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  • Ubuntu 12.04 startup is slow and dmesg output seems to lose several seconds

    - by cdowen
    I use ubuntu on Dell Inspiron n4050.I have upgraded to ubuntu 12.04 from 10.04. But now I find the system startup is a little slow and plymouth only show purple screen without logo during startup. When I use dmesg, it shows such messages: [ 2.497750] EXT4-fs (sda1): mounted filesystem with ordered data mode. Opts: (null) [ 2.603028] usb 2-1.6: new high-speed USB device number 3 using ehci_hcd [ 2.715538] Initializing USB Mass Storage driver... [ 2.715594] usbcore: registered new interface driver usb-storage [ 2.715596] USB Mass Storage support registered. [ 21.317843] Adding 2000892k swap on /dev/sda5. Priority:-1 extents:1 across:2000892k [ 21.323724] ADDRCONF(NETDEV_UP): eth0: link is not ready [ 21.391450] udevd[431]: starting version 175 I wonder what it is doing between 2 second and 21 second. Is it related to being so slow? I tried bootchart. It gave me a complex picture. Sorry I can't post it here. http://3.bp.blogspot.com/-7LX8T5uQvlw/UKhdFMVkp4I/AAAAAAAAADg/dtxePkE94mg/s320/lengzhen-ubuntu-precise-20121118-1.png While ubuntu is booting , I also noticed that it appears:/tmp is not ready or present And sometimes follows *Stop saving kernel messages. Is this the reason dmesg lost output?

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  • Improve efficiency when using parallel to read from compressed stream

    - by Yoga
    Is another question extended from the previous one [1] I have a compressed file and stream them to feed into a python program, e.g. bzcat data.bz2 | parallel --no-notice -j16 --pipe python parse.py > result.txt The parse.py can read from stdin continusuoly and print to stdout My ec2 instance is 16 cores but from the top command it is showing 3 to 4 load average only. From the ps, I am seeing a lot of stuffs like.. sh -c 'dd bs=1 count=1 of=/tmp/7D_YxccfY7.chr 2>/dev/null'; I know I can improve using the -a in.txtto improve performance, but with my case I am streaming from bz2 (I cannot exact it since I don't have enought disk space) How to improve the efficiency for my case? [1] Gnu parallel not utilizing all the CPU

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  • Common Substring of two strings

    - by Chander Shivdasani
    This particular interview-question stumped me: Given two Strings S1 and S2. Find the longest Substring which is a Prefix of S1 and suffix of S2. Through Google, I came across the following solution, but didnt quite understand what it was doing. public String findLongestSubstring(String s1, String s2) { List<Integer> occurs = new ArrayList<>(); for (int i = 0; i < s1.length(); i++) { if (s1.charAt(i) == s2.charAt(s2.length()-1)) { occurs.add(i); } } Collections.reverse(occurs); for(int index : occurs) { boolean equals = true; for(int i = index; i >= 0; i--) { if (s1.charAt(index-i) != s2.charAt(s2.length() - i - 1)) { equals = false; break; } } if(equals) { return s1.substring(0,index+1); } } return null; }

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  • Applescript won't open applications on my external monitor

    - by jpadvo
    I'm trying to open a new MacVim window with Applescript, and have found partial success with this: do shell script "cd \"~/code/application\"; ~/bin/mvim > /dev/null 2>&1" This works fine, and opens a new MacVim window with it's working directory set to ~/code/application. BUT it always opens on the screen of my laptop, not on the external monitor with the currently active space where I am working. Is there a way to get MacVim to open in the current space? Edit: same problem with opening a finder window: tell application "Finder" to make new Finder window

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  • background in JAVA [closed]

    - by leen.zd
    how can i put a background image in my java code? this is my code... what's error? import java.awt.Container; import java.awt.Dimension; import java.awt.Graphics; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import javax.imageio.ImageIO; import javax.swing.JFrame; import javax.swing.JPanel; public class background extends JFrame { private Container c; private JPanel imagePanel; public background() { initialize(); } private void initialize() { setDefaultCloseOperation(EXIT_ON_CLOSE); c = getContentPane(); imagePanel = new JPanel() { public void paint(Graphics g) { try { BufferedImage image = ImageIO.read(new File("http://www.signe-zodiaque.com/images/signes/balance.jpg")); g.drawImage(image, 1000, 2000, null); } catch (IOException e) { e.printStackTrace(); } } }; imagePanel.setPreferredSize(new Dimension(640, 480)); c.add(imagePanel); }

