Search Results

Search found 15930 results on 638 pages for 'ui thread'.

Page 309/638 | < Previous Page | 305 306 307 308 309 310 311 312 313 314 315 316  | Next Page >

  • Parallel processing from a command queue on Linux (bash, python, ruby... whatever)

    - by mlambie
    I have a list/queue of 200 commands that I need to run in a shell on a Linux server. I only want to have a maximum of 10 processes running (from the queue) at once. Some processes will take a few seconds to complete, other processes will take much longer. When a process finishes I want the next command to be "popped" from the queue and executed. Does anyone have code to solve this problem? Further elaboration: There's 200 pieces of work that need to be done, in a queue of some sort. I want to have at most 10 pieces of work going on at once. When a thread finishes a piece of work it should ask the queue for the next piece of work. If there's no more work in the queue, the thread should die. When all the threads have died it means all the work has been done. The actual problem I'm trying to solve is using imapsync to synchronize 200 mailboxes from an old mail server to a new mail server. Some users have large mailboxes and take a long time tto sync, others have very small mailboxes and sync quickly.

    Read the article

  • Why I can't get all UDP packets?

    - by Jack
    My program use UdpClient to try to receive 27 responses from 27 hosts. The size of the response is 10KB. My broadband incoming bandwidth is 150KB/s. The 27 responses are sent from the hosts almost at the same time and for every 10 secs. However, I can only receive 8 - 17 responses each time. The number of responses that I can receive is quite dynamic but within the range. Can anyone tell me why? why can't I receive all? I understand UDP is not reliable. but I tried receiving 5 - 10 responses at the same time, it worked. I guess the network links are not so bad. The code is very simple. ON the 27 hosts, I just use UdpClient to send 10KB to my machine. On my machine, I have one UdpClient receive datagrams. Each time I get a data, I create a thread to handle it (basically handling it means just print out "I received 10KB", but it runs in a thread). listener = new UDPListener(Port); listener.Start(); while (true) { try { UDPContext context = listener.Accept(); ThreadPool.QueueUserWorkItem(new WaitCallback(HandleMessage), context); } catch (Exception) { } } If I reduce the size of the response down to 3KB, the case gets much better that roughly 25 responses can be received. Any more idea? UDP buffer problems???

    Read the article

  • What library to choose to build a user interface for a C++ software that uses SDL

    - by Barth
    Dear all, I have a simulation software (C++) that runs on the command line. It is platform independent (currently compiling and running on Windows, MacOS X and Linux). When the simulation ends, I visualize the result with SDL; it is a very basic 2d view, mainly color squares next to each other. I would like to have a user interface on top of the simulation so that I can start and pause the simulation, and change the parameters on the fly. Something pretty simple I guess. Well, ideally I will also add a grapher somewhere to see the evolution over time of some parameters. Now, I am wondering what direction I should go. Should I try to use one of the UI libraries for SDL ? Or maybe wxwidget in conjunction with SDL ? Or simply wxwidget and get rid of SDL ? Do you have any experience with this ? Thanks in advance Barth PS: I tried to use AGAR, a SDL UI library. It seemed very promising but I couldn't get it working. Not even the helloworld.

    Read the article

  • Compilig + testing an Android library with the JDK?

    - by Jarle Hansen
    Hi all, I am creating a library for Android that others can include in their own project. So far I have been working on it as a normal Java project with JDK 1.6 setup as system library. This works just fine in Eclipse when I add the android.jar. The issue comes when I try to my build script. I am running Gradle and doing a normal compile and test build cycle. My thoughts were that it does not matter if I compile it with a normal JDK, since this is not a standalone application. The benefits by creating a normal Java project is that Gradle does support this much better. My project also does not contain any UI at all. However, the problem is that of course android.jar and the JDK contains lots of the same classes and I think that this is what messes up my build script. Everything crashes when running the tests (the tests are in the same project under src/test/java). My question is, how should I create this project that is meant to be included in Android projects as a third party library? Should I create it as an Android project in Eclipse even though I am only creating a library that does not use any of the UI features? Also, should the tests be in a separate project? Thanks for all responses!

