my ideas. I will accept all input. Aims My aim is to attempt a proof of concept and prototype a runtime-as-a-service (RaaS). This cloud based runtime will allow clients to dynamically offload tasks or create cloud applications. Currently software-as-a-service (SaaS) cloud applications are purpose built and have a predefined scope in which they can assist or serve the client; this scope cannot be changed without physical alteration to the client and server software. With RaaS the client potentially could define any task it wanted at any time depending on its environment variables, the client and server would then communicate parameters and returns for that task. For the client to utilize a RaaS it must be able to conceive and then define a task using an appropriate XML vocabulary. As the scope of the cloud solution is defined by the client at its runtime, the cloud solution only has to exist for as long as the client requires it to as opposed to a client using a dedicated service. Deliverables The crux of the project will require an XML vocabulary in which the client and server will communicate. I’ll prototype the server application that will dynamically create and manage cloud solutions. The solution will be coded using an interpreted language, such as python or javascript, which can evaluate expressions in runtime or a language that can dynamically compile such as C# or Java. As a further proof of concept I will also produce a mock client that offloads tasks to the server. The report will attempt to explain the different flavours of cloud computing solutions including infrastructure-as-a-service (IaaS), platform-as-a-service (PaaS) and SaaS including real world examples and where the use of a RaaS could have improved the overall example solution. Disclaimer: I'm not requesting stakeholders in my project nor am I delegating work. Any materials other than feedback, advice or directions will not be utilized.

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• Avoiding the Black Hole of Leads

  - by Charles Knapp

  Sales says, "Marketing doesn’t deliver enough qualified leads. So, we generate 90% of our own leads." Meanwhile, Marketing says, "We generate most of the leads. But, Sales doesn’t contact them quickly enough, while the lead is still interested." According to Sirius Decisions: Up to 90% of leads never make it to closure Sales works on only 11% of the leads supplied by Marketing Only 18% of the leads Sales accepts convert to opportunities Yet, 45% of prospects typically buy a product from someone within 12 months The root cause of these commonplace complaints is a disconnect between the funnels of marketing and sales. Unfortunately, we often see companies with an assortment of poorly integrated marketing tools. It takes too long and too many people to move the data around, scrub it, upload it from one system to another, and get it routed to the right sales teams. As a result, leads fall through the cracks, contextual information is lost, and by the time sales actually contacts a customer it may be too late. Sales automation alone is not enough. Marketing automation (including social) is not enough. Sales and Marketing must work together. It’s time to connect the silos of marketing and sales pipelines and analytics. It’s time for integrated Sales and Marketing automation. Integrated pipelines improve lead quality and timeliness. Marketing systems can track a rich set of contextual information about a prospect–self-disclosed information about interests, content viewed, and so on. This insight can equip the sales rep with rich information to make a face-to-face conversation more relevant and more likely to convert to the next stage in the sales process. Integrated lead to revenue (LTR) management provides end-to-end visibility, enabling the company to measure what is working. Marketing can measure its impact on revenue and other business outcomes, and sales can harness and redirect marketing investments to areas where they most help achieve sales objectives. It’s a win-win play. Marketing delivers more leads that are qualified, cuts cost per lead, and demonstrates a strong Return on Marketing Investment (ROMI). Sales spends more time with warm leads and less time on cold calls, achieves higher close rates, and delivers more revenue. Learn more by attending our Integrated Sales and Marketing session at the upcoming CloudWorld conferences. Or, visit our Sales and Marketing Cloud Service site for videos and other learning resources.

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• Switch from back-end to front-end programming: I'm out of my comfort zone, should I switch back?

  - by ripper234

  I've been a backend developer for a long time, and I really swim in that field. C++/C#/Java, databases, NoSql, caching - I feel very much at ease around these platforms/concepts. In the past few years, I started to taste end-to-end web programming, and recently I decided to take a job offer in a front end team developing a large, complex product. I wanted to break out of my comfort zone and become more of an "all around developer". Problem is, I'm getting more and more convinced I don't like it. Things I like about backend programming, and missing in frontend stuff: More interesting problems - When I compare designing a server that handle massive data, to adding another form to a page or changing the validation logic, I find the former a lot more interesting. Refactoring refactoring refactoring - I am addicted to Visual Studio with Resharper, or IntelliJ. I feel very comfortable writing code as it goes without investing too much thought, because I know that with a few clicks I can refactor it into beautiful code. To my knowledge, this doesn't exist at all in javascript. Intellisense and navigation - I hate looking at a bunch of JS code without instantly being able to know what it does. In VS/IntelliJ I can summon the documentation, navigate to the code, climb up inheritance hiererchies ... life is sweet. Auto-completion - Just hit Ctrl-Space on an object to see what you can do with it. Easier to test - With almost any backend feature, I can use TDD to capture the requirements, see a bunch of failing tests, then implement, knowing that if the tests pass I did my job well. With frontend, while tests can help a bit, I find that most of the testing is still manual - fire up that browser and verify the site didn't break. I miss that feeling of "A green CI means everything is well with the world." Now, I've only seriously practiced frontend development for about two months now, so this might seem premature ... but I'm getting a nagging feeling that I should abandon this quest and return to my comfort zone, because, well, it's so comfy and fun. Another point worth mentioning in this context is that while I am learning some frontend tools, a lot of what I'm learning is our company's specific infrastructure, which I'm not sure will be very useful later on in my career. Any suggestions or tips? Do you think I should give frontend programming "a proper chance" of at least six to twelve months before calling it quits? Could all my pains be growing pains, and will they magically disappear as I get more experienced? Or is gaining this perspective is valuable enough, even if plan to do more "backend stuff" later on, that it's worth grinding my teeth and continuing with my learning?