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  • python2.7 help() modules returnd error

    - by GerberaH
    # python Python 2.7.3 (default, Aug 1 2012, 05:14:39) [GCC 4.6.3] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> help() Welcome to Python 2.7! This is the online help utility. If this is your first time using Python, you should definitely check out the tutorial on the Internet at http://docs.python.org/tutorial/. Enter the name of any module, keyword, or topic to get help on writing Python programs and using Python modules. To quit this help utility and return to the interpreter, just type "quit". To get a list of available modules, keywords, or topics, type "modules", "keywords", or "topics". Each module also comes with a one-line summary of what it does; to list the modules whose summaries contain a given word such as "spam", type "modules spam". help> modules Please wait a moment while I gather a list of all available modules... /usr/lib/python2.7/dist-packages/gobject/constants.py:24: Warning: g_boxed_type_register_static: assertion `g_type_from_name (name) == 0' failed import gobject._gobject /usr/lib/python2.7/dist-packages/gtk-2.0/gtk/__init__.py:40: Warning: g_boxed_type_register_static: assertion `g_type_from_name (name) == 0' failed from gtk import _gtk ** (python:6240): CRITICAL **: pyg_register_boxed: assertion `boxed_type != 0' failed /usr/lib/python2.7/dist-packages/gtk-2.0/gtk/__init__.py:40: Warning: cannot register existing type `GdkDevice' from gtk import _gtk /usr/lib/python2.7/dist-packages/gtk-2.0/gtk/__init__.py:40: Warning: g_type_get_qdata: assertion `node != NULL' failed from gtk import _gtk Speicherzugriffsfehler (Speicherabzug geschrieben)

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  • Android Bitmap: Collision Detecting

    - by Aekasitt Guruvanich
    I am writing an Android game right now and I would need some help in the collision of the Pawns on screen. I figured I could run a for loop on the Player class with all Pawn objects on the screen checking whether or not Width*Height intersects with each other, but is there a more efficient way to do this? And if you do it this way, many of the transparent pixel inside the rectangular area will also be considered as collision as well. Is there a way to check for collision between Bitmap on a Canvas that disregard transparent pixels? The class for player is below and the Pawn class uses the same method of display. Class Player { private Resources res; // Used for referencing Bitmap from predefined location private Bounds bounds; // Class that holds the boundary of the screen private Bitmap image; private float x, y; private Matrix position; private int width, height; private float velocity_x, velocity_y; public Player (Resources resources, Bounds boundary) { res = resources; bounds = boundary; image = BitmapFactory.decodeResource(res, R.drawable.player); width = image.getWidth(); height = image.getHeight(); position = new Matrix(); x = bounds.xMax / 2; // Initially puts the Player in the middle of screen y = bounds.yMax / 2; position.preTranslate(x,y); } public void draw(Canvas canvas) { canvas.drawBitmap(image, position, null); } }

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  • Doing "text mode 'splash' game" during boot.

    - by Vi
    Sometimes I want to do something (for example, playing a simple text-mode game) while the system is booting up. This is especially useful when lengthy reiserfs transaction replays are happening. Current hacky way of doing it is: Put the program on initramfs. Before running /sbin/init, "openvt 2 /my/program". Turn off messages from kernel (sysrq 0) Override /dev/console with /dev/null (to prevent boot messages). The problems are: There are STILL some messages interfering with program output. I can't see boot messages by switching to that virtual terminal back. After finishing the boot sequence, /dev/tty2 ends up being attached both to getty and my program. How to do it properly without of running graphical splashes? The system is Linux Debian Squeeze, no dependency based sysv scripts.

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  • Bad previous code. To fix or not to fix?