    Read the article

  • tiemout for a function that waits indefiinitely (like listen())

    - by Fantastic Fourier
    Hello, I'm not quite sure if it's possible to do what I'm about to ask so I thought I'd ask. I have a multi-threaded program where threads share a memory block to communicate necessary information. One of the information is termination of threads where threads constantly check for this value and when the value is changed, they know it's time for pthread_exit(). One of the threads contains listen() function and it seems to wait indefinitely. This can be problematic if there are nobody who wants to make connection and the thread needs to exit but it can't check the value whether thread needs to terminate or not since it's stuck on listen() and can't move beyond. while(1) { listen(); ... if(value == 1) pthread_exit(NULL); } My logic is something like that if it helps illustrate my point better. What I thought would solve the problem is to allow listen() to wait for a duration of time and if nothing happens, it moves on to next statement. Unfortunately, none of two args of listen() involves time limit. I'm not even sure if I'm going about the right way with multi-threaded programming, I'm not much experienced at all. So is this a good approach? Perhaps there is a better way to go about it? Thanks for any insightful comments.

    Read the article

  • Installing Plugins from Cloud p2 repository in Eclipse IDE

    - by user1495036
    I have been recently reading a lot about p2 for a requirement of mine. Most of the p2 documentation online points to p2 for RCP. My requirement is for a plugin repo. I have a plugin that is used within Eclipse IDE. I dnt want to change the repo location but based on the Eclipse Version, if the user looks for Install New Software or Check for Updates it needs to download the respective plugins. My repo currently contains all the plugins for all the versions. but i need to everytime give a different URL to my user based on the Version. For e.g i am using Eclipse 3.7(Indigo). I install the plugin thru Install New Software by adding the p2 Repo URL. Now the user decides to for some requirement move to Eclipse 3.6, I want him to connect to the same p2 Repo URL and download the plugins created for Eclipse 3.6. This is definitely possible using p2 Discovery, or i could categorize the downloads using composite repository but i dnt want to do any of these. Just want to kno is there any API that i can hold on to, so that before processing the URL and finding the updates, i can check the version of Eclipse and redirect it based on the version to an internal URL. This is possible in RCP, want to kno if i can do it in Eclipse p2 UI. All the p2 UI looks to be internal classes. Any directives would be appreciated. Malai

    Read the article

  • Type of member is not CLS-compliant

    - by John Galt
    Using Visual Studio 2008 and VB.Net: I have a working web app that uses an ASMX web service which is compiled into its separate assembly. I have another class library project compiled as a separate assembly that serves as a proxy to this web service. This all seems to work at runtime but I am getting this warning at compile time which I don't understand and would like to fix: Type of member 'wsZipeee' is not CLS-compliant I have dozens of webforms in the main project that reference the proxy class with no compile time complaints as this snippet shows: Imports System.Data Partial Class frmZipeee Inherits System.Web.UI.Page Public wsZipeee As New ProxyZipeeeService.WSZipeee.Zipeee Dim dsStandardMsg As DataSet Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load And yet I have one webform (also in the root of the main project) which gives me the "not CLS-compliant" message but yet attempts to reference the proxy class just like the other ASPX files. I get the compile time warning on the line annoted by me with 'ERROR here.. Imports System.Data Partial Class frmHome Inherits System.Web.UI.Page Public wsZipeee As New ProxyZipeeeService.WSZipeee.Zipeee ERROR here Dim dsStandardMsg As DataSet Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load This makes no sense to me. The file with the warning is called frmHome.aspx.vb; all others in the project declare things the same way and have no warning. BTW, the webservice itself returns standard datatypes: integer, string, and dataset.

    Read the article

  • How to handle window closed in the middle of a long running operation gracefully?

