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  • Unable to find assembly, C#

    - by PlasmaCube
    So, here's the deal. I've got two ASP.NET applications, both of which use SQLServer Session State management. They also both use the same server. I've got a custom session class in an external DLL, which fully implements serialization, and which both applications have referenced. Each application, in turn, has a class which inherits from the DLL class, and both applications use their own respective classes for their session state. Now, what I was trying to accomplish was that if you wanted to go to the other application, it could look in the session (they all use the same session key) and treat the existing object there as the base (the one from the DLL), extract whatever login info you need, then overwrite the session object with your own. Unfortunately, when the second application attempts to read the session, it seems that it looks for the DLL of the first application, and when it can't find it, it throws an exception. Is there a flaw in my logic? Here's an example: // Global.asax of the 1st app protected void Session_Start(object sender, EventArgs e) { Session.Add( "UserSessionKey", new FirstUserSession()); // FirstUserSession inherits from BaseUserSession } Now the second application: // Global.asax of 2nd app protected void Session_Start(object sender, EventArgs e) { if (Session["UserSessionKey"] != null) { BaseUserSession existing = (BaseUserSession)Session["UserSessionKey"]; SecondUserSession session = new SecondUserSession(); // This also inherits from BaseUserSession session.Authenticated = existing.Authenticated; session.Id = existing.Id; session.Role = existing.Role; Session.Add("UserSessionKey", session); } else { Session.Add("UserSessionKey", new SecondUserSession()); } } Here's the exception stack trace. In this case, "MyCBC" is the real name of the first app, and "ASPTesting" is the second app. [SerializationException: Unable to find assembly 'MyCBC, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.] System.Runtime.Serialization.Formatters.Binary.BinaryAssemblyInfo.GetAssembly() +1871092 System.Runtime.Serialization.Formatters.Binary.ObjectReader.GetType(BinaryAssemblyInfo assemblyInfo, String name) +7545734 System.Runtime.Serialization.Formatters.Binary.ObjectMap..ctor(String objectName, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable) +120 System.Runtime.Serialization.Formatters.Binary.ObjectMap.Create(String name, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable) +52 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryObjectWithMapTyped record) +190 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryHeaderEnum binaryHeaderEnum) +61 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.Run() +253 System.Runtime.Serialization.Formatters.Binary.ObjectReader.Deserialize(HeaderHandler handler, __BinaryParser serParser, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) +168 System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream, HeaderHandler handler, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) +203 System.Web.Util.AltSerialization.ReadValueFromStream(BinaryReader reader) +788 System.Web.SessionState.SessionStateItemCollection.ReadValueFromStreamWithAssert() +55 System.Web.SessionState.SessionStateItemCollection.DeserializeItem(String name, Boolean check) +281 System.Web.SessionState.SessionStateItemCollection.get_Item(String name) +19 System.Web.SessionState.HttpSessionStateContainer.get_Item(String name) +13 System.Web.SessionState.HttpSessionState.get_Item(String name) +13 ASPTesting._Default.Page_Load(Object sender, EventArgs e) in C:\Documents and Settings\sarsstu\My Documents\Projects\Testing\ASPTesting\ASPTesting\Default.aspx.cs:20 System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14 System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35 System.Web.UI.Control.OnLoad(EventArgs e) +99 System.Web.UI.Control.LoadRecursive() +50 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627 Thanks to everyone in advance.

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  • Guilty of unsound programming

    - by TelJanini
    I was reading Robert Rossney's entry on "What's the most unsound program you've had to maintain?" found at: (What's the most unsound program you've had to maintain?) when I realized that I had inadvertently developed a near-identical application! The app consists of an HTTPListener object that grabs incoming POST requests. Based on the information in the header, I pass the body of the request to SQL Server to perform the appropriate transaction. The requests look like: <InvoiceCreate Control="389> <Invoice> <CustomerNumber>5555</CustomerNumber> <Total>300.00</Total> <RushOrder>1</RushOrder> </Invoice> </InvoiceCreate> Once it's received by the HTTPListener object, I perform the required INSERT to the Invoice table using SQL Server's built-in XML handling functionality via a stored procedure: INSERT INTO Invoice (InvoiceNumber, CustomerNumber, Total, RushOrder) SELECT @NEW_INVOICE_NUMBER, @XML.value('(InvoiceCreate/Invoice/CustomerNumber)[1]', 'varchar(10)'), @XML.value('(InvoiceCreate/Invoice/Total)[1]', 'varchar(10)'), @XML.value('(InvoiceCreate/Invoice/Total)[1]', 'varchar(10)') I then use another SELECT statement in the same stored procedure to return the value of the new Invoice Number that was inserted into the Invoices table: SELECT @NEW_INVOICE_NUMBER FOR XML PATH 'InvoiceCreateAck' I then read the generated XML using a SQL data reader object in C# and use it as the response of the HTTPListener object. My issue is, I'm noticing that Robert is indeed correct. All of my application logic exists inside the stored procedure, so I find myself having to do a lot of error-checking (i.e. validating the customer number and invoicenumber values) inside the stored procedure. I'm still a midlevel developer, and as such, am looking to improve. Given the original post, and my current architecture, what could I have done differently to improve the application? Are there any patterns or best practices that I could refer to? What approach would you have taken? I'm open to any and all criticism, as I'd like to do my part to reduce the amount of "unsound programming" in the world.

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  • Converting OpenGL coordinates to lower UIView (and UIImagePickerController)

    - by John Qualis
    I am new to OpenGL on the iPhone. I am developing an iPhone app similar to a barcode reader but with an extra OpenGL layer. The bottommost layer is UIImagePickerController, then I use UIView on top and draw a rectangle at certain coordinates on the iPhone screen. So far everything is OK. Then I am trying to draw an OpenGL 3-D model in that rectangle. I am able to load a 3-D model in the iPhone based on this code here - http://iphonedevelopment.blogspot.com/2008/12/start-of-wavefront-obj-file-loader.html I am not able to transform the coordinates of the rectangle into OpenGL coordinates. Appreciate any help. Do I need to use a matrix to translate the currentPosition of the 3-D model so it is drawn within myRect? The code is given below. -(void)setupView:(GLView*)view { const GLfloat zNear = 0.01, zFar = 1000.0, fieldOfView = 45.0; GLfloat size; glEnable(GL_DEPTH_TEST); glMatrixMode(GL_PROJECTION); size = zNear * tanf(DEGREES_TO_RADIANS(fieldOfView) / 2.0); CGRect rect = view.bounds; glFrustumf(-size, size, -size / (rect.size.width / rect.size.height), size / (rect.size.width / rect.size.height), zNear, zFar); glViewport(0, 0, rect.size.width, rect.size.height); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glClearColor(0.0f, 0.0f, 0.0f, 0.0f); NSString *path = [[NSBundle mainBundle] pathForResource:@"plane" ofType:@"obj"]; OpenGLWaveFrontObject *theObject = [[OpenGLWaveFrontObject alloc] initWithPath:path]; Vertex3D position; position.z = -8.0; position.y = 3.0; position.x = 2.0; theObject.currentPosition = position; self.plane = theObject; [theObject release]; } - (void)drawView:(GLView*)view; { static GLfloat rotation = 0.0; glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); glColor4f(0.0, 0.5, 1.0, 1.0); // the coordinates of the rectangle are // myRect.x, myRect.y, myRect.width, myRect.height // Do I need to use a matrix to translate the currentPosition of the // 3-D model so it is drawn within myRect? //glOrthof(-160.0f, 160.0f, -240.0f, 240.0f, -1.0f, 1.0f); [plane drawSelf]; }

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  • IO::Pipe - close(<handle>) does not set $?

    - by danboo
    My understanding is that closing the handle for an IO::Pipe object should be done with the method ($fh->close) and not the built-in (close($fh)). The other day I goofed and used the built-in out of habit on a IO::Pipe object that was opened to a command that I expected to fail. I was surprised when $? was zero, and my error checking wasn't triggered. I realized my mistake. If I use the built-in, IO:Pipe can't perform the waitpid() and can't set $?. But what I was surprised by was that perl seemed to still close the pipe without setting $? via the core. I worked up a little test script to show what I mean: use 5.012; use warnings; use IO::Pipe; say 'init pipes:'; pipes(); my $fh = IO::Pipe->reader(q(false)); say 'post open pipes:'; pipes(); say 'return: ' . $fh->close; #say 'return: ' . close($fh); say 'status: ' . $?; say q(); say 'post close pipes:'; pipes(); sub pipes { for my $fd ( glob("/proc/self/fd/*") ) { say readlink($fd) if -p $fd; } say q(); } When using the method it shows the pipe being gone after the close and $? is set as I expected: init pipes: post open pipes: pipe:[992006] return: 1 status: 256 post close pipes: And, when using the built-in it also appears to close the pipe, but does not set $?: init pipes: post open pipes: pipe:[952618] return: 1 status: 0 post close pipes: It seems odd to me that the built-in results in the pipe closure, but doesn't set $?. Can anyone help explain the discrepancy? Thanks!

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  • How do I install PyYAML into local install of Python?