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• Why do I always think I know much less than others? [closed]

  - by John Kenedy

  I have been in programming since primary 6. Since the time DOS comes, I have been doing programming in quickbasic 4.5, then to VB 6, then to C#. In between I also do programming in C++. But every time I open Stack Overflow and trying to help others answering their problems, it seems that I know nothing. I feel that I am so stupid even I have been in programming for so long. I would shock reading all the questions and unable to find any clue. Is technology moving too fast that left out me? I feel that technology changes too fast and I can't keep up, when I know ASP.NET web form, MVC is out, when I know MVC, android/iphone/HTML5 app is popular. It seems that I am chasing something and never reach 'it'. I don't know whether this is correct place for me to talk about this. I just wish to listen to opinion like you, how do you think technology should grow instead of recreating language, adding bug here and there to let programmer figure it out, while big company share the solution among themselves. This is exactly how I feel. The simple example is how do you think why doesn't Dictionary<> in .NET provide iterating the object using index? Why must we use Key or GetEnumerator(). Developer has to google and read wasted hour of hour of time to find pieces of hack code to use reflection to achieve reading from index. Where developer will keep it as collection and valuable code. HOwever when times come, everything changes again, developer has to find answer for new silly problems again! Yes, I really hate it! I hate how many big companies are playing with the developer by cutting a big picture into small puzzle and messing it up and asking developer to place it together themselves. As if they are creating problems for us to solve it, so we are unable to grow upfront, we are being manipulated by those silly problems they have created. Another sample would how difficult to collect Cookies from CookieContainer without passing the URL, yes without the URL and I WANT to get all cookie in the cookiecontainer without knowing the URL, I want to iterate all. Why does micros0ft have to limit me from doing that?

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• No drivers listed?/How to install all drivers? 12.10

  - by madmike59

  So i go to system settings in Ubuntu 12.10 and i want to install my drivers but under the Additional Drivers, My LAN doesnt work, Doesnt even pick up that im plugged in threw Ethernet cord. I have a GTX 670M with 3Gb GDDR5 for a video card and would like to use that. Just need help, pretty new to Ubuntu. Ok when i looked at that other question i did the sudo lspce -nn and this is what i got madmike@Mike-GT70:~$ sudo lspci -nn 00:00.0 Host bridge [0600]: Intel Corporation 3rd Gen Core processor DRAM Controller [8086:0154] (rev 09) 00:01.0 PCI bridge [0604]: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor PCI Express Root Port [8086:0151] (rev 09) 00:02.0 VGA compatible controller [0300]: Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) 00:14.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller [8086:1e31] (rev 04) 00:16.0 Communication controller [0780]: Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 [8086:1e3a] (rev 04) 00:1a.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 [8086:1e2d] (rev 04) 00:1b.0 Audio device [0403]: Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller [8086:1e20] (rev 04) 00:1c.0 PCI bridge [0604]: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 [8086:1e10] (rev c4) 00:1c.2 PCI bridge [0604]: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 3 [8086:1e14] (rev c4) 00:1c.4 PCI bridge [0604]: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 5 [8086:1e18] (rev c4) 00:1d.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 [8086:1e26] (rev 04) 00:1f.0 ISA bridge [0601]: Intel Corporation HM77 Express Chipset LPC Controller [8086:1e57] (rev 04) 00:1f.2 SATA controller [0106]: Intel Corporation 7 Series Chipset Family 6-port SATA Controller [AHCI mode] [8086:1e03] (rev 04) 00:1f.3 SMBus [0c05]: Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller [8086:1e22] (rev 04) 01:00.0 VGA compatible controller [0300]: NVIDIA Corporation Device [10de:1213] (rev ff) 02:00.0 Ethernet controller [0200]: Atheros Communications Inc. Device [1969:e091] (rev 13) 03:00.0 Network controller [0280]: Intel Corporation Centrino Wireless-N 2230 [8086:0887] (rev c4) 04:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5209 PCI Express Card Reader [10ec:5209] (rev 01) 04:00.1 SD Host controller [0805]: Realtek Semiconductor Co., Ltd. RTS5209 PCI Express Card Reader [10ec:5209] (rev 01) Let me know if you need any more info? sorry it took so long.