    - by Marek
    We have the following method called directly from the UI thread: void DoLengthyProcessing() { DoStuff(); var items = DoMoreStuff(); //do even more stuff - 200 lines of code trimmed this.someControl.PrepareForBigThing(); //someControl is a big user control //additional 100 lines of code that access this.someControl this.someControl.Finish(items); } Many of the called methods call Application.DoEvents() (and they do so many times) (do not ask me why, this is black magic written by black magic programmers and it can not be changed because everyone is scared what the impact would be) and there is also an operation running on a background thread involved in the processing. As a result, the window is not fully nonresponsive and can be closed manually during the processing. The Dispose method of the form "releases" the someControl variable by setting it to null. As a result, in case the user closes the window during the lengthy process, a null reference exception is thrown. How to handle this gracefully without just catching and logging the exception caused by disposal? Assigning the someControl instance to a temporary variable in the beginning of the method - but the control contains many subcontrols with similar disposal scheme - sets them to null and this causes null reference exceptions in other place put if (this.IsDisposed) return; calls before every access of the someControl variable. - making the already nasty long method even longer and unreadable. in Closing event, just indicate that we should close and only hide the window. Dispose it at the end of the lengthy operation. This is not very viable because there are many other methods involved (think 20K LOC for a single control) that would need to handle this mechanism as well. How to most effectively handle window disposal (by user action) in the middle of this kind of processing?

    Read the article

  • How to solve this problem with Python

    - by morpheous
    I am "porting" an application I wrote in C++ into Python. This is the current workflow: Application is started from the console Application parses CLI args Application reads an ini configuration file which specifies which plugins to load etc Application starts a timer Application iterates through each loaded plugin and orders them to start work. This spawns a new worker thread for the plugin The plugins carry out their work and when completed, they die When time interval (read from config file) is up, steps 5-7 is repeated iteratively Since I am new to Python (2 days and counting), the distinction between script, modules and packages are still a bit hazy to me, and I would like to seek advice from Pythonista as to how to implement the workflow described above, using Python as the programing language. In order to keep things simple, I have decided to leave out the time interval stuff out, and instead run the python script/scripts as a cron job instead. This is how I am thinking of approaching it: Encapsulate the whole application in a package which is executable (i.e. can be run from the command line with arguments. Write the plugins as modules (I think maybe its better to implement each module in a separate file?) I havent seen any examples of using threading in Python yet. Could someone provide a snippet of how I could spawn a thread to run a module. Also, I am not sure how to implement the concept of plugins in Python - any advice would be helpful - especially with a code snippet.

    Read the article

  • When is a try catch not a try catch?

    - by Dearmash
    I have a fun issue where during application shutdown, try / catch blocks are being seemingly ignored in the stack. I don't have a working test project (yet due to deadline, otherwise I'd totally try to repro this), but consider the following code snippet. public static string RunAndPossiblyThrow(int index, bool doThrow) { try { return Run(index); } catch(ApplicationException e) { if(doThrow) throw; } return ""; } public static string Run(int index) { if(_store.Contains(index)) return _store[index]; throw new ApplicationException("index not found"); } public static string RunAndIgnoreThrow(int index) { try { return Run(index); } catch(ApplicationException e) { } return ""; } During runtime this pattern works famously. We get legacy support for code that relies on exceptions for program control (bad) and we get to move forward and slowly remove exceptions used for program control. However, when shutting down our UI, we see an exception thrown from "Run" even though "doThrow" is false for ALL current uses of "RunAndPossiblyThrow". I've even gone so far as to verify this by modifying code to look like "RunAndIgnoreThrow" and I'll still get a crash post UI shutdown. Mr. Eric Lippert, I read your blog daily, I'd sure love to hear it's some known bug and I'm not going crazy. EDIT This is multi-threaded, and I've verified all objects are not modified while being accessed

    Read the article

  • How can I use multi-threading with a "for" or "foreach" loop?