    - by Viniyo Shouta
    As a freelancer programmer I am often asked to edit part of an application source code in order to add functionalities, fix bugs etc. While I'm on my adventure journey to study the source to do what I'm asked correctly I run into code like: World::User* GetWorld() { map<DWORD,World*>::iterator it = mapWld.find( m_userWorldId ) if( it != mapWld.end() ) return &it->second; return NULL; } if( pUser->GetWorld()->GetId() == 250 ) If I investigate further I end up finding that the DWORD class member of User, userWorldId can be a value non-found in the map mapWld, which will lead to a casuality as also known as crash! The obviously valid way to do it is: World* pWorld = pUser->GetWorld(); if( pWorld && pWorld->GetId() == 250 )//... Sometimes when it's something just 'small' I end up sort of 'fixing' it. But sometimes when I'm on a 500 thousand line source code and this kind of code is everywhere there is no much can do. The question is if it's politically correct to fix some of these things. Think of it; You are not paid to fix it. Perhaps you think it's right, but it was necessarily done that way for some reason and you should not be messing with it. You do not have authorization, you do not own the source and none of the copyrights belong to you. You have authorization to edit issues accordingly to the owners but you're in a hurry, you have many other projects to do, it's the end of the month, you must pay the bills. Sincerely, I think of it as seeing an animal die from a disease in front of you, you have the cure in your hands but you do nothing. What is the best to do in this scenario?

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  • Need help with the naming convention for an incremental variable [closed]

    - by iStryker
    I am using a voting module, that allows you vote either up or down [or reset]. If you vote up, the value is +1. If you vote down, the value is -1. If you vote up then down, the value is -1. I want to extend this module to allow you to vote multiple times, and the votes to be incremental. Examples Up, Up = +1, +1 = +2 Up, Up, Down = +1, +1, -1 = +1 I want to create a new boolean variable. If FALSE/NULL then use the old system +1/-1. If TRUE, voting will be incremental. What should be the name of this variable be? I feel 'incremental' is not the correct name. This module is part of an open-source project and is used on 3,177+ websites, so I want to get the naming convention right. Naturally, I'll be setting an upper and lower limit the variable be. [ie 5 & 0] Side-question: Is there a mathematics term to describe something being either +1/-1?

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  • How can I check for a string match AND an empty file in the same if/then bash script statement?

    - by Mike B
    I'm writing a simple bash script to do the following: 1) Check two files (foo1 and foo2). 2) If foo1 is different from foo2 and foo1 NOT blank, send an email. 3) If foo1 is the same as foo2... or foo1 is blank... do nothing. The blank condition is what's confusing me. Here's what I've got to start with: diff --brief <(sort ./foo1) <(sort ./foo2) >/dev/null comp_value=$? if [ $comp_value -ne 0 ] then mail -s "Alert" [email protected] <./alertfoo fi Obviously this doesn't check for blank contents. Any thoughts on how to do that?

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  • How do I retain previously drawn graphics?

    - by Cromanium
    I've created a simple program that draws lines from a fixed point to a random point each frame. I wanted to keep each line on the screen. However, it always seems to be cleared each time it draws on the spriteBatch even without GraphicsDevice.Clear(color) being called. What seems to be the problem? protected override void Draw(GameTime gameTime) { spriteBatch.Begin(); DrawLine(spriteBatch); spriteBatch.End(); base.Draw(gameTime); } private void DrawLine(SpriteBatch spriteBatch) { Random r = new Random(); Vector2 a = new Vector2(50, 100); Vector2 b = new Vector2(r.Next(0, 640), r.Next(0,480)); Texture2D filler= new Texture2D(GraphicsDevice, 1, 1, false, SurfaceFormat.Color); filler.SetData(new[] { Color.Black }); float length = Vector2.Distance(a, b); float angle = (float)Math.Atan2(b.Y - a.Y, b.X - a.X); spriteBatch.Draw(filler, a, null, Color.Black, angle, Vector2.Zero, new Vector2(length,10.0f), SpriteEffects.None, 0f); } What am I doing wrong?

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  • Dropping multiple objects using an array in Actionscript?