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• Wireless connection by using command screen

  - by Amadeus

  I installed Ubuntu 12.04 armhf to my beagleboard-xm and now trying to connect to a wireless network. First, I checked if I can search for available networks: ubuntu@arm:~$ iwlist scan lo Interface doesn't support scanning. usb0 Interface doesn't support scanning. wlan0 Scan completed : Cell 01 - Address: EA:7D:EF:60:C9:0B Channel:1 Frequency:2.412 GHz (Channel 1) Quality=70/70 Signal level=-23 dBm Encryption key:on ESSID:"ghostrider" Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s 24 Mb/s; 36 Mb/s; 54 Mb/s Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 48 Mb/s Mode:Ad-Hoc Extra:tsf=000000005a1ab50e Extra: Last beacon: 6242ms ago IE: Unknown: 000A67686F73747269646572 IE: Unknown: 010882848B962430486C IE: Unknown: 030101 IE: Unknown: 06020000 IE: Unknown: 2A0100 IE: Unknown: 2F0100 IE: Unknown: 32040C121860 IE: Unknown: 2D1A2C181BFF00000000000000000000000000000000000000000000 IE: Unknown: 3D16010800000000FF000000000000000000000000000000 IE: Unknown: DD09001018020000000000 Then I edited /etc/network/interfaces file to the following: root@arm:/etc/wpa_supplicant# cat /etc/network/interfaces auto lo iface lo inet loopback # The primary network interface auto eth0 iface eth0 inet dhcp # Example to keep MAC address between reboots #hwaddress ether DE:AD:BE:EF:CA:FE # WiFi Example auto wlan0 iface wlan0 inet dhcp wpa-ssid "ghostrider" wpa-psk "b34d373eb2fb836a43b0afffe783c7d0af694724506c9e77b06d1021302905bf" But I cannot still connect to the wireless network: root@arm:/etc/wpa_supplicant# iwconfig lo no wireless extensions. usb0 no wireless extensions. wlan0 IEEE 802.11bgn ESSID:off/any Mode:Managed Access Point: Not-Asociated Tx-Power=20 dBm Retry long limit:7 RTS thr:off Fragment thr:off Encryption key:off Power Management:on eth0 no wireless extensions. root@arm:/etc/network# ifup wlan0 Failed to bring up wlan0. What is wrong? Should I change any other files also? But I think it was enough. By the way if you are curious about where that wpa-psk came from: zero@ghostrider:~$ wpa_passphrase ghostrider 34bddf67c2 network={ ssid="ghostrider" #psk="34bddf67c2" psk=b34d373eb2fb836a43b0afffe783c7d0af694724506c9e77b06d1021302905bf } I will appreciate any effort to help. Regards, Amadeus ps: Also I tried to connect manually: root@arm:/etc/network# iwconfig wlan0 essid ghostrider key s:34bddf67c2 But this did not solve my problem also.

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• Help writing server script to ban IP's from a list

  - by Chev_603

  I have a VPS that I use as an openvpn and web server. For some reason, my apache log files are filled with thousands of these hack attempts: "POST /xmlrpc.php HTTP/1.0" 404 395 These attack attempts fill up 90% of my logs. I think it's a WordPress vulnerability they're looking for. Obviously they are not successful (I don't even have Wordpress on my server), but it's annoying and probably resource consuming as well. I am trying to write a bash script that will do the following: Search the apache logs and grab the offending IP's (even if they try it once), Sort them into a list with each unique IP on a seperate line, And then block them using the IP table rules. I am a bash newb, and so far my script does everything except Step 3. I can manually block the IP's, but that's tedious and besides, this is Linux and it's perfectly capable of doing it for me. I also want the script to be customizable so that I (or anyone else who wants to use it) can change the variables to suit whatever situation I/they may deal with in the future. Here is the script so far: #!/bin/bash ##IP LIST GENERATOR ##Author Chev Young ##Script to search Apache logs and list IP's based on custom filters ## ##Define our variables: DIRECT=~/Script ##Location of script&where to put results/temp files LOGFILE=/var/log/apache2/access.log ## Logfile to search for offenders TEMPLIST=xml_temp ## Temporary file name IP_LIST=ipstoban ## Name of results file FILTER1=xmlrpc ## What are we looking for? (Requests we want to ban) cd $DIRECT if [ ! -f $TEMPLIST ];then touch $TEMPLIST ##Create temp file fi cat $LOGFILE | grep $FILTER1 >> $DIRECT/$TEMPLIST ## Only interested in the IP's, so: sed -e 's/\([0-9]\+\.[0-9]\+\.[0-9]\+\.[0-9]\+\).*$/\1/' -e t -e d $DIRECT/$TEMPLIST | sort | uniq > $DIRECT/$IP_LIST rm $TEMPLIST ## Clean temp file echo "Done. Results located at $DIRECT/$IP_LIST" So I need help with the next part of the script, which should ban the IP's (incoming and perhaps outgoing too) from the resulting $IP_LIST file. I don't care if it utilizes UFW or IPTables directly, as long as it bans the IP's. I'd probably run it as a cron task. What I'm having trouble with is understanding how to use line of the result file as a seperate variable to do something like: ufw deny $IP1 $IP2 $IP3, ect Any ideas? Thanks.