    - by Daryl Spitzer
    I've installed Python 2.6.4 into (a subdirectory in) my home directory on a Linux machine with Python 2.3.4 pre-installed, because I need to run some code that I've decided would require too much work to make it run on 2.3.4. (I'm not on the sudoers list for that machine.) I was hoping I could run ~/Python-2.6.4/python setup.py install (from the PyYAML directory in my home directory, where I untarred the PyYAML sources) and it would be smart enough to install it into my local Python 2.6.4 install. But it's not. (See the P.S.) Is it possible to install PyYAML into my local Python install, so that "import yaml" will work when I invoke that Python? If so, how do I do that? P.S. Here's the output when I ran ~/Python-2.6.4/python setup.py install: running install running build running build_py creating build/lib.linux-ppc64-2.6 creating build/lib.linux-ppc64-2.6/yaml copying lib/yaml/composer.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/nodes.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/dumper.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/resolver.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/events.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/emitter.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/error.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/loader.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/cyaml.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/scanner.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/__init__.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/serializer.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/reader.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/representer.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/constructor.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/tokens.py -> build/lib.linux-ppc64-2.6/yaml copying lib/yaml/parser.py -> build/lib.linux-ppc64-2.6/yaml running build_ext creating build/temp.linux-ppc64-2.6 checking if libyaml is compilable gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -I/home/dspitzer/Python-2.6.4/Include -I/home/dspitzer/Python-2.6.4 -c build/temp.linux-ppc64-2.6/check_libyaml.c -o build/temp.linux-ppc64-2.6/check_libyaml.o build/temp.linux-ppc64-2.6/check_libyaml.c:2:18: yaml.h: No such file or directory build/temp.linux-ppc64-2.6/check_libyaml.c: In function `main': build/temp.linux-ppc64-2.6/check_libyaml.c:5: error: `yaml_parser_t' undeclared (first use in this function) build/temp.linux-ppc64-2.6/check_libyaml.c:5: error: (Each undeclared identifier is reported only once build/temp.linux-ppc64-2.6/check_libyaml.c:5: error: for each function it appears in.) build/temp.linux-ppc64-2.6/check_libyaml.c:5: error: syntax error before "parser" build/temp.linux-ppc64-2.6/check_libyaml.c:6: error: `yaml_emitter_t' undeclared (first use in this function) build/temp.linux-ppc64-2.6/check_libyaml.c:8: warning: implicit declaration of function `yaml_parser_initialize' build/temp.linux-ppc64-2.6/check_libyaml.c:8: error: `parser' undeclared (first use in this function) build/temp.linux-ppc64-2.6/check_libyaml.c:9: warning: implicit declaration of function `yaml_parser_delete' build/temp.linux-ppc64-2.6/check_libyaml.c:11: warning: implicit declaration of function `yaml_emitter_initialize' build/temp.linux-ppc64-2.6/check_libyaml.c:11: error: `emitter' undeclared (first use in this function) build/temp.linux-ppc64-2.6/check_libyaml.c:12: warning: implicit declaration of function `yaml_emitter_delete' libyaml is not found or a compiler error: forcing --without-libyaml (if libyaml is installed correctly, you may need to specify the option --include-dirs or uncomment and modify the parameter include_dirs in setup.cfg) running install_lib creating /usr/local/lib/python2.6 error: could not create '/usr/local/lib/python2.6': Permission denied

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  • Useful software for netbook?

    - by Moayad Mardini
    I'm looking for recommendations of good software that are particularly useful for netbooks. Software that run great on small screens and low CPU/RAM requirments. I'll start off with the following : Operating Systems: Ubuntu Netbook Remix. Easy Peasy: A fork of Ubuntu Netbook Remix that was once called UBuntu EEE. It isn't just for eeePCs though. Definitely worth a look if vanilla Netbook Remix isn't cutting it. (MarkM) Damn Small Linux (Source) Windows 7: With trimming the installation or compressing the Windows directory to fit on an 8GB SSD. (Will Eddins) nLite: A utility to install a lightweight version of Windows XP without the unnecessary components (like Media Player, Internet Explorer, Outlook Express, MSN Explorer, Messenger...). Utilites: TouchFreeze: To disable the touch pad while typing (Source) InSSIDer: Not only does it make it easier to find and keep a wireless connection, but it turns a netbook into the perfect mobile tool for troubleshooting wireless networks. (phenry) AltMove: Adds more functionality to your mouse for interacting with windows. (Rob) ASUS Font Resizer Utility and other tools by ASUS, specific to ASUS Eee PC series. Internet: Run FileZilla FTP client for a small screen : You can hide a lot of FileZilla's interface parts in the View menu, even the directory trees. Go into Settings = Interface and move the message log next to the transfer queue, if you haven't hidden them both or you want to see them. Select a theme with 16x16 icons. (Source) IDEs and Text Editors: Best lightweight IDE/Text Editor: A question on Stack Overflow that has many good suggestions of IDEs and general text editors for programmers. What’s a good linux C/C++ IDE for a low-res screen?: IDEs for Linux-powered netbooks. Online tools: Dropbox: Since the Netbook has limited disk space, you would like to use Cloud Apps like Dropbox and Ubuntu One so that you don't run out of space especially if you are on a holiday. Later when you go back to your desktop with big hard disk,you can take out the files from your dropbox repo. (Manish Sinha) Google products: like Docs, Calendar and Reader (aviraldg) Web sites and software lists: Netbookfiles.com: Netbook specific software downloads. Software Apps to Maximise your Netbook Battery Power: Netbooks are known for their portability. Not only are they small and lightweight but with their increased power efficiency, batteries can last much longer than conventional laptops. This also means you no longer have to carry a power adapter with you! Several brands emphasis the longevity of the battery as a strong selling point, and for those people who travel a lot, it sure is. Free Must-Have Netbook Apps: Finding software for netbooks can present challenges due to limited hard drive space, processor power, RAM, and screen real-estate. That doesn't mean you have to do without essential programs. The apps below cover all the bases -- entertainment, productivity, security, and communication -- without compromising on performance or usability. Best of all, they're free! Useful Netbook Software: With short battery lives and small resolution screens Netbooks, unlike many other computers on the market, could so with some specific software for their use. Now, not all of those I’ve found are specifically designed for Netbooks, but all are relevant. And they’re designed for Windows XP. The question is community wiki, so feel free to edit it. Updated, thank you all for suggestions.

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  • VMWare Network bug in multiple VMWare Workstation versions if using a hardcoded IP address

    - by onyxruby
    I'm having a very tricky problem with some of my VM sessions being unable to reach the Internet or even ping the gateway. I have just set up a new VM Workstation (7) on a W2K8 64bit server (I'll be converting to ESXI 4 once I can find a decent book on it, so for the meanwhile I use workstation). I have imported a number of VM's and setup some new ones on the server.In short the problem with some of the VM's being unable to reach the Internet is that they can't reach the gateway. I've looking at a number of things and can pretty safely rule out the following: Switch, Router, DHCP Server, DNS, Client IP configuration, Routes and typos. The problem is that some of the new clients cannot reach the gateway if their IP address is hardcoded, they can't even ping it by IP address. That rules out DNS and DHCP. Now, if I allow them to get their IP address by DHCP they can reach the gateway and Internet without issue. The interesting thing on this, is that this behavior occurs even if I leave the DNS information hardcoded under TCP/IP settings. It doesn't work unless the IP and gateway are handed out by DHCP even though the same information IP info is being used by the host. Fundamentally from the standpoint of the clients, they are trying to reach the exact same gateway using the exact same IP information regardless of whether they are hardcoded or assigned by DHCP. Here's an example of one client. IP Address 192.168.7.66 - Subnet Mask 255.255.255.0 - Gateway 192.168.7.254 - DNS1 192.168.7.44 - DNS2 192.168.7.254. The issue occurs across six different microsoft operating systems, Windows 7 and Windows 2008 variants all have the issue. My W2K3, XP, Vista and W98 clients all work without issue with hardcoded IP addresses. I have tried things like rearranging the DNS order, flushing DNS and so on. It's not a routing or switch issue as the clients can work just fine if they get their IP by DHCP. It's not a paramater issue as the exact same paramaters are handed out by DHCP as I plug in by hand. It's not a DNS issue as clients cant reach other clients even with IP addresses only. I have run a tracert to the gateway by IP address and it times out on the very first hop before failing on hop3 with destination host unreachable. If I get the IP address by DHCP the tracert finds the gateway (and Internet) without issue. I have read a few other posts online in forums talking about this problem randomly occuring over the years in other VM versions as well, so I suspect some kind of long standing bug. Does anyone have any ideas on this? Is it possibly a bug with Windows 7 and W2K clients under VM?

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  • Active Directory Time Synchronisation - Time-Service Event ID 50

    - by George
    I have an Active Directory domain with two DCs. The first DC in the forest/domain is Server 2012, the second is 2008 R2. The first DC holds the PDC Emulator role. I sporadically receive a warning from the Time-Service source, event ID 50: The time service detected a time difference of greater than %1 milliseconds for %2 seconds. The time difference might be caused by synchronization with low-accuracy time sources or by suboptimal network conditions. The time service is no longer synchronized and cannot provide the time to other clients or update the system clock. When a valid time stamp is received from a time service provider, the time service will correct itself. Time sync in the domain is configured with the second DC to synchronise using the /syncfromflags:DOMHIER flag. The first DC is configured to sync time using a /syncfromflags:MANUAL /reliable:YES, from a peerlist consisting of a number of UK based stratum 2 servers, such as ntp2d.mcc.ac.uk. I'm confused why I receive this event warning. It implies that my PDC emulator cannot synchronise time with a supposedly reliable external time source, and it quotes a time difference of 5 seconds for 900 seconds. It's worth also mentioning that I used to use a UK pool from ntp.org but I would receive the warning much more often. Since updating to a number of UK based academic time servers, it seems to be more reliable. Can someone with more experience shed some light on this - perhaps it is purely transient? Should I disregard the warning? Is my configuration sound? EDIT: I should add that the DCs are virtual, and installed on two separate VMware ESXi/vSphere physical hosts. I can also confirm that as per MDMarra's comment and best practice, VMware timesync is disabled, since: c:\Program Files\VMware\VMware Tools\VMwareToolboxCmd.exe timesync status returns Disabled. EDIT 2 Some strange new issue has cropped up. I've noticed a pattern. Originally, the event ID 50 warnings would occur at about 1230pm each day. This is interesting since our veeam backup happens at 12 midday. Since I made the changes discussed here, I now receive an event ID 51 instead of 50. The new warning says that: The time sample received from peer server.ac.uk differs from the local time by -40 seconds (Or approximately 40 seconds). This has happened two days in a row. Now I'm even more confused. Obviously the time never updates until I manually intervene. The issue seems to be related to virtualisation and veeam. Something may be occuring when veeam is backing up the PDCe. Any suggestions? UPDATE & SUMMARY msemack's excellent list of resources below (the accepted answer) provided enough information to correctly configure the time service in the domain. This should be the first port of call for any future people looking to verify their configuration. The final "40 second jump" issue I have resolved (there are no more warnings) through adjusting the VMware time sync settings as noted in the veeam knowledge base article here: http://www.veeam.com/kb1202 In any case, should any future reader use ESXi, veeam or not, the resources here are an excellent source of information on the time sync topic and msemack's answer is particularly invaluable.