    - by Eratosthenes
    I'm trying to get these fireBalls to drop more often, I'm not sure if I'm using Math.random correctly. Also, for some reason I'm getting a null reference because I think the fireBalls array waits for one to leave the stage before dropping another one? This is the relevant code: var sun:Sun=new Sun var fireBalls:Array=new Array() var left:Boolean; function onEnterFrame(event:Event){ if (left) { sun.x = sun.x - 15; }else{ sun.x = sun.x + 15; } if (fireBalls.length>0&&fireBalls[0].y>stage.stageHeight){ // Fireballs exit stage removeChild(fireBalls[0]); fireBalls.shift(); } for (var j:int=0; j<fireBalls.length; j++){ fireBalls[j].y=fireBalls[j].y+15; if (fireBalls[j].y>stage.stageHeight-fireBall.width/2){ } } if (Math.random()<.2){ // Fireballs shooting from Sun var fireBall:FireBall=new FireBall; fireBall.x=sun.x; addChild(fireBall); fireBalls.push(fireBall); } }

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  • C++ strongly typed typedef

    - by Kian
    I've been trying to think of a way of declaring strongly typed typedefs, to catch a certain class of bugs in the compilation stage. It's often the case that I'll typedef an int into several types of ids, or a vector to position or velocity: typedef int EntityID; typedef int ModelID; typedef Vector3 Position; typedef Vector3 Velocity; This can make the intent of code more clear, but after a long night of coding one might make silly mistakes like comparing different kinds of ids, or adding a position to a velocity perhaps. EntityID eID; ModelID mID; if ( eID == mID ) // <- Compiler sees nothing wrong { /*bug*/ } Position p; Velocity v; Position newP = p + v; // bug, meant p + v*s but compiler sees nothing wrong Unfortunately, suggestions I've found for strongly typed typedefs include using boost, which at least for me isn't a possibility (I do have c++11 at least). So after a bit of thinking, I came upon this idea, and wanted to run it by someone. First, you declare the base type as a template. The template parameter isn't used for anything in the definition, however: template < typename T > class IDType { unsigned int m_id; public: IDType( unsigned int const& i_id ): m_id {i_id} {}; friend bool operator==<T>( IDType<T> const& i_lhs, IDType<T> const& i_rhs ); }; Friend functions actually need to be forward declared before the class definition, which requires a forward declaration of the template class. We then define all the members for the base type, just remembering that it's a template class. Finally, when we want to use it, we typedef it as: class EntityT; typedef IDType<EntityT> EntityID; class ModelT; typedef IDType<ModelT> ModelID; The types are now entirely separate. Functions that take an EntityID will throw a compiler error if you try to feed them a ModelID instead, for example. Aside from having to declare the base types as templates, with the issues that entails, it's also fairly compact. I was hoping anyone had comments or critiques about this idea? One issue that came to mind while writing this, in the case of positions and velocities for example, would be that I can't convert between types as freely as before. Where before multiplying a vector by a scalar would give another vector, so I could do: typedef float Time; typedef Vector3 Position; typedef Vector3 Velocity; Time t = 1.0f; Position p = { 0.0f }; Velocity v = { 1.0f, 0.0f, 0.0f }; Position newP = p + v*t; With my strongly typed typedef I'd have to tell the compiler that multypling a Velocity by a Time results in a Position. class TimeT; typedef Float<TimeT> Time; class PositionT; typedef Vector3<PositionT> Position; class VelocityT; typedef Vector3<VelocityT> Velocity; Time t = 1.0f; Position p = { 0.0f }; Velocity v = { 1.0f, 0.0f, 0.0f }; Position newP = p + v*t; // Compiler error To solve this, I think I'd have to specialize every conversion explicitly, which can be kind of a bother. On the other hand, this limitation can help prevent other kinds of errors (say, multiplying a Velocity by a Distance, perhaps, which wouldn't make sense in this domain). So I'm torn, and wondering if people have any opinions on my original issue, or my approach to solving it.

