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• CouchDB, HDFS, HBase or which is right for my situation?

  - by Lucas

  Hello all, This question is regarding data storage systems such as CouchDB, HDFS and HBase, specifically, which is right. I am looking at making a simple and customized Document Management System for my organization. Basically, we need the ability to store some Word Documents, PDFs and other similar files. I also want to store metadata about these files (e.g., Author, Dates, etc). Usage permissions would also be handy, but that can probably be built using meta-data. I would also need the ability to full-text index. The ability to version, while not required would be extremely useful. I would like the ability to simply add hardware to expand the resources of the system and the system must support Network Attached Storage over the CIFS or NFS protocol(s). I have read about CouchDB, HDFS and HBase. My preferred programming language is C# as all of my end-users will be running Windows machines and I will want to make both web and winforms client implementations. My question is which solution best fits my needs? Based on my research it appears that CouchDB (utilizing the CouchDB-Lounge and CouchDB-Lucene) perfectly fits my needs. However, I am worried that since I have worked with CouchDB that I might be overlooking something useful for my needs in HDFS or HBase or something similar due to a bias. Any and all opinions are welcome as I am looking for the community input as I really do not want to make the wrong choice at the start of my project. Please ask if you need more information. I thank you all for your time, input and assistance.

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• Email as a view.

  - by Hal

  I've been in some discussion recently about where email (notifications, etc...) should be sent in an ASP.NET MVC application. My nemesis grin argues that it only makes sense that the email should be sent from the controller. I argue that an email is simply an alternate or augmented view through a different channel. Much like I would download a file as the payload of an ActionResult, the email is simply delivered through a different protocol. I've worked an extension method that allows me to do the following: <% Html.RenderEmail(model.FromAddress, model.ToAddress, model.Subject); %> which I actually include within my the view that is displayed on the screen. The beauty is that, based on convention, if I call RenderEmail from a parent view named MyView.ascx, I attempt to render the contents of a view named MyViewEmail.ascx, unless it is not found, in which case I simply email a copy of parent view. It certainly does make it testable (I still have an ISMTPService injected for testing), I wondered if anyone had any thoughts on whether or not this breaks from good practice. In use it has been extremely handy when we needed to easily send an email or modify the contents of the emailed results vs the browser rendered results. Thanks, Hal

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• Qt Socket blocking functions required to run in QThread where created. Any way past this?

  - by Alexander Kondratskiy

  The title is very cryptic, so here goes! I am writing a client that behaves in a very synchronous manner. Due to the design of the protocol and the server, everything has to happen sequentially (send request, wait for reply, service reply etc.), so I am using blocking sockets. Here is where Qt comes in. In my application I have a GUI thread, a command processing thread and a scripting engine thread. I create the QTcpSocket in the command processing thread, as part of my Client class. The Client class has various methods that boil down to writing to the socket, reading back a specific number of bytes, and returning a result. The problem comes when I try to directly call Client methods from the scripting engine thread. The Qt sockets randomly time out and when using a debug build of Qt, I get these warnings: QSocketNotifier: socket notifiers cannot be enabled from another thread QSocketNotifier: socket notifiers cannot be disabled from another thread Anytime I call these methods from the command processing thread (where Client was created), I do not get these problems. To simply phrase the situation: Calling blocking functions of QAbstractSocket, like waitForReadyRead(), from a thread other than the one where the socket was created (dynamically allocated), causes random behaviour and debug asserts/warnings. Anyone else experienced this? Ways around it? Thanks in advance.