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  • Unable to connect to SVN server on VPS : Subversion Configuration Problem

    - by Pritam Barhate
    Hello everybody, I purchased a VPS account (centos-5-x86_64) from Hostgator mainly for the purpose of setting up an online Subversion Server. This is the first time I am managing a VPS and my linux skills are not so great, but I have basic knowledge of the OS and have been using it on and off as desktop from last few years. So after foxing through a few tutorials online, as the first step I logged in using SSH root account provided by Hostgator and tried to run, yum install mod_dav_svn subversion As it turns out my account has Cpanel/WHM and since it some concept of easy apache straight forward procedure of yum install mod_dav_svn subversion won't work. After that I found out how it can be worked out by compiling the source and stuff. But the whole procedure looked long and scary. [I am just a linux nub]. so I decided I would just skip whole apache integration stuff and just access the server using svn:// protocol, anyways that's how I configure svn on our LAN. So I installed subversion using yum install subversion It installed fine. Then I created a folder /svn_repos/testproject and ran svnadmin create /svn_repos/testproject/ No Problems Using vi I changed svnserve.conf and passwd files for the repository and added a user with my name. Anonymous users don't have any access, authenticated users have write access. Then I started svnserve using svnserve -d then in same terminal window svn list svn://localhost/svn_repos/testproject Asks for authentication for realm, provided root password then for svn username and password. Provided both. The command returns nothing but exists properly. Returns nothing is understood I didn't import anything. But if try to access svn remotely using in another terminal: svn list svn://ip.add.of.server/svn_repos/testproject svn: Can't connect to host 'ip.add.of.server': Operation timed out Is what I get. Parallels Power Panel that I got from Hostgator reports that: The firewall is not active now. To activate the firewall, choose one of the firewall operation modes. So if firewall is not running and I can access svn using localhost, why the operation is timing out when I try to access svn from a remote machine? Experienced network admins please help. Thanks in advance. Also please suggest a good book which gives detailed information on configuring Dedicated servers + WHM and CPanel.

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  • Establishing a web page bookmarking process - looking for ideas to improve

    - by Matt
    Like many others, I have a process for bookmarking web pages to read later. My requirements for web page bookmarking are: Ability to bookmark pages must be available from all (within reason) platforms - PC/browser, mobile device, etc. Bookmarks must be centrally stored (implicit from #2) so that I can read the bookmarks from anywhere/any device Full text of web pages must be stored Bonus features would be: Bookmarks and page content should be full text searchable Maintain an archive indefinitely Distinguish between what's read vs. unread Bookmarked page content is cleaned up, e.g. ads eliminated, unnecessary html removed, pages better formatted for reading My current process (which addresses most of these requirements) is as follows: I set up a Gmail account with 2 labels, "Bookmarks Unread" and "Bookmarks Read" Gmail filters set up such that depending on the form of the address (using Gmail's '+string' functionality in addresses), the incoming bookmark gets labeled appropriately On each of my browsers/devices, I have an address book entry for [email protected] and [email protected]. If I want to clean up the page content, I use the Readability bookmarklet which does a great job of giving me the essential content only Anywhere I have Firefox, I use the Send Page by Email extension which, with 2 clicks, allows me to send the cleaned-up Readability page URL and content to one of the above email addresses. Where I don't have Firefox (e.g. iPhone or other mobile device) I use the native ability to send the current link via email (most/all apps have them, including the browser, RSS readers, NYTimes, etc.). In most cases (unless it's built into the particular app), this won't include the page body. The process is almost perfect. I've got the central access and ubiquitous access of Gmail as the storage mechanism, full text searchability (due to Gmail, but of course only for the URLs I send from that Firefox extension), a cleaned up page due to Readability, ability to read offline (assuming I use an IMAP client against Gmail) and permanent archiving of content, including what's been read vs. unread. The missing pieces are: The Send Page by Email Firefox extension seems to only send X bytes of a web page. Or some portion. So it limits my full text searchability. Where I don't have Firefox, I can only send the link, so no full text search at all in those cases. Instapaper looks like it meets most of my requirements (and bonus items). The only downside to me (personal preference) is that central storage is based on Instapaper vs. something more broad like Gmail, which as a generalized service and with Google behind it pretty much means it's permanent. I'm not too hung up on this, but I would definitely prefer to keep Gmail if possible. An upside of Instapaper is that it does the page clean-up as well as stores the entire page content, unlike my Firefox extension. Thoughts on addressing the gaps and improving this process further?

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  • Reinstall Postfix

    - by Kevin
    I tried to reinstall Postfix, but I get this bunch of errors: root@***:/etc/init.d# sudo apt-get install -f postfix Reading package lists... Done Building dependency tree Reading state information... Done Suggested packages: procmail postfix-mysql postfix-pgsql postfix-ldap postfix-pcre resolvconf postfix-cdb mail-reader The following NEW packages will be installed: postfix 0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded. Need to get 0B/1,389kB of archives. After this operation, 3,531kB of additional disk space will be used. Preconfiguring packages ... Selecting previously deselected package postfix. (Reading database ... 56122 files and directories currently installed.) Unpacking postfix (from .../postfix_2.7.1-1ubuntu0.1_amd64.deb) ... Processing triggers for ureadahead ... Processing triggers for ufw ... Processing triggers for man-db ... Setting up postfix (2.7.1-1ubuntu0.1) ... Configuration file `/etc/init.d/postfix' ==> File on system created by you or by a script. ==> File also in package provided by package maintainer. What would you like to do about it ? Your options are: Y or I : install the package maintainer's version N or O : keep your currently-installed version D : show the differences between the versions Z : start a shell to examine the situation The default action is to keep your current version. *** postfix (Y/I/N/O/D/Z) [default=N] ? Y Installing new version of config file /etc/init.d/postfix ... Adding group `postfix' (GID 109) ... Done. Adding system user `postfix' (UID 106) ... Adding new user `postfix' (UID 106) with group `postfix' ... Not creating home directory `/var/spool/postfix'. Creating /etc/postfix/dynamicmaps.cf Adding tcp map entry to /etc/postfix/dynamicmaps.cf Adding group `postdrop' (GID 115) ... Done. setting myhostname: ***.net setting alias maps setting alias database setting myorigin setting destinations: ***.net, localhost.***.net, , localhost setting relayhost: setting mynetworks: 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 setting mailbox_size_limit: 0 setting recipient_delimiter: + setting inet_interfaces: all Postfix is now set up with a default configuration. If you need to make changes, edit /etc/postfix/main.cf (and others) as needed. To view Postfix configuration values, see postconf(1). After modifying main.cf, be sure to run '/etc/init.d/postfix reload'. Running newaliases postalias: fatal: /etc/mailname: cannot open file: Permission denied dpkg: error processing postfix (--configure): subprocess installed post-installation script returned error exit status 1 Processing triggers for libc-bin ... ldconfig deferred processing now taking place Errors were encountered while processing: postfix E: Sub-process /usr/bin/dpkg returned an error code (1) I tried aptitude purge, remove, autoclean and all of dpkg options (configure, remove, purge) but nothing did the trick. /etc/mailname exists (0644 root:root) with as content *.net (fetched from hostname). What am I doing wrong?