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• Storing a looong lookup table

  - by inquisitive

  Background The product i am working on has a very long lookup-table. the table contains static data and cannot be auto generated. there are about 500 rows and 10 columns. columns have mostly integers and strings. to complicate the matters, there are actually two such tables. every row in table-1 maps to zero-or-more rows in table-2. we use an SQLite database with two tables. the product installer places the SQLite file in the installation directory. the application is written in dot-net and we use ADO to load the data once on startup. now, the lookup table grows. in each release a month, we add about 10 new entries existing entries are adjusted. every release we fine tune existing entries. The problem a team of (10) developers work on the lookup table. Code goes in the SVN, but the little devil the SQLite does not. this prevents multiple developers to work on it. we do take regular backups of the file, but proper versioning is not possible. we never know who did the breaking change. the worse thing is we dont know if there is any change at all. diff'ing databases is tedious if not impossible. the tables are expected to grow quite large in years to come and we would need developers to work in parallel on it. the data is business critical. we need to be able to audit changes made to it. Question What would be a solution for the problems outlines above? one idea was to transform the whole thing to XML and treat it like just another source file. that way SVN can do the versioning and we can work in parallel. but the data shows relational behavior. with XML we loose the unique and foreign-key constraints. also we cant query it with sql like ease. any help here will be appreciated.

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• Our own Daily WTF

  - by Dennis Vroegop

  Originally posted on: http://geekswithblogs.net/dvroegop/archive/2014/08/20/our-own-daily-wtf.aspxIf you're a developer, you've probably heard of the website the DailyWTF. If you haven't, head on over to http://www.thedailywtf.com and read. And laugh. I'll wait. Read it? Good. If you're a bit like me probably you've been wondering how on earth some people ever get hired as a software engineer. Most of the stories there seem to weird to be true: no developer would write software like that right? And then you run into a little nugget of code one of your co-workers wrote. And then you realize: "Hey, it happens everywhere!" Look at this piece of art I found in our codebase recently: public static decimal ToDecimal(this string input) {     System.Globalization.CultureInfo cultureInfo = System.Globalization.CultureInfo.InstalledUICulture;     var numberFormatInfo = (System.Globalization.NumberFormatInfo)cultureInfo.NumberFormat.Clone();     int dotIndex = input.IndexOf(".");     int commaIndex = input.IndexOf(",");     if (dotIndex > commaIndex)         numberFormatInfo.NumberDecimalSeparator = ".";     else if (commaIndex > dotIndex)         numberFormatInfo.NumberDecimalSeparator = ",";     decimal result;     if (decimal.TryParse(input, System.Globalization.NumberStyles.Float, numberFormatInfo, out result))         return result;     else         throw new Exception(string.Format("Invalid input for decimal parsing: {0}. Decimal separator: {1}.", input, numberFormatInfo.NumberDecimalSeparator)); }  Me and a collegue have been looking long and hard at this and what we concluded was the following: Apparently, we don't trust our users to be able to correctly set the culture in Windows. Users aren't able to determine if they should tell Windows to use a decimal point or a comma to display numbers. So what we've done here is make sure that whatever the user enters, we'll translate that into whatever the user WANTS to enter instead of what he actually did. So if you set your locale to US, since you're a US citizen, but you want to enter the number 12.34 in the Dutch style (because, you know, the Dutch are way cooler with numbers) so you enter 12,34 we will understand this and respect your wishes! Of course, if you change your mind and in the next input field you decide to use the decimal dot again, that's fine with us as well. We will do the hard work. Now, I am all for smart software. Software that can handle all sorts of input the user can think of. But this feels a little uhm, I don't know.. wrong.. Or am I too old fashioned?

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• The Minimalist's Approach to Content Governance

  - by Kellsey Ruppel

  This week on the blog, we want to focus on the content lifecylce and how important it is to have the tools in place to be able to properly manage all te phases of the content lifecylce. John Brunswick has some great advice when it comes to this topic, so expect to hear a lot from him this week! Originally posted by John Brunswick. Let's be honest - content governance is far from an exciting topic. BUT the potential of a very small intranet team creating and maintaining a platform that provides an organization with relevant, high value information, helping workers to get their jobs done with greater accuracy and in less time is exciting. It is easy to quickly start producing content, but the challenge is ensuring that the environment is easy to navigate and use on the third week and during the third year.   What can be done to bridge this gap? Over the next few blog entries let's take a pragmatic, minimalistic view of a process that can help any team manage a wealth of unstructured information. Based on an earlier article that I wrote around Portal Governance, I am going to focus on using technology as much as possible to support the governance of content with minimal involvement from users. The only certainty about content production is that business users are not fans of maintaining content. Maintenance is overhead and is a long-term investment thats value will possibly not be realized under the current content creator's watch. To add context to how we will use technical tools in this process, each post will highlight one section of the content lifecycle process as outlined below Content Lifecycle Stages 1. Request - Understand the education, purpose, resource and success criteria for content 2. Create - Determine access and workflow for content 3. Manage - Understand ownership and review cycles 4. Retire - Act on thresholds established during the request stage Within each state we will also elaborate as to 1. Why - why would we entertain doing this? 2. How - the steps that are needed to make it happen 3. Impact - what is the net benefit or loss based on the process Over the course of this week, we will dive deep into the stages and the minimal amount of time, effort and process within each to make some meaningful gains in the improvement of user experience and productivity in their search for information. It might be a stretch to say that we can make content governance exciting, but hopefully it can end up being painless and paying dividends. And if you'd like to hear first hand from a customer that is managing their content lifecycle with Oracle WebCenter, be sure to join us on Wednesday for this webcast "ResCare Solves Content Lifecycle Challenges with Oracle WebCenter"!