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• Advice on designing and building distributed application to track vehicles

  - by dario-g

  I'm working on application for tracking vehicles. There will be about 10k or more vehicles. Each will be sending ~250bytes in each minute. Data contains gps location and everything from CAN Bus (every data that we can read from vehicle computer and dashboard). Data are sent by GSM/GPRS (using UDP protocol). Estimated rows with this data per day is ~2000k. I see there 3 main blocks. 1. Multithreaded Socket Server (MSS) - I have it. MSS stores received data to the queue (using NServiceBus). 2. Rule Processor Server (RPS) - this is core of this system. This block is responsible for parsing received data, storing in the database, processing rules, sending messages to Notifier Server (this will be sending e-mails/sms texts). Rule example. As I said between received bytes there will be information about current speed. When speed will be above 120 then: show alert in web application for specified users, send e-mail, send sms text. (There can be more than one instance of RPS). 3. Web application - allows reporting and defining rules by users, monitoring alerts, etc. I'm looking for advice how to design communication between RPS and Web application. Some questions: - Should Web application and RPS have separated databases or one central database will be enough? I have one domain model in web application. If there will be one central database then can I use the same model (objects) on RPS? So, how to send changed rules to RPS? I try to decouple this blocks as much as possible. I'm planning to create different instance of application for each client (each client will have separated database). One client will be have 10k vehicles, others only 100 vehicles.

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• Replace delimited block of text in file with the contents of another file

  - by rmarimon

  I need to write a simple script to replace a block of text in a configuration file with the contents of another file. Let's assume with have the following simplified files: server.xml <?xml version='1.0' encoding='UTF-8'?> <Server port="8005" shutdown="SHUTDOWN"> <Service name="Catalina"> <Connector port="80" protocol="HTTP/1.1"/> <Engine name="Catalina" defaultHost="localhost"> <!-- BEGIN realm --> <sometags/> <sometags/> <!-- END realm --> <Host name="localhost" appBase="webapps"/> </Engine> </Service> </Server> realm.xml <Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/> I want to run a script and have realm.xml replace the contents between the <!-- BEGIN realm --> and <!-- END realm --> lines. If realm.xml changes then whenever the script is run again it will replace the lines again with the new contents of realm.xml. This is intended to be run in /etc/init.d/tomcat on startup of the service on multiple installations on which the realm is going to be different. I'm not so sure how can I do this simply with awk or sed.

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• Tomcat 4.1.31 - HTTPS not working intermittently | "Page Cannot be Displayed" problems

  - by cedar715

  We are facing this error intermittently. If we restart the server it works for some time and again the problem start. We also have another load balanced server with similar configuration and that is working fine. The server is running on Linux box. If we do the "ps -ef" its listing the TOMCAT process. URL : https://xyz.abc.com:9234/axis/servlet/AxisServlet Following the configuration in server.xml file. <Connector className="org.apache.coyote.tomcat4.CoyoteConnector" port="9234" minProcessors="5" maxProcessors="75" enableLookups="true" acceptCount="100" debug="0" scheme="https" secure="true" useURIValidationHack="false" disableUploadTimeout="true"> <Factory className="org.apache.coyote.tomcat4.CoyoteServerSocketFactory" clientAuth="false" protocol="TLS" /> </Connector> Is it the problem with our load balancer which is forwarding most requests to this server? Is it any way related to the "maxProcessors" or "acceptCount" attributes defined in the above configuration? Is it the problem with the port number?? Does it have to do any thing with the certificate. The certificate is generated using Java Keytool. ( However, the other load balanced server is also using the same certificate and working fine) Please suggest in resolving this issue. thanks

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• Facebook XFBML Like Button incompatible with FeatureLoader script?

  - by retailevolved

  Facebook gurus, I have been implementing the Facebook Like button for a number of clients lately. To enable the Like Button, the following script has to be run: <div id="fb-root"></div> <script> window.fbAsyncInit = function() { FB.init({appId: '<?php echo Mage::helper("evlike")->getLikeConfig("ev_facebook_app_id") ?>', xfbml: true}); }; (function() { var e = document.createElement('script'); e.async = true; e.src = document.location.protocol + '//connect.facebook.net/en_US/all.js'; document.getElementById('fb-root').appendChild(e); }()); </script> It seems that this is incompatible with the following include: <script src="http://static.ak.connect.facebook.com/js/api_lib/v0.4/FeatureLoader.js.php/en_US" type="text/javascript"></script> It would make sense as I believe that the FeatureLoader performs an initialization. Is this official now? I would ask in official Facebook forums but I get an error every time I attempt to do so...