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  • Start a software company offshore

    - by Mascarpone
    Hello Everybody, I own a small, very young, EU based (Italy) company, and among other things, we sell IT solutions. I have a degree in applied mathematics, and I mainly deal with user interfaces, embedded systems, automation and web applications. You can say that I'm an enlightened entrepreneur because I work only with open source software (OS, IDE, I release under BSD , ... everything is free as in freedom), I give high importance to post sales services and customer satisfaction, plus I think I'm the best boss someone could desire (LOL), as I have google in mind when I think about IT workers rights. But the most beautiful thing is that, although everybody advised us not to use open source, is that we are quite profitable!!! (for the sixth trimester in a row). Now I offshore most of the work to an Indian company. I divide the work in modules and I outsource the longer or more trivial ones. I spend a lot of time defining the specifications and I leave the hard work to them. Using productivity bonuses, a lot of prototypes and third-party audits I think that my software has reached a very good quality level. I would like to start my own software development company, in order to improve control over process and cut costs. Obviously I can't afford the cost of labor in the EU, so I thought about opening a company in Asia. What I need Is: 1) Cheap labor - I can afford to give productivity bonuses and higher than average wages and stay profitable just because labor is cheap. 2) Many talents - I need a good level of tertiary education, and a good number of graduates, so I can hire junior developers and train and teach them according to my needs and philosophies (e.g.: open source mind) 3) Good infrastructure - buildings, transport, internet, .... everything that a company might need. I thought about 3 possible candidates: 1) India - I already work with indian people, I know that they are realiable and speak a good english. Big cities are too expensive, but maybe a small city like lucknow http://en.wikipedia.org/wiki/Lucknow could suits my needs. 2) China - They say it's cheaper than India, but I everytime I worked with a chineese company the language was a big barrier. They work hard, are somewhat skilled and cheap but maybe it's a risky path. Plus I feel a little uncofortable with their lack of human rights. 3) Philippines - Same as china: cheaper than india, but maybe less educated. Where do you think it's the best place to start a software company? Any reading or book to advise? thank you very much

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  • Rebasing a branch which is public

    - by Dror
    I'm failing to understand how to use git-rebase, and I consider the following example. Let's start a repository in ~/tmp/repo: $ git init Then add a file foo $ echo "hello world" > foo which is then added and committed: $ git add foo $ git commit -m "Added foo" Next, I started a remote repository. In ~/tmp/bare.git I ran $ git init --bare In order to link repo to bare.git I ran $ git remote add origin ../bare.git/ $ git push --set-upstream origin master Next, lets branch, add a file and set an upstream for the new branch b1: $ git checkout -b b1 $ echo "bar" > foo2 $ git add foo2 $ git commit -m "add foo2 in b1" $ git push --set-upstream origin b1 Now it is time to switch back to master and change something there: $ echo "change foo" > foo $ git commit -a -m "changed foo in master" $ git push At this point in master the file foo contain changed foo, while in b1 it is still hello world. Finally, I want to sync b1 with the progress made in master. $ git checkout b1 $ git fetch origin $ git rebase origin/master At this point git st returns: # On branch b1 # Your branch and 'origin/b1' have diverged, # and have 2 and 1 different commit each, respectively. # (use "git pull" to merge the remote branch into yours) # nothing to commit, working directory clean At this point the content of foo in the branch b1 is change foo as well. So what does this warning mean? I expected I should do a git push, git suggests to do git pull... According to this answer, this is more or less it, and in his comment @FrerichRaabe explicitly say that I don't need to do a pull. What's going on here? What is the danger, how should one proceed? How should the history be kept consistent? What is the interplay between the case described above and the following citation: Do not rebase commits that you have pushed to a public repository. taken from pro git book. I guess it is somehow related, and if not I would love to know why. What's the relation between the above scenario and the procedure I described in this post.

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  • Lighttpd with FastCGI configuration running ViewVC - rewrite problems

    - by 0xC0000022L
    At the moment I am struggling with the configuration of lighttpd together with ViewVC. The configuration was ported from Apache 2.2.x, which is still running on the machine, serving the WebDAV/SVN stuff, being proxied through. Now, the problem I am having appears to be with the rewrite rules and I'm not really sure what I am missing here. Here's my configuration (slightly condensed to keep it concise): var.hgwebfcgi = "/var/www/vcs/bin/hgweb.fcgi" var.viewvcfcgi = "/var/www/vcs/bin/wsgi/viewvc.fcgi" var.viewvcstatic = "/var/www/vcs/templates/docroot" var.vcs_errorlog = "/var/log/lighttpd/error.log" var.vcs_accesslog = "/var/log/lighttpd/access.log" $HTTP["host"] =~ "domain.tld" { $SERVER["socket"] == ":443" { protocol = "https://" ssl.engine = "enable" ssl.pemfile = "/etc/lighttpd/ssl/..." ssl.ca-file = "/etc/lighttpd/ssl/..." ssl.use-sslv2 = "disable" setenv.add-environment = ( "HTTPS" => "on" ) url.rewrite-once += ("^/mercurial$" => "/mercurial/" ) url.rewrite-once += ("^/$" => "/viewvc.fcgi" ) alias.url += ( "/viewvc-static" => var.viewvcstatic ) alias.url += ( "/robots.txt" => var.robots ) alias.url += ( "/favicon.ico" => var.favicon ) alias.url += ( "/mercurial" => var.hgwebfcgi ) alias.url += ( "/viewvc.fcgi" => var.viewvcfcgi ) $HTTP["url"] =~ "^/mercurial" { fastcgi.server += ( ".fcgi" => ( ( "bin-path" => var.hgwebfcgi, "socket" => "/tmp/hgwebdir.sock", "min-procs" => 1, "max-procs" => 5 ) ) ) } else $HTTP["url"] =~ "^/viewvc\.fcgi" { fastcgi.server += ( ".fcgi" => ( ( "bin-path" => var.viewvcfcgi, "socket" => "/tmp/viewvc.sock", "min-procs" => 1, "max-procs" => 5 ) ) ) } expire.url = ( "/viewvc-static" => "access plus 60 days" ) server.errorlog = var.vcs_errorlog accesslog.filename = var.vcs_accesslog } } Now, when I access the domain.tld, I correctly see the index of the repositories. However, when I look at the links for each respective repository (or click them, for that matter), it's of the form https://domain.tld/viewvc.fcgi/reponame instead of the intended https://domain.tld/reponame. What do I have to change/add to achieve this? Do I have to "abuse" the index file mechanism somehow? Goal is to keep the /mercurial alias functional. So far I've tried sifting through the lighttpd book from Packt again, also through the lighttpd documentation, but found nothing that seemed to match the problem.

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  • Excel 2010: dynamic update of drop down list based upon datasource validation worksheet changes

    - by hornetbzz
    I have one worksheet for setting up the data sources of multiple data validation lists. in other words, I'm using this worksheet to provide drop down lists to multiple other worksheets. I need to dynamically update all worksheets upon any of a single or several changes on the data source worksheet. I may understand this should come with event macro over the entire workbook. My question is how to achieve this keeping the "OFFSET" formula across the whole workbook ? Thx To support my question, I put the piece of code that I'm trying to get it working : Provided the following informations : I'm using such a formula for a pseudo dynamic update of the drop down lists, for example : =OFFSET(MyDataSourceSheet!$O$2;0;0;COUNTA(MyDataSourceSheet!O:O)-1) I looked into the pearson book event chapter but I'm too noob for this. I understand this macro and implemented it successfully as a test with the drop down list on the same worksheet as the data source. My point is that I don't know how to deploy this over a complete workbook. Macro related to the datasource worksheet : Option Explicit Private Sub Worksheet_Change(ByVal Target As Range) ' Macro to update all worksheets with drop down list referenced upon ' this data source worksheet, base on ref names Dim cell As Range Dim isect As Range Dim vOldValue As Variant, vNewValue As Variant Dim dvLists(1 To 6) As String 'data validation area Dim OneValidationListName As Variant dvLists(1) = "mylist1" dvLists(2) = "mylist2" dvLists(3) = "mylist3" dvLists(4) = "mylist4" dvLists(5) = "mylist5" dvLists(6) = "mylist6" On Error GoTo errorHandler For Each OneValidationListName In dvLists 'Set isect = Application.Intersect(Target, ThisWorkbook.Names("STEP").RefersToRange) Set isect = Application.Intersect(Target, ThisWorkbook.Names(OneValidationListName).RefersToRange) ' If a change occured in the source data sheet If Not isect Is Nothing Then ' Prevent infinite loops Application.EnableEvents = False ' Get previous value of this cell With Target vNewValue = .Value Application.Undo vOldValue = .Value .Value = vNewValue End With ' LOCAL dropdown lists : For every cell with validation For Each cell In Me.UsedRange.SpecialCells(xlCellTypeAllValidation) With cell ' If it has list validation AND the validation formula matches AND the value is the old value If .Validation.Type = 3 And .Validation.Formula1 = "=" & OneValidationListName And .Value = vOldValue Then ' Debug ' MsgBox "Address: " & Target.Address ' Change the cell value cell.Value = vNewValue End If End With Next cell ' Call to other worksheets update macros Call Sheets(5).UpdateDropDownList(vOldValue, vNewValue) ' GoTo NowGetOut Application.EnableEvents = True End If Next OneValidationListName NowGetOut: Application.EnableEvents = True Exit Sub errorHandler: MsgBox "Err " & Err.Number & " : " & Err.Description Resume NowGetOut End Sub Macro UpdateDropDownList related to the destination worksheet : Sub UpdateDropDownList(Optional vOldValue As Variant, Optional vNewValue As Variant) ' Debug MsgBox "Received info for update : " & vNewValue ' For every cell with validation For Each cell In Me.UsedRange.SpecialCells(xlCellTypeAllValidation) With cell ' If it has list validation AND the validation formula matches AND the value is the old value ' If .Validation.Type = 3 And .Value = vOldValue Then If .Validation.Type = 3 And .Value = vOldValue Then ' Change the cell value cell.Value = vNewValue End If End With Next cell End Sub

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  • SQL Server Log File Won't Shrink due cause "log are pending replication" on non replicated DB?