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• No wireless connection using a conceptronic c54i (RT2561/RT61 rev B)

  - by jrosell

  Detected but not working. New install on ubuntu 11.10 using coneptronic C54Ri. As documentation says it uses Ralink drivers.... Any ideas why my wireless does not work? $ lspci -nn | grep -i 'ralink' 01:05.0 Network controller: Ralink corp. RT2561/RT61 rev B 802.11g ifconfig eth0 Link encap:Ethernet HWaddr 00:1e:90:e5:af:13 inet addr:192.168.0.197 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: fe80::21e:90ff:fee5:af13/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:28361 errors:0 dropped:0 overruns:0 frame:0 TX packets:16858 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:39812172 (39.8 MB) TX bytes:1633405 (1.6 MB) Interrupt:43 Base address:0xc000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:80 errors:0 dropped:0 overruns:0 frame:0 TX packets:80 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:6608 (6.6 KB) TX bytes:6608 (6.6 KB) iwconfig wlan0 wlan0 IEEE 802.11abg ESSIDff/any Mode:Managed Access Point: Not-Associated Tx-Power=0 dBm Retry long limit:7 RTS thrff Fragment thrff Power Managementff lsmod | grep rt rt61pci 27493 0 crc_itu_t 12627 1 rt61pci rt2x00pci 14202 1 rt61pci rt2x00lib 48114 2 rt61pci,rt2x00pci mac80211 272785 2 rt2x00pci,rt2x00lib cfg80211 172392 2 rt2x00lib,mac80211 eeprom_93cx6 12653 1 rt61pci parport_pc 32114 1 parport 40930 3 ppdev,parport_pc,lp lsmod | grep rt [ 2497.816989] phy0 -> rt2x00pci_regbusy_read: Error - Indirect register access failed: offset=0x0000308c, value=0xffffffff [ 2497.827112] phy0 -> rt2x00pci_regbusy_read: Error - Indirect register access failed: offset=0x0000308c, value=0xffffffff [ 2497.837430] phy0 -> rt2x00pci_regbusy_read: Error - Indirect register access failed: offset=0x0000308c, value=0xffffffff [ 2497.847528] phy0 -> rt2x00pci_regbusy_read: Error - Indirect register access failed: offset=0x0000308c, value=0xffffffff [ 2497.847632] phy0 -> rt61pci_wait_bbp_ready: Error - BBP register access faile d, aborting. [ 2497.847637] phy0 -> rt61pci_set_device_state: Error - Device failed to enter state 4 (-5). sudo lshw -C network *-network DISABLED description: Wireless interface product: RT2561/RT61 rev B 802.11g vendor: Ralink corp. physical id: 5 bus info: pci@0000:01:05.0 logical name: wlan0 version: 00 serial: fa:b8:14:58:62:35 width: 32 bits clock: 33MHz capabilities: pm cap_list ethernet physical wireless configuration: broadcast=yes driver=rt61pci driverversion=3.0.0-12-generic firmware=0.8 latency=0 link=no multicast=yes wireless=IEEE 802.11abg resources: irq:16 memory:fdef8000-fdefffff iwlist scan lo Interface doesn't support scanning. eth0 Interface doesn't support scanning. wlan0 Failed to read scan data : Network is down uname -mr 3.0.0-12-generic i686 Edit 1 $ rfkill list all 0: phy0: Wireless LAN Soft blocked: no Hard blocked: no On reboot, sudo lshw -C network returns network is ok. Hovever, WPA keeps on asking the wireless key

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• What will be the better way for data retrieval on application that needs to handle limited amount of data.?

  - by Milanix

  This is not really a coding question since, I am not adding any code in here. Since, adding my code snippets itself would make this question really long. Instead, I am pretty interested in knowing a better ways for data retrieval on application that needs to handle limited amount of data which isn't updated regularly. Let's take this example: I am writing an application which gets a schedule as an XML from server. I have written a logic in order to parse XML version and update database only if the version is newer than the local version. Although the update is checked automatically/manually on daily basis based on user preference, the actual version update happens only once per few months or so. Since, this is done by some other authority which doesn't provide API but, rather inform publicly on their changes. The actual XML contains a "(n number of groups)(days in a week) (n number of schedule)" . The group is usually 6 and the number of schedule is usually 2. So basically there would usually be only around 100 strings. Now although I have used SQLite at the moment. I want to know how to make update on database. Should I show progress dialog that the application is updating and exit the app when it's done? Since, my updates are infrequent i don't think this will really harm user experience but, is there any better ways to do it? Because I don't want update to be made when user is searching which is done using database. This will cause an database already open exception. Atleast I have faced this problem before. Is it better to rather parse XML every time when user wants to view certain things or to use SQLite? Since, I make lots of use of adapter in my app to create lists, will that degrade the performance? It would really be a great help if anyone can give me better overview about it. Or may be counter argument against each. Many thanks!