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• How to convert a printer driver to a stand-alone console application which can generate a printer fi

  - by Thorbjørn Ravn Andersen

  I have a situation where the only way to generate a certain datafile is to print it manually to FILE: under Windows and save it in a file for further processing. I would really like to have a small stand-alone program which embeds this binary printer driver so I can run it from a batch file and have it generate that binary file for me, as we can then fully automate the "save file in Visio, 'print' it and upload it to the final destination and trigger a remote test". Is this possible with a suitable Windows SDK? I am a Java programmer, so I do not know Visual Studio and the possibilities with MSDN - yet! - but I'd appreciate pointers. EDIT: I have the installation files for that printer driver, both 32 and 64 bit. Older versions may include a 16 bit driver. EDIT: The "print to FILE:" functionality is just what was recommended by the documentation. I have played a little bit with using the LPR-protocol to see what it can do. I'd still prefer the "invoke small binary" approach.

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• How can I set up a git repository on windows, and then push to/pull from it on Mac OSX

  - by Eric S.

  I'm trying to set up a Windows-based web server, but do the development work on Mac OSX. I installed freeSSHd and msysGit on the Windows server, and set up a repository where I want it. I also have git on my Mac and set up a repo there too. When I try to clone, pull from, or push to the windows repo via SSH, it gives me an error, "fatal: protocol error: bad line length character" It doesn't matter what I set the remote to in my client (Mac OSX) machine - I can point it to a folder that doesn't exist and it still gives me that error. I also tried this on a Linux box I have sitting around and it works perfectly, so it's not my Mac. I have a couple ideas: Maybe freeSSHd isn't behaving correctly (as suggested here) so I could get a different SSH server for Windows - perhaps OpenSSH Perhaps I'm typing the code that combines Mac and Windows file paths incorrectly. I tried: sudo git clone ssh://[email protected]/C:/Users/[my_username]/[remote_repo_name]/.git [destination] and sudo git clone ssh://[email protected]/C:\Users\[my_username]\[remote_repo_name]\.git [destination] I'm getting the same error with both of these. Does anybody know what's going wrong? Better yet, is there anybody out there that has managed to do what I want to do (push to and pull from a windows repository via SSH)? Thanks!

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• Service Browser for AMF calls (Flex to Java)

  - by Tehsin

  Has anyone used or is aware of a service browser to test AMF calls? I am looking for a tool similar to ZamfBrowser ( http://www.zamfbrowser.org ), but one that works for the Java environment. ZamfBrowser is geared towards AMFPHP. The idea here is to provide a service browser, that allows developers to test Java services using the AMF protocol, without having to go through the Flex UI all the time. There has got to be something out there already for this, but I can't seem to locate anything..... It's kind of funny and strange that a service browser exists for AMFPHP but not for regular AMF calls in a Java environment. I would imagine something exists under Blaze or LCDS? ... Trying to find it in the docs but can't seem to find anything .... The best alternative I can think of at the moment is to use FlexMonkey to record stuff, and then to simulate it using that....which is okay I guess but still sucks because you have to go in and create the Flex UI first, whereas with something like ZamfBrowser, you simply point it at the service calls, it tells the server-side developers if their code works, etc. generates the required as3 classes for you... and makes the integration process much easier in a large team. Any help or insight would be appreciated :) Thanks!

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• Rebol Multitasking with Async: why do I get Invalid port spec