    - by user796466
    I have a non Mission Critial DB 9am-5pm SQL Server database that I have set up to do nightly full backups and log backups every 30 minutes during business hours. The database is in full recovery and normally I have no reason to truncate/shrink logs unless I do some heavy maintenance. Log backups manage the size with no issue. However I have not been at this client for several weeks and upon inspection I noticed that the log had grown to about 10 times the size of the .mdf file. I poked around backups had been running and I had not gotten any severity error alerts (SQL mail). I attempted to put DB in simple recovery and shrink the log, this was no good. I precede to try a log backup and I got: The log was not truncated because records at the beginning of the log are pending replication or Change Data Capture. Ensure the Log Reader Agent or capture job is running or use sp_repldone to mark transactions as distributed or captured. Restart SQL Server rinse repeat same thing ... I said ??? Replication is not nor ever has been set up on this DB or database /server ??? So the log backups have not been flushing the .ldf. So I did a couple hours of research and I found: http://www.sqlmonster.com/Uwe/Forum.aspx/sql-server/5445/Log-file-is-not-truncated-inspite-of-regular-log-backup http://www.eggheadcafe.com/software/aspnet/30708322/the-log-was-not-truncated-because-records-at-the-beginning-of-the-log-are-pending-replication.aspx seems to be some kind of poorly documented bug ?? The solution seems to have been to run exec sp_repldone, more precisley EXEC sp_repldone @xactid = NULL, @xact_segno = NULL, @numtrans = 0, @time= 0, @reset = 1 This procedure can be used in emergency situations to allow truncation of the transaction log when transactions pending replication are present. Using this procedure prevents Microsoft SQL Server 2000 from replicating the database until the database is unpublished and republished. ~ MSDN When I do that I get the following Msg 18757, Level 16, State 1, Procedure sp_repldone, Line 1 Unable to execute procedure. The database is not published. Execute the procedure in a database that is published for replication. Which makes sense Because the DB has never been published for replication. I have several questions: A) First and foremost is, WTF is going on ? What is causeing this, I am interested in knowing the why here ? Is this genuinley a bug or is there some aspect of the backup that is not functioning properly that cause's the DB to mimick a replicated state ? Someone please edify me on this. B) Second ... Do I really have to publish / replicate this DB to exec this SP to fix this ??? Sounds crazy or is there some T-SQL that I can put it in a published state exec the proc and be on my way ... C) Third, if I do indeed have to publish this database to exec the SP to release this unneeded mis replicated/intended log , to get my .ldf file and backup back on track. How do I publish the database without an online host that it is asking for ??? I don't generally do this kind of database administration and need some guidance. Sorry if this is too verbose but just voicing the question helps me clarify it ... Thank you in advance for your help

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  • Recovering damaged external hard disk by installing internally

    - by nfarshchi
    I had a 1TB Western Digital (My book series) 3.5" USB3. One day, the SATA to USB3 converter board was damaged and has not worked since. I decided to open the cover and use the HDD as an internal HDD. When I attached the HDD to my PC and booted up in Windows, it asked me which type of ????? I want to use "MBR or GBR" (I dont remember the exact question) I chose MBR and Windows gave me a 1TB empty Hard drive. I tried to recover with recover my files and some other recovery programs but no success. Some one told me that you should choosed GBR instead of MBR . How can I do that now? Another guy told me that the SATA to USB3 converter board is coded to save data on HDD and you can not use them internally without losing data, and I should find another SATA to USB3 board (exact same). It is impossible to find because they are not produced any more. Please help me to find a solution to bring back my data. UPDATE I have 1TB WD "Mybook" USB 3. the board that convert sata to usb3 was damaged. so when the HDD was in the box computer did not recognize it. I opened the box and remove HDD to use it internal. after connecting to my PC windows showed me one massage that I had two choice MBR or GPT I choosed MBR one and windows gave me 1TB empty new volume. I tried many recovery software to recover my data but no success. I brought it to one expert recovery company and they told me the converter board (SATA to USB3) make some encryption on data and with out that board you cannot recover any thing. so I bought another empty WD box and put the HDD inside but even after that also there is no file. I tried to recover again in this state but no success. so I have some unanswered question. does this converted boards make any password or encryption? if yes how can I solve it? does using many recovery programs affected my data? any suggestion or solution for bring back my data? I had use recovery programs such as : recover my files , EaseUS data recovery, easy recovery, test disk, Ontrack easy recovery . Note: when I was using test disk it asked me to choose which partition table I want to use. as it was I choose NTFS, does this made any change on data?

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  • bluetooth connection using pybluez

    - by srj0408
    I am working on bluetooth not exactly on bluetooth stack-development but to use bluetooth in one of my project. I had done all that before using some of the py-bluez commands like hciconfig, hcitool scan , then simple-agents and using serial module inside python. But that was quite random. We were able to connect only one specific device based on its bluetooth address and there was no facility of reconnection once the devices are disconnected. Now i want to try out this stuff in a sequential manner like this (i am doing that all on a RPI and for at present on ubuntu 12.04.) i) Store some names in a file along with some other information with respect to that device. ii) Run a script to find out the device in locality with those names and if any one if found, report that. For this step, i had taken a reference from BTBook , made available from MIT. Below is the script for the same, but that script only search for the single name. from bluetooth import * target_name = "XT1033" target_address = None nearby_devices = discover_devices() for address in nearby_devices: if target_name == lookup_name( address ): target_address = address break if target_address is not None: print "found target bluetooth device with address ", target_address connect_socket(target_address); else: print "could not find target bluetooth device nearby" iii) Connect the device using client sock. But i dont have any device on which i can write a simple python script. My client can be any device that will be publishing data. Now i came through a script in the same book, that actually connect to a client requesting permission to connect to server. from bluetooth import * port = 1 server_sock=BluetoothSocket( RFCOMM ) server_sock.bind(("",port)) server_sock.listen(1) client_sock, client_info = server_sock.accept() print "Accepted connection from ", client_info data = client_sock.recv(1024) print "received [%s]" % data client_sock.close() server_sock.close() here client_sock, client_info = server_sock.accept() provide the client address and port requested to be connected. Can i pass address obtained from the earlier script to this, so that it connect server to the client? iv) Then if client get disconnected, re-connect(a simple polling can be used.) All this stuff can be done using bash and py-bluez functions but i want to do that in a sequential manner.I am not a master in python but i can do some small stuff. Can any one guide me for the same or can direct me to more usefull resource through which i can continue my coding part after finding the "X", "Y" named devices.

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  • SQL SERVER – Beginning SQL Server: One Step at a Time – SQL Server Magazine

    - by pinaldave
    I am glad to announce that along with SQLAuthority.com, I will be blogging on the prominent site of SQL Server Magazine. My very first blog post there is already live; read here: Beginning SQL Server: One Step at a Time. My association with SQL Server Magazine has been quite long, I have written nearly 7 to 8 SQL Server articles for the print magazine and it has been a great experience. I used to stay in the United States at that time. I moved back to India for good, and during this process, I had put everything on hold for a while. Just like many things, “temporary” things become “permanent” – coming back to SQLMag was on hold for long time. Well, this New Year, things have changed – once again, I am back with my online presence at SQLMag.com. Everybody is a beginner at every task or activity at some point of his/her life: spelling words for the first time; learning how to drive for the first time, etc. No one is perfect at the start of any task, but every human is different. As time passes, we all develop our interests and begin to study our subject of interest. Most of us dream to get a job in the area of our study – however things change as time passes. I recently read somewhere online (I could not find the link again while writing this one) that all the successful people in various areas have never studied in the area in which they are successful. After going through a formal learning process of what we love, we refuse to stop learning, and we finally stop changing career and focus areas. We move, we dare and we progress. IT field is similar to our life. New IT professionals come to this field every day. There are two types of beginners – a) those who are associated with IT field but not familiar with other technologies, and b) those who are absolutely new to the IT field. Learning a new technology is always exciting and overwhelming for enthusiasts. I am working with database (in particular) for SQL Server for more than 7 years but I am still overwhelmed with so many things to learn. I continue to learn and I do not think that I should ever stop doing so. Just like everybody, I want to be in the race and get ahead in learning the technology. For the same, I am always looking for good guidance. I always try to find a good article, blog or book chapter, which can teach me what I really want to learn at this stage in my career and can be immensely helpful. Quite often, I prefer to read the material where the author does not judge me or assume my understanding. I like to read new concepts like a child, who takes his/her first steps of learning without any prior knowledge. Keeping my personal philosophy and preference in mind, I will be blogging on SQL Server Magazine site. I will be blogging on the beginners stuff. I will be blogging for them, who really want to start and make a mark in this area. I will be blogging for all those who have an extreme passion for learning. I am happy that this is a good start for this year. One of my resolutions is to help every beginner. It is totally possible that in future they all will grow and find the same article quite ‘easy‘ – well when that happens, it indicates the success of the article and material! Well, I encourage everybody to read my SQL Server Magazine blog – I will be blogging there frequently on various topics. To begin, we will be talking about performance tuning, and I assure that I will not shy away from other multiple areas. Read my SQL Server Magazine Blog: Beginning SQL Server: One Step at a Time I think the title says it all. Do leave your comments and feedback to indicate your preference of subject and interest. I am going to continue writing on subject, and the aim is of course to help grow in this field. Reference : Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Optimization, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority News, T SQL, Technology