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  • Convert video from .mp4 to .ogg

    - by Unknown
    I am using ffmpeg version 0.11.1 Copyright (c) 2000-2012 the FFmpeg developers . I need to convert a file .mp4, to .ogg format. I am on Mac OS X, and I have tried this so far: ffmpeg -i sample_mpeg4.mp4 -acodec vorbis -vcodec libtheora -f ogg output.ogv I am getting: Unknown encoder 'libtheora' ffmpeg -i sample_mpeg4.mp4 -acodec libvorbis -vcodec --enable-libtheora output.ogv I am getting: Unknown encoder '--enable-libtheora' ffmpeg -i sample_mpeg4.mp4 -acodec libvorbis -vcodec libtheora -f ogv output.ogv I am getting: [NULL @ 0x7f81bb00f800] Requested output format 'ogv' is not a suitable output format output.ogv: Invalid argument ffmpegtheora is not an option as it can not be install on the server.

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  • What is meant by "no password set" for root account (and otthers)?

    - by MMA
    Several years back, we were more accustomed to changing to the root account using the su command. First, we switched to the root account, and then executed those root commands. Now we are more accustomed to using the sudo command. But we know that the root account is there. We can readily find the home directory of user root. $ ls -ld /root/ drwx------ 18 root root 4096 Oct 22 17:21 /root/ Now my point is, it is stated that "the root password in Ubuntu is left unset". Please see the answers to this question. Most of the answers have something to this effect in the first paragraph. One or two answers further state that "the account is left disabled". Now my (primary) questions are, What is meant by an unset password? Is it blank? Is it null? Or something else more cryptic? How does the account becomes enabled once I set password for it? (sudo password root) In order get a better understanding, I checked the /etc/shadow file. Since I have already set a password for the root account, I can no longer see what is there (encrypted password). So, I created another account and left it disabled. The corresponding entry in the /etc/shadow file is, testpassword:!:16020:0:99999:7::: Now perhaps my above queries need to be changed to, what does an ! in password field mean? Other encrypted passwords are those very long cryptic strings. How come this encrypted form is only one character long? And does an account become disabled if I put an ! in the (encrypted) password field?

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  • Should Starting a Quick Game via Google Game Services be Iterated?

    - by user46727
    I have been following this tutorial for Google Play Game Services. I am a little unclear as to if the room matching algorithm should be looped or not. Can I just initialize this process once and let it time out? Or by iterating through it is it somehow rechecking it? If anyone had the approximate timeout that would be great as well. The problem stems from the fact that even when both phones are signing into the Game Services (at virtually the same time, my friend and I logged in), the room is not registering multiple people. One time my friend's phone even entered the game map, showing that he somehow was able to progress from the room initialization process. Relevant screen update methods which I am starting this matchmaking process: @Override public void update(float deltaTime) { game.options.updateTiles(); if(!isInitiated) { startQuickGame(); } } private void startQuickGame() { // auto-match criteria to invite one random automatch opponent. // You can also specify more opponents (up to 3). if(game.mGoogleClient.isConnected() && !isInitiated) { Bundle am = RoomConfig.createAutoMatchCriteria(1, 3, 0); // build the room config: RoomConfig.Builder roomConfigBuilder = RoomConfig.builder(Network.getInstance()); roomConfigBuilder.setMessageReceivedListener(Network.getInstance()); roomConfigBuilder.setRoomStatusUpdateListener(Network.getInstance()); roomConfigBuilder.setAutoMatchCriteria(am); RoomConfig roomConfig = roomConfigBuilder.build(); // create room: Games.RealTimeMultiplayer.create(game.mGoogleClient, roomConfig); // go to game screen this.mRoom = Network.getInstance().getRoom(); if(this.mRoom != null && this.mRoom.getParticipants().size() >= 2) { game.setScreen(new MultiGameScreen(game, this.mRoom)); isInitiated = true; } } else { game.mGoogleClient.connect(); } }

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  • Setting Environment Variable for Tomcat 6 Servlet

    - by amaevis
    I'm using Ubuntu's default installation of Tomcat 6. I'm deploying a ROOT.war, and trying to set an environment variable specific to it, i.e. accessible from System.getenv() in the Servlet.init(config). According to the docs (http://tomcat.apache.org/tomcat-6.0-doc/config/context.html), I can specify this in a Context element in conf/Catalina/localhost/ROOT.xml. I've created that with these contents: <Context> <Environment name="FOO" value="bar" type="java.lang.String" override="false"/> </Context> And I've deployed the webapp as usual, i.e. to webapps/ROOT.war. Server.getenv("FOO") in the Servlet.init(config) still returns null. What am I missing?