  - by Rebol Tutorial

  I tried http://www.mail-archive.com/[email protected]/msg19437.html (I just changed to www.reboltutorial.com) : do http://www.rebol.it/giesse/async-protocol.r handler: func [port [port!] state [word! error!] /local tmp cmd] [ if error? :state [print mold disarm state return true] switch state [ connect [ ; do HTTP request insert port {GET /files/2009/10/word.png HTTP/1.0^M^JHost: www.reboltutorial.com^M^J^M^J} false ] read [false] write [false] close [ ; get data data: copy port close port ;print copy/part data find data "^M^J^M^J" data: to binary! find/tail data "^M^J^M^J" other/image: attempt [load data] other/text: "" show other false ] ] ] port: open async://www.reboltutorial.com:80 port/awake: :handler view layout [ across me: box 100x100 random 255.255.255 0:00:00.5 feel [ engage: func [f a e] [ if a = 'time [ me/color: random 255.255.255 show me ] ] ] other: box 100x100 255.255.255 "Downloading image..." Return Area 208x100 "You can type here while downloading." ] ] But I'm getting this error: >> port: open async://reboltutorial.com:80 ** Access Error: Invalid port spec: async://reboltutorial.com:80 ** Near: port: open async://reboltutorial.com:80 >> port/awake: :handler ** Script Error: port has no value ** Near: port/awake: :handler

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• Altruistic network connection bandwidth estimation

  - by datenwolf

  Assume two peers Alice and Bob connected over a IP network. Alice and Bob are exchanging packets of lossy compressed data which are generated and to be consumes in real time (think a VoIP or video chat application). The service is designed to cope with as little bandwidth available, but relies on low latencies. Alice and Bob would mark their connection with an apropriate QoS profile. Alice and Bob want use a variable bitrate compression and would like to consume all of the leftover bandwidth available for the connection between them, but would voluntarily reduce the consumed bitrate depending on the state of the network. However they'd like to retain a stable link, i.e. avoid interruptions in their decoded data stream caused by congestion and the delay until the bandwidth got adjusted. However it is perfectly possible for them to loose a few packets. TL;DR: Alice and Bob want to implement a VoIP protocol from scratch, and are curious about bandwidth and congestion control. What papers and resources do you suggest for Alice and Bob to read? Mainly in the area of bandwidth estimation and congestion control.

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• what libraries or platforms should I use to build web apps that provide real-time, asynchronous data

  - by Daniel Sterling

  This is a less a question with a simple, practical answer and more a question to foster discussion on the real-time data exchange topic. I'll begin with an example: Google Wave is, at its core, a real-time asynchronous data synchronization engine. Wave supports (or plans to support) concurrent (real-time) document collaboration, disconnected (offline) document editing, conflict resolution, document history and playback with attribution, and server federation. A core part of Wave is the Operational Transformation engine: http://www.waveprotocol.org/whitepapers/operational-transform The OT engine manages document state. Changes between clients are merged and each client has a sane and consistent view of the document at all times; the final document is eventually consistent between all connected clients. My question is: is this system abstract or general enough to be used as a library or generic framework upon which to build web apps that synchronize real-time, asynchronous state in each client? Is the Wave protocol directly used by any current web applications (besides Google's client)? Would it make sense to directly use it for generic state synchronization in a web app? What other existing libraries or frameworks would you consider using when building such a web app? How much code in such an app might be domain-specific logic vs generic state synchronization logic? Or, put another way, how leaky might the state synchronization abstractions be? Comments and discussion welcomed!

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• BN_hex2bn magically segfaults in openSSL

  - by xunil154

  Greetings, this is my first post on stackoverflow, and i'm sorry if its a bit long. I'm trying to build a handshake protocol for my own project and am having issues with the server converting the clients RSA's public key to a Bignum. It works in my clent code, but the server segfaults when attempting to convert the hex value of the clients public RSA to a bignum. I have already checked that there is no garbidge before or after the RSA data, and have looked online, but i'm stuck. header segment: typedef struct KEYS { RSA *serv; char* serv_pub; int pub_size; RSA *clnt; } KEYS; KEYS keys; Initializing function: // Generates and validates the servers key /* code for generating server RSA left out, it's working */ //Set client exponent keys.clnt = 0; keys.clnt = RSA_new(); BN_dec2bn(&keys.clnt->e, RSA_E_S); // RSA_E_S contains the public exponent Problem code (in Network::server_handshake): // *Recieved an encrypted message from the network and decrypt into 'buffer' (1024 byte long)* cout << "Assigning clients RSA" << endl; // I have verified that 'buffer' contains the proper key if (BN_hex2bn(&keys.clnt->n, buffer) < 0) { Error("ERROR reading server RSA"); } cout << "clients RSA has been assigned" << endl; The program segfaults at BN_hex2bn(&keys.clnt->n, buffer) with the error (valgrind output) Invalid read of size 8 at 0x50DBF9F: BN_hex2bn (in /usr/lib/libcrypto.so.0.9.8) by 0x40F23E: Network::server_handshake() (Network.cpp:177) by 0x40EF42: Network::startNet() (Network.cpp:126) by 0x403C38: main (server.cpp:51) Address 0x20 is not stack'd, malloc'd or (recently) free'd Process terminating with default action of signal 11 (SIGSEGV) Access not within mapped region at address 0x20 at 0x50DBF9F: BN_hex2bn (in /usr/lib/libcrypto.so.0.9.8) And I don't know why it is, Im using the exact same code in the client program, and it works just fine. Any input is greatly appriciated!