    - by saafh
    I am trying to run the for loop in a separate thread so that the UI should be responsive and the progress bar is visible. The problem is that I don't know how to do that :). In this code, the process starts in a separate thread, but the next part of the code is executed at the same time. The messageBox is displayed and the results are never returned (e.g. the listbox's selected index property is never set). It doesn't work even if I use, "taskEx.delay()". TaskEx.Run(() => { for (int i = 0; i < sResults.Count(); i++) { if (sResults.ElementAt(i).DisplayIndexForSearchListBox.Trim().Contains(ayaStr)) { lstGoto.SelectedIndex = i; lstGoto_SelectionChanged(lstReadingSearchResults, null); IsIndexMatched = true; break; } } }); //TaskEx.delay(1000); if (IsIndexMatched == true) stkPanelGoto.Visibility = Visibility.Collapsed; else //the index didn't match { MessagePrompt.ShowMessage("The test'" + ayaStr + "' does not exist.", "Warning!"); } Could anyone please tell me how can I use multi-threading with a "for" or "foreach" loop?

    Read the article

  • Is there any point in using a volatile long?

    - by Adamski
    I occasionally use a volatile instance variable in cases where I have two threads reading from / writing to it and don't want the overhead (or potential deadlock risk) of taking out a lock; for example a timer thread periodically updating an int ID that is exposed as a getter on some class: public class MyClass { private volatile int id; public MyClass() { ScheduledExecutorService execService = Executors.newScheduledThreadPool(1); execService.scheduleAtFixedRate(new Runnable() { public void run() { ++id; } }, 0L, 30L, TimeUnit.SECONDS); } public int getId() { return id; } } My question: Given that the JLS only guarantees that 32-bit reads will be atomic is there any point in ever using a volatile long? (i.e. 64-bit). Caveat: Please do not reply saying that using volatile over synchronized is a case of pre-optimisation; I am well aware of how / when to use synchronized but there are cases where volatile is preferable. For example, when defining a Spring bean for use in a single-threaded application I tend to favour volatile instance variables, as there is no guarantee that the Spring context will initialise each bean's properties in the main thread.

    Read the article

  • pthread_join from a signal handler

    - by liv2hak
    I have a capture program which in addition do capturing data and writing it into a file also prints some statistics.The function that prints the statistics static void* report(void) { /*Print statistics*/ } is called roughly every second using an ALARM that expires every second.So The program is like void capture_program() { pthread_t report_thread while(!exit_now) { if(pthread_create(&report_thread,NULL,report,NULL)){ fprintf(stderr,"Error creating reporting thread! \n"); } /* Capturing code -------------- -------------- */ if(doreport) usleep(5); } } void *report(void *param) { while(true) { if(doreport) { doreport = 0 //access some register from hardware usleep(5) } } } The expiry of the timer sets the doreport flag.If this flag is set report() is called which clears the flag.I am using usleep to alternate between two threads in the program.This seems to work fine. I also have a signal handler to handle SIGINT (i.e CTRL+C) static void anysig(int sig) { if (sig != SIGINT) dagutil_set_signal_handler(SIG_DFL); /* Tell the main loop to exit */ exit_now = 1; return; } My question: 1) Is it safe to call pthread_join from inside the signal handler? 2) Should I use exit_now flag for the report thread as well?

    Read the article

  • grails question (sample 1 of Grails To Action book) problem with Controller and Service

    - by fegloff
    Hi, I'm doing Grails To Action sample for chapter one. Every was just fine until I started to work with Services. When I run the app I have the following error: groovy.lang.MissingPropertyException: No such property: quoteService for class: qotd.QuoteController at qotd.QuoteController$_closure3.doCall(QuoteController.groovy:14) at qotd.QuoteController$_closure3.doCall(QuoteController.groovy) at java.lang.Thread.run(Thread.java:619) Here is my groovie QuoteService class, which has an error within the definition of GetStaticQuote (ERROR: Groovy:unable to resolve class Quote) package qotd class QuoteService { boolean transactional = false def getRandomQuote() { def allQuotes = Quote.list() def randomQuote = null if (allQuotes.size() > 0) { def randomIdx = new Random().nextInt(allQuotes.size()) randomQuote = allQuotes[randomIdx] } else { randomQuote = getStaticQuote() } return randomQuote } def getStaticQuote() { return new Quote(author: "Anonymous",content: "Real Programmers Don't eat quiche") } } Controller groovie class package qotd class QuoteController { def index = { redirect(action: random) } def home = { render "<h1>Real Programmers do not each quiche!</h1>" } def random = { def randomQuote = quoteService.getRandomQuote() [ quote : randomQuote ] } def ajaxRandom = { def randomQuote = quoteService.getRandomQuote() render "<q>${randomQuote.content}</q>" + "<p>${randomQuote.author}</p>" } } Quote Class: package qotd class Quote { String content String author Date created = new Date() static constraints = { author(blank:false) content(maxSize:1000, blank:false) } } I'm doing the samples using Eclipse with grails addin. Any advice? Regards, Francisco