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  • Using Unity – Part 1

    - by nmarun
    I have been going through implementing some IoC pattern using Unity and so I decided to share my learnings (I know that’s not an English word, but you get the point). Ok, so I have an ASP.net project named ProductWeb and a class library called ProductModel. In the model library, I have a class called Product: 1: public class Product 2: { 3: public string Name { get; set; } 4: public string Description { get; set; } 5:  6: public Product() 7: { 8: Name = "iPad"; 9: Description = "Not just a reader!"; 10: } 11:  12: public string WriteProductDetails() 13: { 14: return string.Format("Name: {0} Description: {1}", Name, Description); 15: } 16: } In the Page_Load event of the default.aspx, I’ll need something like: 1: Product product = new Product(); 2: productDetailsLabel.Text = product.WriteProductDetails(); Now, let’s go ‘Unity’fy this application. I assume you have all the bits for the pattern. If not, get it from here. I found this schematic representation of Unity pattern from the above link. This image might not make much sense to you now, but as we proceed, things will get better. The first step to implement the Inversion of Control pattern is to create interfaces that your types will implement. An IProduct interface is added to the ProductModel project. 1: public interface IProduct 2: { 3: string WriteProductDetails(); 4: } Let’s make our Product class to implement the IProduct interface. The application will compile and run as before despite the changes made. Add the following references to your web project: Microsoft.Practices.Unity Microsoft.Practices.Unity.Configuration Microsoft.Practices.Unity.StaticFactory Microsoft.Practices.ObjectBuilder2 We need to add a few lines to the web.config file. The line below tells what version of Unity pattern we’ll be using. 1: <configSections> 2: <section name="unity" type="Microsoft.Practices.Unity.Configuration.UnityConfigurationSection, Microsoft.Practices.Unity.Configuration, Version=1.2.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/> 3: </configSections> Add another block with the same name as the section name declared above – ‘unity’. 1: <unity> 2: <typeAliases> 3: <!--Custom object types--> 4: <typeAlias alias="IProduct" type="ProductModel.IProduct, ProductModel"/> 5: <typeAlias alias="Product" type="ProductModel.Product, ProductModel"/> 6: </typeAliases> 7: <containers> 8: <container name="unityContainer"> 9: <types> 10: <type type="IProduct" mapTo="Product"/> 11: </types> 12: </container> 13: </containers> 14: </unity> From the Unity Configuration schematic shown above, you see that the ‘unity’ block has a ‘typeAliases’ and a ‘containers’ segment. The typeAlias element gives a ‘short-name’ for a type. This ‘short-name’ can be used to point to this type any where in the configuration file (web.config in our case, but all this information could be coming from an external xml file as well). The container element holds all the mapping information. This container is referenced through its name attribute in the code and you can have multiple of these container elements in the containers segment. The ‘type’ element in line 10 basically says: ‘When Unity requests to resolve the alias IProduct, return an instance of whatever the short-name of Product points to’. This is the most basic piece of Unity pattern and all of this is accomplished purely through configuration. So, in future you have a change in your model, all you need to do is - implement IProduct on the new model class and - either add a typeAlias for the new type and point the mapTo attribute to the new alias declared - or modify the mapTo attribute of the type element to point to the new alias (as the case may be). Now for the calling code. It’s a good idea to store your unity container details in the Application cache, as this is rarely bound to change and also adds for better performance. The Global.asax.cs file comes for our rescue: 1: protected void Application_Start(object sender, EventArgs e) 2: { 3: // create and populate a new Unity container from configuration 4: IUnityContainer unityContainer = new UnityContainer(); 5: UnityConfigurationSection section = (UnityConfigurationSection)ConfigurationManager.GetSection("unity"); 6: section.Containers["unityContainer"].Configure(unityContainer); 7: Application["UnityContainer"] = unityContainer; 8: } 9:  10: protected void Application_End(object sender, EventArgs e) 11: { 12: Application["UnityContainer"] = null; 13: } All this says is: create an instance of UnityContainer() and read the ‘unity’ section from the configSections segment of the web.config file. Then get the container named ‘unityContainer’ and store it in the Application cache. In my code-behind file, I’ll make use of this UnityContainer to create an instance of the Product type. 1: public partial class _Default : Page 2: { 3: private IUnityContainer unityContainer; 4: protected void Page_Load(object sender, EventArgs e) 5: { 6: unityContainer = Application["UnityContainer"] as IUnityContainer; 7: if (unityContainer == null) 8: { 9: productDetailsLabel.Text = "ERROR: Unity Container not populated in Global.asax.<p />"; 10: } 11: else 12: { 13: IProduct productInstance = unityContainer.Resolve<IProduct>(); 14: productDetailsLabel.Text = productInstance.WriteProductDetails(); 15: } 16: } 17: } Looking the ‘else’ block, I’m asking the unityContainer object to resolve the IProduct type. All this does, is to look at the matching type in the container, read its mapTo attribute value, get the full name from the alias and create an instance of the Product class. Fabulous!! I’ll go more in detail in the next blog. The code for this blog can be found here.

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  • Ask How-To Geek: Learning the Office Ribbon, Booting to USB with an Old BIOS, and Snapping Windows

    - by Jason Fitzpatrick
    You’ve got questions and we’ve got answers. Today we highlight how to master the new Office interface, USB boot a computer with outdated BIOS, and snap windows to preset locations. Learning the New Office Ribbon Dear How-To Geek, I feel silly asking this (in light of how long the new Office interface has been out) but my company finally got around to upgrading from Windows XP and Office 2000 so the new interface it totally new to me. Can you recommend any resources for quickly learning the Office ribbon and the new changes? I feel completely lost after two decades of the old Office interface. Help! Sincerely, Where the Hell is Everything? Dear Where the Hell, We think most people were with you at some point in the last few years. “Where the hell is…” could possibly be the slogan for the new ribbon interface. You could browse through some of the dry tutorials online or even get a weighty book on the topic but the best way to learn something new is to get hands on. Ribbon Hero turns learning the new Office features and ribbon layout into a game. It’s no vigorous round of Team Fortress mind you, but it’s significantly more fun than reading a training document. Check out how to install and configure Ribbon Hero here. You’ll be teaching your coworkers new tricks in no time. Boot via USB with an Old BIOS Dear How-To Geek, I’m trying to repurpose some old computers by updating them with lightweight Linux distros but the BIOS on most of the machines is ancient and creaky. How ancient? It doesn’t even support booting from a USB device! I have a large flash drive that I’ve turned into a master installation tool for jobs like this but I can’t use it. The computers in question have USB ports; they just aren’t recognized during the boot process. What can I do? USB Bootin’ in Boise Dear USB Bootin’, It’s great you’re working to breathe life into old hardware! You’ve run into one of the limitations of older BIOSes, USB was around but nobody was thinking about booting off of it. Fortunately if you have a computer old enough to have that kind of BIOS it’s likely to also has a floppy drive or a CDROM drive. While you could make a bootable CDROM for your application we understand that you want to keep using the master USB installer you’ve made. In light of that we recommend PLoP Boot Manager. Think of it like a boot manager for your boot manager. Using it you can create a bootable floppy or CDROM that will enable USB booting of your master USB drive. Make a CD and a floppy version and you’ll have everything in your toolkit you need for future computer refurbishing projects. Read up on creating bootable media with PLoP Boot Manager here. Snapping Windows to Preset Coordinates Dear How-To Geek, Once upon a time I had a company laptop that came with a little utility that snapped windows to preset areas of the screen. This was long before the snap-to-side features in Windows 7. You could essentially configure your screen into a grid pattern of your choosing and then windows would neatly snap into those grids. I have no idea what it was called or if was anymore than a gimmick from the computer manufacturer, but I’d really like to have it on my new computer! Bend and Snap in San Francisco, Dear Bend and Snap, If we had to guess, we’d guess your company must have had a set of laptops from Acer as the program you’re describing sounds exactly like Acer GridVista. Fortunately for you the application was extremely popular and Acer released it independently of their hardware. If, by chance, you’ve since upgraded to a multiple monitor setup the app even supports multiple monitors—many of the configurations are handy for arranging IM windows and other auxiliary communication tools. Check out our guide to installing and configuring Acer GridVista here for more information. Have a question you want to put before the How-To Geek staff? Shoot us an email at [email protected] and then keep an eye out for a solution in the Ask How-To Geek column. Latest Features How-To Geek ETC How to Upgrade Windows 7 Easily (And Understand Whether You Should) The How-To Geek Guide to Audio Editing: Basic Noise Removal Install a Wii Game Loader for Easy Backups and Fast Load Times The Best of CES (Consumer Electronics Show) in 2011 The Worst of CES (Consumer Electronics Show) in 2011 HTG Projects: How to Create Your Own Custom Papercraft Toy Download the New Year in Japan Windows 7 Theme from Microsoft Once More Unto the Breach – Facebook Apps Can Now Access Your Address and Phone Number Dial Zero Speeds You Through Annoying Customer Service Menus Complete Dropquest 2011 and Receive Free Dropbox Storage Desktop Computer versus Laptop Wallpaper The Kids Have No Idea What Old Tech Is [Video]

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  • Getting Started with Boxee