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• HTTP: can GET and POST requests from a same machine come from different IPs?

  - by NoozNooz42

  I'm pretty sure I remember reading --but cannot find back the links anymore-- about this: on some ISP (including at least one big ISP in the U.S.) it is possible to have a user's GET and POST request appearing to come from different IPs. (note that this is totally programming related, and I'll give an example below) I'm not talking about having your IP adress dynamically change between two requests. I'm talking about this: IP 1: 123.45.67.89 IP 2: 101.22.33.44 The same user makes a GET, then a POST, then a GET again, then a POST again and the servers see this: - GET from IP 1 - POST from IP 2 - GET from IP 1 - POST from IP 2 So altough it's the same user, the webserver sees different IPs for the GET and the POSTs. Surely seen that HTTP is a stateless protocol this is perfectly legit right? I'd like to find back the explanation as to how/why certain ISP have their networks configured such that this may happen. I'm asking because someone asked me to implement the following IP filter and I'm pretty sure it is fundamentally broken code (breaking havoc for at least one major american ISP users). Here's a Java servlet filter that is supposed to protect against some attacks. The reasoning is that: "For any session filter checks that IP address in the request is the same that was used when session was created. So in this case session ID could not be stolen for forming fake sessions." http://www.servletsuite.com/servlets/protectsessionsflt.htm However I'm pretty sure this is inherently broken because there are ISPs where you may see GET and POST coming from different IPs. Any info on this subject is very welcome.

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• Initial text and paperclipped-URL for action in UIActivityViewController & UIActivityItemSource?

  - by Benjamin Kreeger

  Finally been making it through Apple's (rather dismal) documentation on the new UIActivityViewController class and the UIActivityItemSource protocol, and I'm trying to send different data sets to different actions called from the activity view. To simplify things, I'm looking at two things. A Facebook posting action, which should say "Check this out!" and also attach a URL to the post (with that cute little paperclip). A Twitter posting action, which should say "Check this out, with #hashtag!" and also attach that same URL (with the same paperclip). Here's the code I've got implemented right now. - (id)activityViewController:(UIActivityViewController *)activityViewController itemForActivityType:(NSString *)activityType { if ([activityType isEqualToString:UIActivityTypePostToFacebook]) { return @"Check this out!"; } else if ([activityType isEqualToString:UIActivityTypePostToTwitter]) { return @"Check this out, with #hashtag!"; } return @""; } - (id)activityViewControllerPlaceholderItem:(UIActivityViewController *)activityViewController { return @""; } And then when I set up this activity view controller (it's in the same class), this is what I do. UIActivityViewController *activityView = [[UIActivityViewController alloc] initWithActivityItems:@[self] applicationActivities:nil]; [self presentViewController:activityView animated:YES completion:nil]; My dilemma is how to attach that NSURL object. It's relatively easy when calling the iOS 6 SL-class posting modals; you just call the individual methods to attach a URL or an image. How would I go about doing this here? I'll note that instead of returning NSString objects from -activityViewController:itemForActivityType, if I return just NSURL objects, they show up with that paperclip, with no body text in the post. If I return an array of those two items, nothing shows up at all.

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• How to host WCF service and TCP server on same socket?