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• Best practice for organizing/storing character/monster data in an RPG?

  - by eclecto

  Synopsis: Attempting to build a cross-platform RPG app in Adobe Flash Builder and am trying to figure out the best class hierarchy and the best way to store the static data used to build each of the individual "hero" and "monster" types. My programming experience, particularly in AS3, is embarrassingly small. My ultra-alpha method is to include a "_class" object in the constructor for each instance. The _class, in turn, is a static Object pulled from a class created specifically for that purpose, so things look something like this: // Character.as package { public class Character extends Sprite { public var _strength:int; // etc. public function Character(_class:Object) { _strength = _class._strength; // etc. } } } // MonsterClasses.as package { public final class MonsterClasses extends Object { public static const Monster1:Object={ _strength:50, // etc. } // etc. } } // Some other class in which characters/monsters are created. // Create a new instance of Character var myMonster = new Character(MonsterClasses.Monster1); Another option I've toyed with is the idea of making each character class/monster type its own subclass of Character, but I'm not sure if it would be efficient or even make sense considering that these classes would only be used to store variables and would add no new methods. On the other hand, it would make creating instances as simple as var myMonster = new Monster1; and potentially cut down on the overhead of having to read a class containing the data for, at a conservative preliminary estimate, over 150 monsters just to fish out the one monster I want (assuming, and I really have no idea, that such a thing might cause any kind of slowdown in execution). But long story short, I want a system that's both efficient at compile time and easy to work with during coding. Should I stick with what I've got or try a different method? As a subquestion, I'm also assuming here that the best way to store data that will be bundled with the final game and not read externally is simply to declare everything in AS3. Seems to me that if I used, say, XML or JSON I'd have to use the associated AS3 classes and methods to pull in the data, parse it, and convert it to AS3 object(s) anyway, so it would be inefficient. Right?

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• In Technology, Ignorance is NOT Bliss

  - by Tanu Sood

  Author: Debra Lilley, ACE Director, UK Proof I’m not technical -  I’ve just finished a Latin America tour with OTN and a funny thing happened that I want to share with you; because it is quite a good analogy for how many of us use technology today and you know how I love analogies. In Costa Rica we had a really long journey up through the mountains to where our conference was to be. The road was windy and narrow and once it got dark there was no scenery to see, boredom set in. At one stage I looked at my watch to see the time, but in the dark I couldn’t make it out, so I thought I would be clever and use the torch in my smartphone! Even though as soon as I switched on the phone it showed the time, I ignored it and used the torch to read my watch. That’s us when we pay maintenance on software, ask for enhancements, and either chose not to upgrade or as I have seen so many times, upgrade but don’t use the new features. I know there are always other factors not least the upgrade costs themselves but in the later releases of all the Oracle family of applications Oracle have done a lot to make the interoperability of them with Oracle Fusion Middleware more successful and in many cases for the first time. My heritage is Oracle E Business Suite (EBS) and the availability of Oracle Weblogic for EBS is fantastic for an Oracle powered organisation that can move away from supporting multiple flavours of application server. The same release made available  - the no downtime patching that Oracle Database 11g introduced with Edition Based Redefinition. I am not saying you must use these features but you must be aware of what each release of your application brings and make a business based decision as to whether it is for you or not. I like to have a simple spreadsheet of features with no-value, nice-to-have, must-have ratings, but make the spreadsheet cumulative so that when you do upgrade you have all the features listed you previously didn’t take up. That way you can avoid the ‘using your phone to read your watch’ scenario. About the Author: Debra Lilley, Fusion Champion, UKOUG Board Member, Fusion User Experience Advocate and ACE Director. Lilley has 18 years experience with Oracle Applications, with E Business Suite since 9.4.1, moving to Business Intelligence Team Lead and Oracle Alliance Director. She has spoken at over 100 conferences worldwide and posts at debrasoraclethoughts  

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• How to write comments to explain the "why" behind the callback function when the function and parameter names are insufficient for that?