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  • No grub selection after installing kernel Ubuntu 14.04

    - by CPJ
    I have installed a new kernel on my system which can be found by grub but when I restart I can only select the old kernel. Things I tried in other threds with similar problems didn't help. sudo update-grub gives Generating grub configuration file ... Found linux image: /boot/vmlinuz-3.15.0-031500rc2-lowlatency Found initrd image: /boot/initrd.img-3.15.0-031500rc2-lowlatency Found linux image: /boot/vmlinuz-3.15.0-031500rc2-generic Found initrd image: /boot/initrd.img-3.15.0-031500rc2-generic Found linux image: /boot/vmlinuz-3.13.0-24-generic Found initrd image: /boot/initrd.img-3.13.0-24-generic Found memtest86+ image: /boot/memtest86+.elf Found memtest86+ image: /boot/memtest86+.bin done However, afer a reboot I can only choose the 3.13 kernel. Any ideas what happened? I I have a full encrypted hard drive so maybe I have overseen something while installing the new kernel to get this work? The grub config file is GRUB_DEFAULT=0 GRUB_HIDDEN_TIMEOUT_QUIET=false GRUB_TIMEOUT=5 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="" GRUB_ENABLE_CRYPTODISK=1 Any ideas? Thanks.

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  • Selecting objects on a 2D map

    - by Dave
    I have a object selection function by checking the mouse click and getting the relevant object. How ever there is a rare situation where if one object is partially behind the other then both objects are in the given area so im wondering how I can make the game know which one was selected, as currently my method does not know. This is my function that works it out: function getobj(e){ mx = e.pageX - curleft; //mouse click x my = e.pageY - curtop; //mouse click y function searchSprites(sprites, x, y) { var matches = [], i = 0, data = null; for (i = 0; i < spritea.length; ++i) { data = spritea[i].data; if (x > data[0] && y > data[1] && x < data[2] && y < data[3]) { var imageData = ctx2.getImageData(x, y, 1, 1); if(imageData.data[3] !== 0){ return [spritea[i].id]; i = spritea.length; } } } } res = searchSprites(spritea, mx, my); bid = res[0]; if(bid === '1'){ alert('You selected the skyscraper in front!'); }else if(bid === '3'){ alert('You selected the skyscraper behind!'); } } Image of the map: It keeps telling me I clicked the skyscraper behind which is not necessarily what the user is trying to do. How can I improve the accuracy of this ?

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  • Strings are UTF-16&hellip;. There is an error in XML document (1, 1).

    - by Shawn Cicoria
    I had a situation today where an xml document had a directive indicating it was utf-8.  So, the code in question was reading in the “string” of that xml then attempting to de-serialize it using an Xsd generated type. What you end up with is an exception indicating that there’s an error in the Xml document at (1,1) or something to that effect. The fix is, run it through a memory stream – which reads the string, but at utf8 bytes – if you have things that fall outside of 8 bit chars, you’ll get an exception.   //Need to read it to bytes, to undo the fact that strings are UTF-16 all the time. //We want it to handle it as UTF8. byte[] bytes = Encoding.UTF8.GetBytes(_myXmlString); TargetType myInstance = null; using (MemoryStream memStream = new MemoryStream(bytes)) { XmlSerializer tokenSerializer = new XmlSerializer(typeof(TargetType)); myInstance = (TargetType)tokenSerializer.Deserialize(memStream); }   Writing is similar – also, adding the default namespace prevents the additional xmlns additions that aren’t necessary:   XmlWriterSettings settings = new XmlWriterSettings() { Encoding = Encoding.UTF8, Indent = true, NewLineOnAttributes = true, }; XmlSerializerNamespaces xmlnsEmpty = new XmlSerializerNamespaces(); xmlnsEmpty.Add("", "http://www.wow.thisworks.com/2010/05"); MemoryStream memStr = new MemoryStream(); using (XmlWriter writer = XmlTextWriter.Create(memStr, settings)) { XmlSerializer tokenSerializer = new XmlSerializer(typeof(TargetType)); tokenSerializer.Serialize(writer, theInstance, xmlnsEmpty); }