  - by Ole Jak

  Tooday I use ServiceHost for self hosting WCF cervices. I want to host near to my WCF services my own TCP programm for direct sockets operations (like lien to some sort of broadcasting TCP stream) I need control over namespaces (so I would be able to let my clients to send TCP streams directly into my service using some nice URLs like example.com:port/myserver/stream?id=1 or example.com:port/myserver/stream?id=anything and so that I will not be bothered with Idea of 1 client for 1 socket at one time moment, I realy want to keep my WCF services on the same port as my own server or what it is so to be able to call www.example.com:port/myWCF/stream?id=222...) Can any body please help me with this? I am using just WCF now. And I do not enjoy how it works. That is one of many resons why I want to start migration to clear TCP=) I can not use net-tcp binding or any sort of other cool WS-* binding (tooday I use the simpliest one so that my clients like Flash, AJAX, etc connect to me with ease). I needed Fast and easy in implemrnting connection protocol like one I created fore use with Sockets for real time hi ammount of data transfering. So.. Any Ideas? Please - I need help.

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• Connecting Error to Remote Oracle XE database using ASP.NET

  - by imsatasia

  Hello, I have installed Oracle XE on my Development machine and it is working fine. Then I installed Oracle XE client on my Test machine which is also working fine and I can access Development PC database from Browser. Now, I want to create an ASP.Net application which can access that Oracle XE database. I tried it too, but it always shows me an error on my TEST machine to connect database to the Development Machine using ASP.Net. Here is my code for ASP.Net application: protected void Page_Load(object sender, EventArgs e) { string connectionString = GetConnectionString(); OracleConnection connection = new OracleConnection(connectionString); connection.Open(); Label1.Text = "State: " + connection.State; Label1.Text = "ConnectionString: " + connection.ConnectionString; OracleCommand command = connection.CreateCommand(); string sql = "SELECT * FROM Users"; command.CommandText = sql; OracleDataReader reader = command.ExecuteReader(); while (reader.Read()) { string myField = (string)reader["nID"]; Console.WriteLine(myField); } } static private string GetConnectionString() { // To avoid storing the connection string in your code, // you can retrieve it from a configuration file. return "User Id=System;Password=admin;Data Source=(DESCRIPTION=" + "(ADDRESS=(PROTOCOL=TCP)(HOST=myServerAddress)(PORT=1521))" + "(CONNECT_DATA=(SERVICE_NAME=)));"; }

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• Is this a good job description? What title would you give this position?

  - by Zack Peterson

  Department: Information Technology Reports To: Chief Information Officer Purpose: Company's ________________ is specifically engaged in the development of World Wide Web applications and distributed network applications. This person is concerned with all facets of the software development process and specializes in software product management. He or she contributes to projects in an application architect role and also performs individual programming tasks. Essential Duties & Responsibilities: This person is involved in all aspects of the software development process such as: Participation in software product definitions, including requirements analysis and specification Development and refinement of simulations or prototypes to confirm requirements Feasibility and cost-benefit analysis, including the choice of architecture and framework Application and database design Implementation (e.g. installation, configuration, customization, integration, data migration) Authoring of documentation needed by users and partners Testing, including defining/supporting acceptance testing and gathering feedback from pre-release testers Participation in software release and post-release activities, including support for product launch evangelism (e.g. developing demonstrations and/or samples) and subsequent product build/release cycles Maintenance Qualifications: Bachelor's degree in computer science or software engineering Several years of professional programming experience Proficiency in the general technology of the World Wide Web: Hypertext Transfer Protocol (HTTP) Hypertext Markup Language (HTML) JavaScript Cascading Style Sheets (CSS) Proficiency in the following principles, practices, and techniques: Accessibility Interoperability Usability Security (especially prevention of SQL injection and cross-site scripting (XSS) attacks) Object-oriented programming (e.g. encapsulation, inheritance, modularity, polymorphism, etc.) Relational database design (e.g. normalization, orthogonality) Search engine optimization (SEO) Asynchronous JavaScript and XML (AJAX) Proficiency in the following specific technologies utilized by Company: C# or Visual Basic .NET ADO.NET (including ADO.NET Entity Framework) ASP.NET (including ASP.NET MVC Framework) Windows Presentation Foundation (WPF) Language Integrated Query (LINQ) Extensible Application Markup Language (XAML) jQuery Transact-SQL (T-SQL) Microsoft Visual Studio Microsoft Internet Information Services (IIS) Microsoft SQL Server Adobe Photoshop