  - by snowmantw

  How should I approach writing comments for callback functions? I want to explain the "why" behind the function when the function and parameter names are insufficient to explain what's going on. I have always wonder why comments like this can be so ordinary in documents of libraries in dynamic languages: /** * cb: callback // where's the arguments & effects? */ func foo( cb ) Maybe the common attitude is "you can look into source code on your own after all" which pushes people into leaving minimalist comments like this. But it seems like there should be a better way to comment callback functions. I've tried to comment callbacks in Haskell way: /** * cb: Int -> Char */ func foo(cb) And to be fair, it's usually neat enough. But it gets into trouble when I need to pass some complex structure. The problem being partly due to the lack of type system: /** * cb: Int -> { err: String -> (), success: () -> Char } // too long... */ func foo(cb) Or I have tried this too: /** * cb: Int -> { err: String -> (), * success: () -> Char } // better ? */ func bar(cb) The problem is that you may put the structure in somewhere else, but you must give it a name to reference it. But then when you name a structure you're about to use immediately looks so redundant: // Somewhere else... // ResultCallback: { err: String -> (), success: () -> Char } /** * cb: Int -> ResultCallback // better ?? */ func foo(cb) And it bothers me if I follow the Java-doc like commenting style since it still seems incomplete. The comments don't tell you anything that you couldn't immediately see from looking at the function. /** * @param cb {Function} yeah, it's a function, but you told me nothing about it... * @param err {Function} where should I put this callback's argument ?? * Not to mention the err's own arguments... */ func foo(cb) These examples are JavaScript like with generic functions and parameter names, but I've encountered similar problems in other dynamic languages which allow complex callbacks.

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• Travelling at Magenic

  - by Chris G. Williams

  I occasionally get asked if we travel "a lot" at Magenic. Sometimes the question comes from job candidates. Other times it's clients, recruiters or friends. To give a simple yes or no answer would be a disservice to the person asking the question. So here is my standard answer:It depends.(That was the short version.  Here's the long version...)We do have some guys that are more "national" in focus, and they can travel a fair amount. They also receive a little extra in compensation for doing so. It's a balancing act, and not necessarily a one-size-fits-all situation. Not everyone is well suited to constant travel. Some folks enjoy it and some folks hate it.With our local guys, our general policy is to TRY and keep them close to home whenever possible, but sometimes the needs of the client will dictate otherwise. (As Spock would say... the needs of the many outweigh the needs of the few, or the one.)In most cases though, we really do try to avoid sending our guys on extended travel gigs (i.e. every week for 6 months) when a simple kickoff trip and occasional visit will do. This depends on the nature of the gig, of course. Some types of work lend themselves to this model better than others. Additionally, this can and does vary by office. If one office is having trouble staffing a gig (not enough available bodies) and another office has a few too many folks on the bench, well... you can connect the dots. But again, we try to keep that to a minimum.Lastly, we all have our own thresholds for what we consider "a lot" of travel. There are two parts to this threshold:Half of it is whatever you're accustomed to already. The other half is being honest with yourself about how much you [like/hate] dealing with airports, car rentals, taxis, hotels, disruptions to your workout schedule, time away from friends/family, etc.Knowing a bit about yourself will definitely help you decide how much travel is too much for you.

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• Good, simple reasons for having multiple environments

  - by smp7d

  Throughout my career I had worked at companies that had a collection of different environments for different purposes. We always had more or less our desktop environment, a test environment, a QA environment, a staging environment and a production environment. This went for both servers/applications and any data sources we were using. When I started at my current company I found that 90% of the apps were either developed on a desktop environment against production data sources or developed directly on the production server depending on the platform. I wasn't fazed because I was hired in part to make changes to improve the way the development team functioned, which was clear from my interview process. We slowly started to turn the philosophy and pretty soon, most of the apps could be run in either a desktop, test or production environment. Not too long after that staging came around as well. Now most of our developers see the benefit of this methodology and defend it vigilantly. However, we have a number of legacy apps that never got migrated. We also have a number of legacy programmers who think of this as a waste of time. Unfortunately, we got lip service but never full buy-in from management. We got what we thought was a commitment to invest substantially in this about a year ago, but nothing materialized despite the considerable planning that we put into it. Now we are finding that we need more and more environments. We need help from the server/network administration teams for setup and we need participation from the business stakeholders to support the release cycle. We are at a place now where a project can function what I consider "normally" only if you have the right people on the project and the time to set up the proper environments. I'd love to present a complete argument, but management really has no time and interest in hearing me out until there is a critical issue. I can't really articulate the benefits simply as it always just seemed second nature to me. I was wondering if there are any good, simple, irrefutable reasons for the separation of environments that would get managers with no development experience to get behind this idea. Are there any good resources/literature on the topic?

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• reference list for non-IT driven algorithmic patterns