    - by DigitalGeekery
    Boxee is a free Media PC application that runs on Windows, Mac, and Ubuntu Linux. With Boxee, you can integrate online video, music and pictures, with your own local media and social networking. Today we are going to take a closer look at Boxee and some of it’s features. Note: We used Windows 7 for this tutorial. Your experience on a Mac or Ubuntu Linux build may vary slightly. Hardware Requirements x86 (Intel/AMD processor) based system running at 1.0GHz or greater 512MB system memory (RAM) or more Video card capable of OpenGL 1.4, Direct X 9.0 Software Requirements Mac OS X 10.4+ (Intel based processor) Ubuntu Linux 9.04+ x86 only Windows XP / Vista / 7 (64 bit in Vista or 7) Installing Boxee Before downloading and installing Boxee, you’ll need to register for a free account. (See link below) Once your account is registered and verified, you’ll be able to log in and download the application. Installation is pretty straightforward…just take the defaults. Boxee will open in full screen mode and you’ll be prompted to login with your username and password. Before you login, you may want to take a moment to click on the “Guide” icon and learn a bit about navigating in Boxee. Some basic keyboard navigation is as follows. Move right, left, up, & down with the arrow keys. Hit “Enter” to make a selection, the forward slash key “\” to toggle between full screen and windowed mode, and “Esc” to go back to the previous screen. For Playback, the volume is controlled by plus & minus (+/-) keys, you can Play / Pause using the spacebar, and skip using the arrow keys. Boxee will also work with any infrared remote. If you have an iPhone or iPod Touch you can download software to enable them as a Boxee remote. If you’re using a mouse and keyboard, hover over the username and password boxes to enter your login credentials. If using a a remote, click your OK button and enter credentials with the on screen keyboard. Click “Done” when finished.   When you are ready to login, enter your credentials and click “Login.” On first login, you’ll be prompted to calibrate your screen. If you choose “Skip” you can always calibrate your screen later under Settings > Appearance > Screen. When Boxee opens, you’ll be greeted by the Home screen. To the left will be your Feeds. This will be any recommended content from friends on Boxee, and social networks such as Facebook and Twitter. Although, when you first login, it will mainly be info from the Boxee staff. You’ll have “Featured” content in the center and your Queue on the right. You’ll also have the Menu along the top.   Pop Up Menu The Pop Menu can be accessed by hitting the “Esc” key, or back on your remote. Depending on where you are located in Boxee, you may have to hit it a few time to “back out” to the Pop Up menu. From the Pop Up Menu, you can easily access any of the resources, settings, and favorites. Queue The Queue is your playlist of TV shows, movies, or Internet videos you wish to watch. When you find an offering you’d like to watch, select it and then click “Add to Queue.” The selected item will be added to your Queue and can be accessed at any time from the Menu. TV Show Library The TV Show library can contain files from your local hard drive or streaming content from the Web. Boxee pulls content from a variety of online locations such as Hulu and TV network sites. Click on the show to see which specific episodes are currently available. To search for your favorite shows, click on the yellow arrow to the left, or navigate to the left with your keyboard or remote. Enter your selection into the search box. My Apps By default, the “My Apps” section includes a list of the most popular apps, such as Netflix, Pandora, YouTube, and others. You can remove Apps from “My Apps,” or add new Apps from the Apps Library.   To access all the available Apps, click on the left arrow button, or click on the yellow arrow at the left, then select “App Library.” Choose an App from the Library and click it to open… … and then select “Add to My Apps.” Or, you can click start to play the App if you don’t wish to Add it to your “My Apps.”   Music, Pictures, and Movies Boxee will scan your PC for movies, pictures, and music. You can choose to scan specific folders by clicking on “Scan Media Folders…” … or from the Pop Up Menu, selecting Settings > Media, and then browsing for your media.   Conclusion Boxee to be a great way to integrate your local media with online streaming content. It can be run as an application on your home PC, or as a stand alone media PC. It should also be noted, however, that your access to online content will vary depending on your country. If you are a Windows Media Center user and and want to add the additional features of Boxee, check out our article on integrating Boxee with Windows 7 Media Center. Download Boxee Similar Articles Productive Geek Tips Integrate Boxee with Media Center in Windows 7Disable Fast User Switching on Windows XPOops! Sorry About the Feed ErrorsDisplay a list of Started Services from the Command Line (Windows)Feedburner to Google: Worst Transition Ever. TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Discover New Bundled Feeds in Google Reader Play Music in Chrome by Simply Dragging a File 15 Great Illustrations by Chow Hon Lam Easily Sync Files & Folders with Friends & Family Amazon Free Kindle for PC Download Stretch popurls.com with a Stylish Script (Firefox)

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  • Try out Windows Phone 7 on your PC today

    - by Matthew Guay
    Anticipation has been building for the new Windows Phone 7 Series ever since Microsoft unveiled it at the Mobile World Congress in February.  Now, thanks to free developer tools, you can get a first-hand experience of the basic Windows Phone 7 Series devices on your PC. Windows Phone 7 Series represents a huge change in the mobile field for Microsoft, bringing the acclaimed Zune HD UI to an innovative phone platform.  Windows Mobile has often been criticized for being behind other Smartphone platforms, but Microsoft seeks to regain the lead with this new upcoming release.  A platform must have developers behind it to be useful, so they have released a full set of free development tools so anyone can make apps for it today.  Or, if you simply want to play with Windows Phone 7, you can use the included emulator to try out the new Metro UI.  Here’s how to do this today on your Vista or 7 computer. Please note: These tools are a Customer Technology Preview release, so only install them if you’re comfortable using pre-release software. Getting Started First, download the Windows Phone Developer Tools CTP (link below), and run the installer.  This will install the Customer Technology Preview (CTP) versions of Visual Studio 2010 Express for Windows Phone, Windows Phone Emulator, Silverlight for Windows Phone, and XNA 4.0 Game Studio on your computer, all of which are required and cannot be installed individually. Accept the license agreement when prompted. Click “Install Now” to install the tools you need.  The only setup customization option is where to save the files, so choose Customize if you need to do so. Setup will now automatically download and install the components you need, and will additionally download either 32 or 64 bit programs depending on your operating system. About halfway thorough the installation, you’ll be prompted to reboot your system.  Once your computer is rebooted, setup will automatically resume without further input.   When setup is finished, click “Run the Product Now” to get started. Running Windows Phone 7 on your PC Now that you’ve got the Windows Phone Developer tools installed, it’s time to get the Windows Phone emulator running.  If you clicked “Run the Product Now” when the setup finished, Visual Studio 2010 Express for Windows Phone should have already started.   If not, simply enter “visual studio” in your start menu search and select “Microsoft Visual Studio 2010 Express for Windows Phone”. Now, to run the Windows Phone 7 emulator, we have to test an application.  So, even if you don’t know how to program, we can open a phone application template, and then test it to run the emulator.  First, click New Project on the left hand side of the front page. Any of the application templates would work for this, but here let’s select “Windows Phone Application”, and then click Ok. Here’s your new application template, which already contains the basic phone application framework.  This is where you’d start if you want to develop a Windows Phone app, but for now we just want to see Windows Phone 7 in action. So, to run the emulator, click Debug in the menu and then select Start Debugging. Your new application will launch inside the Windows Phone 7 Series emulator.  The default template doesn’t give us much, but it does show an example application running in Windows Phone 7.   Exploring Windows Phone 7 Click the Windows button on the emulator to go to the home screen.  Notice the Zune HD-like transition animation.  The emulator only includes Internet Explorer, your test application, and a few settings. Click the arrow on the right to see the available applications in a list. Settings lets you change the theme, regional settings, and the date and time in your emulator.  It also has an applications settings pane, but this currently isn’t populated. The Time settings shows a unique Windows Phone UI. You can return to the home screen by pressing the Windows button.  Here’s the Internet Explorer app running, with the virtual keyboard open to enter an address.  Please note that this emulator can also accept input from your keyboard, so you can enter addresses without clicking on the virtual keyboard. And here’s Google running in Internet Explorer on Windows Phone 7. Windows Phone 7 supports accelerometers, and you can simulate this in the emulator.  Click one of the rotate buttons to rotate the screen in that direction. Here’s our favorite website in Internet Explorer on Windows Phone 7 in landscape mode. All this, running right inside your Windows 7 desktop… Developer tools for Windows Phone 7 Although it may be fun to play with the Windows Phone 7 emulator, developers will be more excited to actually be able to create new and exciting apps for it.  The Windows Phone Developer Tools download includes Visual Studio Express and XNA Game Studio 4.0 which lets you create enticing games and apps for Windows Phones.  All development for Windows Phones will be in C#, Silverlight, and the XNA game framework.  Visual Studio Express for Windows Phone includes templates for these, and additionally has code samples to help you get started with development. Conclusion Many features are still not functional in this preview version, such as the search button and most of the included applications.  However, this still gives you a great way to experience firsthand the future of the Windows Phone platform.  And, for developers, this is your chance to set your mark on the Windows Phone 7 Series even before it is released to the public.  Happy playing and developing! Links Download Windows Phone Developer Tools CTP Windows Phone Developer Site Similar Articles Productive Geek Tips Keep Track of Homework Assignments with SoshikuWeekend Fun: Watch Television On Your PC With TVUPlayerEasily Manage Your Downloads with Download StatusbarCreate a Shortcut or Hotkey to Mute the System Volume in WindowsHow-To Geek on Lifehacker: How to Make Windows Vista Less Annoying TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Convert the Quick Launch Bar into a Super Application Launcher Automate Tasks in Linux with Crontab Discover New Bundled Feeds in Google Reader Play Music in Chrome by Simply Dragging a File 15 Great Illustrations by Chow Hon Lam Easily Sync Files & Folders with Friends & Family

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  • Developer’s Life – Summary of Superhero Articles