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• error detection/correction/recovery in serial protocols

  - by Jason S

  I have some designing to do for a serial protocol and am running into some questions that I figure must have been considered elsewhere. So I'm wondering if there are some recommendations for best practices in designing serial protocols. (Please either state a fact that is easily verifiable, or cite a reputable source if you make a claim.) General recommendations for websites/books are also welcome. In particular I have to deal with issues like parsing a stream of bytes into packets verifying a packet is correct (easy with a CRC, for instance) identifying reasonable types of errors that can occur (e.g. in a point-to-point serial stream, sporadic single bit errors, and dropped series of bytes, are both likely, but extra phantom bytes are unlikely; whereas with a record stored in flash memory or on a disk drive the types of errors that predominate are different) error correction or recovery (if I detect an error in a packet, can I correct it? If not, can I resync to the boundary of the next packet?) how to make variable-length packets robust to error correction / recovery. Any suggestions?

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• Correct initialization sequence for Linux serial port

  - by whitequark

  I wrote an application that must use serial ports on Linux, especially ttyUSB ones. Reading and writing operations are performed with standard select()/read() loop and write(), and there is probably nothing wrong in them, but initialization code (or absence of some part of it) damages something in the tty subsystem. Here it is: vuxboot(string filename, unsigned baud = B115200) : _debug(false) { _fd = open(filename.c_str(), O_RDWR | O_NOCTTY); if(!_fd) throw new io_error("cannot open port"); // Serial initialization was written with FTDI USB-to-serial converters // in mind. Anyway, who wants to use non-8n1 protocol? tcgetattr(_fd, &_termios); termios tio = {0}; tio.c_iflag = IGNPAR; tio.c_oflag = 0; tio.c_cflag = baud | CLOCAL | CREAD | CS8; tio.c_lflag = 0; tcflush(_fd, TCIFLUSH); tcsetattr(_fd, TCSANOW, &tio); } Another tcsetattr(_fd, TCSANOW, &_termios) sits in the destructor, but it is irrelevant. With or without this termios initialization, strange things happen in system after the application exits. Sometimes plain cat (or hd) exits immediately printing nothing or same stuff each time, sometimes it is waiting and not displaying any of the data that is surely sent onto the port; and close() (read() too, but not every time) emits a strange WARNING to dmesg referring to usb-serial.c. I checked the hardware and firmware tens of times (even on different machines) and I am sure it is working as intended; moreover, I stripped the firmware to just print same message over and over. How can I use serial port without destroying anything? Thanks.

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• Every subsequent call to an Axis webservice fails

  - by cudiaco

  I've been having a strange issue with an Axis webservice which is called through the https protocol. Basically, when an invocation is made, the call goes through just fine. If the call is made again, the web service fails, returning me with the following message: <soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <soapenv:Body> <soapenv:Fault> <faultcode>soapenv:Server.userException</faultcode> <faultstring>org.xml.sax.SAXParseException: Unexpected end of file after null</faultstring> <detail> <ns1:hostname xmlns:ns1="http://xml.apache.org/axis/">f0s0</ns1:hostname> </detail> </soapenv:Fault> </soapenv:Body> </soapenv:Envelope> When tested locally (through http), the service works perfectly fine. Has anyone encountered an issue like this before? Any help is appreciated.

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• Can I perform a search on mail server in Java?