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  • share code between check and process methods

    - by undu
    My job is to refactor an old library for GIS vector data processing. The main class encapsulates a collection of building outlines, and offers different methods for checking data consistency. Those checking functions have an optional parameter that allows to perform some process. For instance: std::vector<Point> checkIntersections(int process_mode = 0); This method tests if some building outlines are intersecting, and return the intersection points. But if you pass a non null argument, the method will modify the outlines to remove the intersection. I think it's pretty bad (at call site, a reader not familiar with the code base will assume that a method called checkSomething only performs a check and doesn't modifiy data) and I want to change this. I also want to avoid code duplication as check and process methods are mostly similar. So I was thinking to something like this: // a private worker std::vector<Point> workerIntersections(int process_mode = 0) { // it's the equivalent of the current checkIntersections, it may perform // a process depending on process_mode } // public interfaces for check and process std::vector<Point> checkIntersections() /* const */ { workerIntersections(0); } std::vector<Point> processIntersections(int process_mode /*I have different process modes*/) { workerIntersections(process_mode); } But that forces me to break const correctness as workerIntersections is a non-const method. How can I separate check and process, avoiding code duplication and keeping const-correctness?

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  • Actionscript - Dropping Multiple Objects Using an Array? [closed]

    - by Eratosthenes
    Possible Duplicate: Actionscript - Dropping Multiple Objects Using an Array? I'm trying to get these fireBalls to drop more often, im not sure if im using Math.random correctly also, for some reason I'm getting a null reference because I think the fireBalls array waits for one to leave the stage before dropping another one? this is the relevant code: var sun:Sun=new Sun var fireBalls:Array=new Array() var left:Boolean; function onEnterFrame(event:Event){ if (left) { sun.x = sun.x - 15; }else{ sun.x = sun.x + 15; } if (fireBalls.length>0&&fireBalls[0].y>stage.stageHeight){ // Fireballs exit stage removeChild(fireBalls[0]); fireBalls.shift(); } for (var j:int=0; j<fireBalls.length; j++){ fireBalls[j].y=fireBalls[j].y+15; if (fireBalls[j].y>stage.stageHeight-fireBall.width/2){ } } if (Math.random()<.2){ // Fireballs shooting from Sun var fireBall:FireBall=new FireBall; fireBall.x=sun.x; addChild(fireBall); fireBalls.push(fireBall); } }

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  • KVM XML config file

    - by awmusic12635
    I have a KVM server that I expanded the LV of then rebooted. However now when booting I get the error: error: Failed to create domain from /home/kvm/kvmx/kvmx.xml error: (domain_definition):1: Document is empty (null) ^ It appears the config file still exits however it is now empty. I attempted to replace the contents of the file with the correct previous information however it continues to wipe it on attempt to boot and fails again with the same error. How would I got about solving this so the file doesn't get wiped on every reboot? OS: Centos 6 64bit I would appreciate any help you may have.

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  • How to post JSON object to a URL without cURL in PHP? [closed]

    - by empyreanphoenix
    I have written a send sms code which uses an available sms api. So, I need to post a string in the json(string in $json) format to a url(url specified in $url var), but I am getting the following error String index out of range: -1 I understand that the error arises when requesting for an index that isn't there, but I dont find how that applies in this case. Please help. Note: name1,name2 and name3 are sender name, phone number and content respectively. Thanks array ( 'method' = 'POST', 'content' = $data, 'header' ="Authentication:$key" . "timeout:50000"."ContentLength: " . strlen ( $data) . "\r\n" ) ); if ($optional_headers != null) { $params ['http'] ['header'] = $optional_headers; } $ctx = stream_context_create ( $params ); try { $fp = fopen ( $url, 'rb', false, $ctx ); $response = stream_get_contents ( $fp ); echo "response"; } catch ( Exception $e ) { echo 'Exception: ' . $e-getMessage (); echo "caught"; } echo "done"; return $response; }

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