  - by Quicker

  I am looking for a reference list for non-IT driven algorithmic patterns (which still can be helped with IT implementations of IT). An Example List would be: name; short desc; reference Travelling Salesman; find the shortest possible route on a multiple target path; http://en.wikipedia.org/wiki/Travelling_salesman_problem Ressource Disposition (aka Regulation); Distribute a limited/exceeding input on a given number output receivers based on distribution rules; http://database-programmer.blogspot.de/2010/12/critical-analysis-of-algorithm-sproc.html If there is no such list, but you instantly think of something specific, please 'put it on the desk'. Maybe I can compile something out of the input I get here (actually I am very frustrated as I did not find any such list via research by myself). Details on Scoping: I found it very hard to formulate what I want in a way everything is out that I do not need (which may be the issue why I did not find anything at google). There is a database centric definition for what I am looking for in the section 'Processes' of the second example link. That somehow fits, but the database focus sort of drifts away from the pattern thinking, which I have in mind. So here are my own thoughts around what's in and what's out: I am NOT looking for a foundational algo ref list, which is implemented as basis for any programming language. Eg. the php reference describes substr and strlen. That implements algos, but is not what I am looking for. the problem the algo does address would even exist, if there were no computers (or other IT components) the main focus of the algo is NOT to help other algo's chances are high, that there are implementions of the solution or any workaround without any IT support out there in the world however the algo could be benefitialy implemented/fully supported by a software application = means: the problem of the algo has to be addressed anyway, but running an algo implementation with software automates the process (that is why I posted it on stackoverflow and not somewhere else) typically such algo implementations have more than one input field value and more than one output field value - which implies it could not be implemented as simple function (which is fixed to produce not more than one output value) in a normalized data model often times such algo implementation outputs span accross multiple rows (sometimes multiple tables), whereby the number of output rows depends on the input paraters and rows in the table(s) at start time - which implies that any algo implementation/procedure must interact with a database (read and/or write) I am mainly looking for patterns, not for specific implementations. Example: The Travelling Salesman assumes any coordinates, however it does not say: You need a table targets with fields x and y. - however sometimes descriptions are focussed on examples with specific implementations very much - no worries, as long as the pattern gets clear

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• Understanding When Social Interactions Should Be Resolved in Another Channel

  - by Christina McKeon

  Guest Blogger: Aphrodite Brinsmead, Senior Analyst at Ovum Agents need to respond to customers’ social comments and questions quickly and in the right tone. But more importantly, they need to offer resolutions. Customers care most about how long it takes to find information rather than which channel they are using. They choose to use social media because they are comfortable with the channel and it offers a convenient way to communicate. Ideally agents will resolve questions within social media, but they need guidance as to how and when to escalate interactions to a more private channel. First, businesses should assess the way in which customers are using social media to communicate with them and categorize posts into groups: complaints, feedback, technical queries or more general support questions. They should then consider the types of interactions that can easily be handled within social media and those that need to be followed up in another channel. This will be very dependent on the industry. Examples of queries that can be resolved in social media include Shipping pricing and timeframes Outage updates and resolution plans Flight status information Product stock check Technical support videos or forum posts Availability of facilities Both customers and agents need to be educated about the types of questions they can expect to resolve within social media. As the channel matures as a customer service tool, it needs to have value other than just as a forum for complaints. Social customer service agents need the power to start a web chat or phone call Any questions where customers need to divulge personal details in order to get a resolution will need to be addressed in a private channel: a private social message, web chat, email or phone call. Customers should never disclose their date of birth, social security, credit card number, or healthcare records in a public forum. Flight issues, changes to a booking, billing queries or account updates will all need to be completed via a private interaction. Agents responding to questions on social media need the ability to start a web chat or phone call with the customer. The customer doesn’t want to have to repeat their question and the agent should be empowered to connect customer records and access account or billing information. These agents will need to be trained across different channels and should be able to view all customer communications in one application. They also need to follow up questions that began on a public forum in the initial channel to make it clear that the issue was addressed. In order to make this possible, social media needs to be integrated as part of a broader customer service strategy. Irrespective of how many channels are used to complete an interaction, businesses should prioritize customer satisfaction and issue resolution. They need a clear strategy and trained agents that can handle and respond to social interactions. Follow me on Twitter @diteb. 

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• Java @Contented annotation to help reduce false sharing

  - by Dave

  See this posting by Aleksey Shipilev for details -- @Contended is something we've wanted for a long time. The JVM provides automatic layout and placement of fields. Usually it'll (a) sort fields by descending size to improve footprint, and (b) pack reference fields so the garbage collector can process a contiguous run of reference fields when tracing. @Contended gives the program a way to provide more explicit guidance with respect to concurrency and false sharing. Using this facility we can sequester hot frequently written shared fields away from other mostly read-only or cold fields. The simple rule is that read-sharing is cheap, and write-sharing is very expensive. We can also pack fields together that tend to be written together by the same thread at about the same time. More generally, we're trying to influence relative field placement to minimize coherency misses. Fields that are accessed closely together in time should be placed proximally in space to promote cache locality. That is, temporal locality should condition spatial locality. Fields accessed together in time should be nearby in space. That having been said, we have to be careful to avoid false sharing and excessive invalidation from coherence traffic. As such, we try to cluster or otherwise sequester fields that tend to written at approximately the same time by the same thread onto the same cache line. Note that there's a tension at play: if we try too hard to minimize single-threaded capacity misses then we can end up with excessive coherency misses running in a parallel environment. Theres no single optimal layout for both single-thread and multithreaded environments. And the ideal layout problem itself is NP-hard. Ideally, a JVM would employ hardware monitoring facilities to detect sharing behavior and change the layout on the fly. That's a bit difficult as we don't yet have the right plumbing to provide efficient and expedient information to the JVM. Hint: we need to disintermediate the OS and hypervisor. Another challenge is that raw field offsets are used in the unsafe facility, so we'd need to address that issue, possibly with an extra level of indirection. Finally, I'd like to be able to pack final fields together as well, as those are known to be read-only.

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