    - by Pinal Dave
    Earlier this year, I wrote an article series where I talked about developer’s life and compared it with Superhero. I have got amazing response to this series and I have been receiving quite a lots of email suggesting that I should write more blog post about them. Currently I am not planning to write more blog post but I will soon continue another series. In this blog post, I have summarized the entire series. Let me know if you want me to write about any superhero. I will see what I can do about that hero. Developer’s Life – Every Developer is a Captain America Captain America was first created as a comic book character in the 1940’s as a way to boost morale during World War II.  Aimed at a children’s audience, his legacy faded away when the war ended.  However, he has recently has a major reboot to become a popular movie character that deals with modern issues. Developer’s Life – Every Developer is the Incredible Hulk The Incredible Hulk is possibly one of the scariest superheroes out there.  All superheroes are meant to be “out of this world” and awe-inspiring, but I think most people will agree with I say The Hulk takes this to the next level.  He is the result of an industrial accident, which is scary enough in it’s own right.  Plus, when mild-mannered Bruce Banner is angered, he goes completely out-of-control and transforms into a destructive monster that he cannot control and has no memories of. Developer’s Life – Every Developer is a Wonder Woman We have focused a lot lately on this “superhero series.”  I love fantasy books and movies, and I feel like there is a lot to be learned from them.  As I am writing this series, though, I have noticed that every super hero I write about is a man.  So today, I would like to talk about the major female super hero – Wonder Woman. Developer’s Life – Every Developer is a Harry Potter Harry Potter might not be a superhero in the traditional sense, but I believe he still has a lot to teach us and show us about life as a developer.  If you have been living under a rock for the last 17 years, you might not know that Harry Potter is the main character in an extremely popular series of books and movies documenting the education and tribulation of a young wizard (and his friends). Developer’s Life – Every Developer is Like Transformers Transformers may not be superheroes – they don’t wear capes, they don’t have amazing powers outside of their size and folding ability, they’re not even human (technically).  Part of their enduring popularity is that while we are enjoying over-the-top movies, we are learning about good leadership and strong personal skills. Developer’s Life – Every Developer is a Iron Man Iron Man is another superhero who is not naturally “super,” but relies on his brain (and money) to turn him into a fighting machine.  While traditional superheroes are still popular, a three-movie franchise and incorporation into the new Avengers series shows that Iron Man is popular enough on his own. Developer’s Life – Every Developer is a Sherlock Holmes I have been thinking a lot about how developers are like super heroes, and I have written two blog posts now comparing them to Spiderman and Superman.  I have a lot of love and respect for developers, and I hope that they are enjoying these articles, and others are learning a little bit about the profession.  There is another fictional character who, while not technically asuper hero, is very powerful, and I also think stands as a good example of a developer. That character is Sherlock Holmes.  Sherlock Holmes is a British detective, first made popular at the turn of the 19thcentury by author Sir Arthur Conan Doyle.  The original Sherlock Holmes was a brilliant detective who could solve the most mind-boggling crime through simple observations and deduction. Developer’s Life – Every Developer is a Chhota Bheem Chhota Bheem is a cartoon character that is extremely popular where I live.  He is my daughter’s favorite characters.  I like to say that children love Chhota Bheem more than their parents – it is lucky for us he is not real!  Children love Chhota Bheem because he is the absolute “good guy.”  He is smart, loyal, and strong.  He and his friends live in Dholakpur and fight off their many enemies – and always win – in every episode.  In each episode, they learn something about friendship, bravery, and being kind to others.  Chhota Bheem is a good role model for children, and I think that he is a good role model for developers are well. Developer’s Life – Every Developer is a Batman Batman is one of the darkest superheroes in the fantasy canon.  He does not come to his powers through any sort of magical coincidence or radioactive insect, but through a lot of psychological scarring caused by witnessing the death of his parents.  Despite his dark back story, he possesses a lot of admirable abilities that I feel bear comparison to developers. Developer’s Life – Every Developer is a Superman I enjoyed comparing developers to Spiderman so much, that I have decided to continue the trend and encourage some of my favorite people (developers) with another favorite superhero – Superman.  Superman is probably the most famous superhero – and one of the most inspiring. Developer’s Life – Every Developer is a Spiderman I have to admit, Spiderman is my favorite superhero.  The most recent movie recently was released in theaters, so it has been at the front of my mind for some time. Spiderman was my favorite superhero even before the latest movie came out, but of course I took my whole family to see the movie as soon as I could!  Every one of us loved it, including my daughter.  We all left the movie thinking how great it would be to be Spiderman.  So, with that in mind, I started thinking about how we are like Spiderman in our everyday lives, especially developers. I would like to know which Superhero is your favorite hero! Reference: Pinal Dave (http://blog.SQLAuthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: Developer, Superhero

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  • Displaying an image on a LED matrix with a Netduino

    - by Bertrand Le Roy
    In the previous post, we’ve been flipping bits manually on three ports of the Netduino to simulate the data, clock and latch pins that a shift register expected. We did all that in order to control one line of a LED matrix and create a simple Knight Rider effect. It was rightly pointed out in the comments that the Netduino has built-in knowledge of the sort of serial protocol that this shift register understands through a feature called SPI. That will of course make our code a whole lot simpler, but it will also make it a whole lot faster: writing to the Netduino ports is actually not that fast, whereas SPI is very, very fast. Unfortunately, the Netduino documentation for SPI is severely lacking. Instead, we’ve been reliably using the documentation for the Fez, another .NET microcontroller. To send data through SPI, we’ll just need  to move a few wires around and update the code. SPI uses pin D11 for writing, pin D12 for reading (which we won’t do) and pin D13 for the clock. The latch pin is a parameter that can be set by the user. This is very close to the wiring we had before (data on D11, clock on D12 and latch on D13). We just have to move the latch from D13 to D10, and the clock from D12 to D13. The code that controls the shift register has slimmed down considerably with that change. Here is the new version, which I invite you to compare with what we had before: public class ShiftRegister74HC595 { protected SPI Spi; public ShiftRegister74HC595(Cpu.Pin latchPin) : this(latchPin, SPI.SPI_module.SPI1) { } public ShiftRegister74HC595(Cpu.Pin latchPin, SPI.SPI_module spiModule) { var spiConfig = new SPI.Configuration( SPI_mod: spiModule, ChipSelect_Port: latchPin, ChipSelect_ActiveState: false, ChipSelect_SetupTime: 0, ChipSelect_HoldTime: 0, Clock_IdleState: false, Clock_Edge: true, Clock_RateKHz: 1000 ); Spi = new SPI(spiConfig); } public void Write(byte buffer) { Spi.Write(new[] {buffer}); } } All we have to do here is configure SPI. The write method couldn’t be any simpler. Everything is now handled in hardware by the Netduino. We set the frequency to 1MHz, which is largely sufficient for what we’ll be doing, but it could potentially go much higher. The shift register addresses the columns of the matrix. The rows are directly wired to ports D0 to D7 of the Netduino. The code writes to only one of those eight lines at a time, which will make it fast enough. The way an image is displayed is that we light the lines one after the other so fast that persistence of vision will give the illusion of a stable image: foreach (var bitmap in matrix.MatrixBitmap) { matrix.OnRow(row, bitmap, true); matrix.OnRow(row, bitmap, false); row++; } Now there is a twist here: we need to run this code as fast as possible in order to display the image with as little flicker as possible, but we’ll eventually have other things to do. In other words, we need the code driving the display to run in the background, except when we want to change what’s being displayed. Fortunately, the .NET Micro Framework supports multithreading. In our implementation, we’ve added an Initialize method that spins a new thread that is tied to the specific instance of the matrix it’s being called on. public LedMatrix Initialize() { DisplayThread = new Thread(() => DoDisplay(this)); DisplayThread.Start(); return this; } I quite like this way to spin a thread. As you may know, there is another, built-in way to contextualize a thread by passing an object into the Start method. For the method to work, the thread must have been constructed with a ParameterizedThreadStart delegate, which takes one parameter of type object. I like to use object as little as possible, so instead I’m constructing a closure with a Lambda, currying it with the current instance. This way, everything remains strongly-typed and there’s no casting to do. Note that this method would extend perfectly to several parameters. Of note as well is the return value of Initialize, a common technique to add some fluency to the API and enabling the matrix to be instantiated and initialized in a single line: using (var matrix = new LedMS88SR74HC595().Initialize()) The “using” in the previous line is because we have implemented IDisposable so that the matrix kills the thread and clears the display when the user code is done with it: public void Dispose() { Clear(); DisplayThread.Abort(); } Thanks to the multi-threaded version of the matrix driver class, we can treat the display as a simple bitmap with a very synchronous programming model: matrix.Set(someimage); while (button.Read()) { Thread.Sleep(10); } Here, the call into Set returns immediately and from the moment the bitmap is set, the background display thread will constantly continue refreshing no matter what happens in the main thread. That enables us to wait or read a button’s port on the main thread knowing that the current image will continue displaying unperturbed and without requiring manual refreshing. We’ve effectively hidden the implementation of the display behind a convenient, synchronous-looking API. Pretty neat, eh? Before I wrap up this post, I want to talk about one small caveat of using SPI rather than driving the shift register directly: when we got to the point where we could actually display images, we noticed that they were a mirror image of what we were sending in. Oh noes! Well, the reason for it is that SPI is sending the bits in a big-endian fashion, in other words backwards. Now sure you could fix that in software by writing some bit-level code to reverse the bits we’re sending in, but there is a far more efficient solution than that. We are doing hardware here, so we can simply reverse the order in which the outputs of the shift register are connected to the columns of the matrix. That’s switching 8 wires around once, as compared to doing bit operations every time we send a line to display. All right, so bringing it all together, here is the code we need to write to display two images in succession, separated by a press on the board’s button: var button = new InputPort(Pins.ONBOARD_SW1, false, Port.ResistorMode.Disabled); using (var matrix = new LedMS88SR74HC595().Initialize()) { // Oh, prototype is so sad! var sad = new byte[] { 0x66, 0x24, 0x00, 0x18, 0x00, 0x3C, 0x42, 0x81 }; DisplayAndWait(sad, matrix, button); // Let's make it smile! var smile = new byte[] { 0x42, 0x18, 0x18, 0x81, 0x7E, 0x3C, 0x18, 0x00 }; DisplayAndWait(smile, matrix, button); } And here is a video of the prototype running: The prototype in action I’ve added an artificial delay between the display of each row of the matrix to clearly show what’s otherwise happening very fast. This way, you can clearly see each of the two images being displayed line by line. Next time, we’ll do no hardware changes, focusing instead on building a nice programming model for the matrix, with sprites, text and hardware scrolling. Fun stuff. By the way, can any of my reader guess where we’re going with all that? The code for this prototype can be downloaded here: http://weblogs.asp.net/blogs/bleroy/Samples/NetduinoLedMatrixDriver.zip

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