  - by twofivesevenzero

  I am trying to perform a search of my gmail using Java. With JavaMail I can do a message by message search like so: Properties props = System.getProperties(); props.setProperty("mail.store.protocol", "imaps"); Session session = Session.getDefaultInstance(props, null); Store store = session.getStore("imaps"); store.connect("imap.gmail.com", "myUsername", "myPassword"); Folder inbox = store.getFolder("Inbox"); inbox.open(Folder.READ_ONLY); SearchTerm term = new SearchTerm() { @Override public boolean match(Message mess) { try { return mess.getContent().toString().toLowerCase().indexOf("boston") != -1; } catch (IOException ex) { Logger.getLogger(JavaMailTest.class.getName()).log(Level.SEVERE, null, ex); } catch (MessagingException ex) { Logger.getLogger(JavaMailTest.class.getName()).log(Level.SEVERE, null, ex); } return false; } }; Message[] searchResults = inbox.search(term); for(Message m:searchResults) System.out.println("MATCHED: " + m.getFrom()[0]); But this requires downloading each message. Of course I can cache all the results, but this becomes a storage concern with large gmail boxes and also would be very slow (I can only imagine how long it would take to search through gigabytes of text...). So my question is, is there a way of searching through mail on the server, a la gmail's search field? Maybe through Microsoft Exchange? Hours of Googling has turned up nothing.

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• How do I use the sed command to remove all lines between 2 phrases (including the phrases themselves

  - by fzkl

  I am generating a log from which I want to remove X startup output which looks like this: X.Org X Server 1.7.6 Release Date: 2010-03-17 X Protocol Version 11, Revision 0 Build Operating System: Linux 2.6.31-607-imx51 armv7l Ubuntu Current Operating System: Linux nvidia 2.6.33.2 #1 SMP PREEMPT Mon May 31 21:38:29 PDT 2010 armv7l Kernel command line: mem=448M@0M nvmem=64M@448M mem=512M@512M chipuid=097c81c6425f70d7 vmalloc=320M video=tegrafb console=ttyS0,57600n8 usbcore.old_scheme_first=1 tegraboot=nand root=/dev/nfs ip=:::::usb0:on rw tegra_ehci_probe_delay=5000 smp dvfs tegrapart=recovery:1b80:a00:800,boot:2680:1000:800,environment:3780:40:800,system:38c0:2bc00:800,cache:2f5c0:4000:800,userdata:336c0:c840:800 envsector=3080 Build Date: 23 April 2010 05:19:26PM xorg-server 2:1.7.6-2ubuntu7 (Bryce Harrington <[email protected]>) Current version of pixman: 0.16.4 Before reporting problems, check http://wiki.x.org to make sure that you have the latest version. Markers: (--) probed, (**) from config file, (==) default setting, (++) from command line, (!!) notice, (II) informational, (WW) warning, (EE) error, (NI) not implemented, (??) unknown. (==) Log file: "/var/log/Xorg.0.log", Time: Wed Jun 16 19:52:00 2010 (==) Using config file: "/etc/X11/xorg.conf" (==) Using config directory: "/usr/lib/X11/xorg.conf.d" Is there any way to do this without manually checking pattern for each line?

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• How to flush DNS cache in Windows Mobile programmatically?

  - by Bounded

  Hello, My windows mobile application (written in C# with the compact framework) needs to know if a particular machine is active or not. To achieve this goal, I thought to use a ping mechanism. I tried to use the Ping class implemented in the opennetcf framework (the System.Net.NetworkInformation.Ping class for the .NET Framework is not part of the compact framework). Because I give to the Ping.Send function a host name, it first tries to resolve this host name and to retrieve an IP address. But i observe the following problem : If the first dns resolution fails (because the network is down at this moment), and if the application tries immediately again to send the ping, it fails too, even if the network is note down anymore. I check with a famous network protocol analyzer and i saw that only the requests concerning the first dns resolution are sent. The requests concerning the dns resolution of the second ping are not sent. Why is the second dns request not sent ? Is there any dns cache mechanism on such Windows Mobile devices ? If yes, can this mechanism beeing flushed programmatically ? EDIT : I gave up finding a solution to this DNS flush. I chose to ping an IP adress instead of a name machine. The problem of pinging an hard coded adress IP is that we have to be 100% sure that this IP will not change. The gateway IP can be used because it's always reachable (if it does not, it means the network is down).

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