    Read the article

  • Problem with ScriptManager when trying to email rendered contents of ASP.NET page

    - by pandojc
    I recently added a Telerik control to an ascx that is included in an aspx page. This page has a "Send email" button, which when clicked will email the user the rendered output of the page. The Telerik control I added requires a ScriptManager, so I added that to the ascx. However, now the email button won't work. I get the following error: The control with ID 'myIdHere' requires a ScriptManager on the page. The ScriptManager must appear before any controls that need it. I know the script manager exists because the page works fine when I go that url, it is only failing when it tries to email the rendered output. Here's a code snippet, any ideas as to whether there is a problem with scriptmanager when doing this sort of thing? Page EmailPage = new EmailBasePage(); System.Web.UI.HtmlControls.HtmlForm EmailForm = new System.Web.UI.HtmlControls.HtmlForm(); EmailPage.Controls.Add(EmailForm); EmailForm.Controls.Add(contentTable); //this is the container with all the controls I want to email StringBuilder SB = new StringBuilder(); StringWriter html = new StringWriter(SB); HtmlTextWriter mhtmlWriter = new HtmlTextWriter(html); EmailPage.DesignerInitialize(); EmailPage.RenderControl(mhtmlWriter); mhtmlWriter.Close();

    Read the article

  • How expensive is a context switch? Is it better to implement a manual task switch than to rely on OS

    - by Vilx-
    The title says it all. Imagine I have two (three, four, whatever) tasks that have to run in parallel. Now, the easy way to do this would be to create separate threads and forget about it. But on a plain old single-core CPU that would mean a lot of context switching - and we all know that context switching is big, bad, slow, and generally simply Evil. It should be avoided, right? On that note, if I'm writing the software from ground up anyway, I could go the extra mile and implement my own task-switching. Split each task in parts, save the state inbetween, and then switch among them within a single thread. Or, if I detect that there are multiple CPU cores, I could just give each task to a separate thread and all would be well. The second solution does have the advantage of adapting to the number of available CPU cores, but will the manual task-switch really be faster than the one in the OS core? Especially if I'm trying to make the whole thing generic with a TaskManager and an ITask, etc?

    Read the article

  • Domain validates but won't save

    - by marko
    I have the following setup. Class, say, Car that has a CarPart (belongsTo=[car:Car]). When I'm creating a Car I also want to create som default CarParts, so I do def car = new Car(bla bla bla) def part = new CarPart(car:car) Now, when I do car.validate() or part.validate() it seems fine. But when I do if(car.save && part.save() I get this exception: 2012-03-24 14:02:21,943 [http-8080-4] ERROR util.JDBCExceptionReporter - Batch entry 0 insert into car_part (version, car_id, id) values ('0', '297', '298') was aborted. Call getNextException to see the cause. 2012-03-24 14:02:21,943 [http-8080-4] ERROR util.JDBCExceptionReporter - ERROR: value too long for type character varying(6) 2012-03-24 14:02:21,943 [http-8080-4] ERROR events.PatchedDefaultFlushEventListener - Could not synchronize database state with session org.hibernate.exception.DataException: Could not execute JDBC batch update Stacktrace follows: java.sql.BatchUpdateException: Batch entry 0 insert into car_part (version, deal_id, id) values ('0', '297', '298') was aborted. Call getNextException to see the cause. at org.postgresql.jdbc2.AbstractJdbc2Statement$BatchResultHandler.handleError(AbstractJdbc2Statement.java:2621) at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1837) at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:407) at org.postgresql.jdbc2.AbstractJdbc2Statement.executeBatch(AbstractJdbc2Statement.java:2754) at $Proxy20.flush(Unknown Source) at ristretto.DealController$_closure5.doCall(DealController.groovy:109) at ristretto.DealController$_closure5.doCall(DealController.groovy) at java.lang.Thread.run(Thread.java:722) Any ideas?

    Read the article

  • Facebook dialog appears but always says "An error has occurred"

    - by Conor James
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xmlns:fb="http://www.facebook.com/2008/fbml"> ... <head> ... <script src="http://connect.facebook.net/en_US/all.js#xfbml=1"></script> </head> <body> <div id="fb-root"></div> <fb:like id="fb-like" href="http://www.example.com" layout="button_count" show_faces="false" width="100"></fb:like> ... myscript.js: FB.ui( { method: 'stream.publish', message: 'getting educated about Facebook Connect', attachment: { name: 'Connect', caption: 'The Facebook Connect JavaScript SDK', description: ( 'A small JavaScript library that allows you to harness ' + 'the power of Facebook, bringing the user\'s identity, ' + 'social graph and distribution power to your site.' ), href: 'http://github.com/facebook/connect-js' }, action_links: [ { text: 'Code', href: 'http://github.com/facebook/connect-js' } ], user_message_prompt: 'Share your thoughts about Connect' }, function(response) { if (response && response.post_id) { alert('Post was published.'); } else { alert('Post was not published.'); } } ); I have Facebook like button on my page which works fine. But when I call the FB.ui method above from my JavaScript source, the Facebook dialog pops up but displays this error message: **An error occurred. Please try again later.** This has happened repeatedly for two days since I started trying to implement it. Not a very helpful error message. Any idea what might cause it or how to narrow down the problem?

    Read the article

  • How to Implement Backbone Java Logic Code into Android

    - by lord_sneed
    I wrote a program to work from the console in Eclipse and the terminal window in Linux. I am now transforming it into an Android app and I have the basic functionality of the Android UI done up until the point where it needs to use the logic from the Java file of the program I wrote. All of my inputs from the Java file are currently from the keyboard (from Scanners). My question is: how do I transform this to get it work with the user interaction of the app? The only input would be from the built in NumberPicker. Should I copy and paste the code from the Java program to the activity file in the onCreate method and change all of the input methods (Scanners) to work with the Android input? Or do I create variables in the activity file and pass them to the Java program (in the separate class)? (If so, how would I do that? the Java file starts from the main method: public static void main(String[] args) {) Also, will the print statements I have, System.out.println(...);, translate directly into the Android UI and print on the screen or do I have to modify those?

    Read the article

  • android progressBar problem

    - by kostas
    hi.i have a button that on click is loading rss feed.i want to load a progress bar until my list opens.i have created a progressbar,it works,but as i press the return button to return to the main menu the progress bar appears again and it doesnt stop(and not even let me see my menu).this is my code ProgressBar myProgressBar; int myProgress = 0; /** Called when the activity is first created. */ @Override public void onCreate(Bundle icicle) { super.onCreate(icicle); setContentView(R.layout.main1); Button nea = (Button) findViewById(R.id.nea); nea.setOnClickListener(new View.OnClickListener() { public void onClick (View view) { setContentView(R.layout.bar); myProgressBar=(ProgressBar)findViewById(R.id.bar); new Thread(myThread).start(); Intent myIntent = new Intent(view.getContext(), nea.class); startActivityForResult(myIntent, 0); } }); } and then,out of the onCreate private Runnable myThread = new Runnable(){ @Override public void run() { // TODO Auto-generated method stub while (myProgress<100){ try{ myHandle.sendMessage(myHandle.obtainMessage()); Thread.sleep(1000); } catch(Throwable t){ } } } Handler myHandle = new Handler(){ public void handleMessage(Message msg) { // TODO Auto-generated method stub myProgress++; myProgressBar.setProgress(myProgress); } }; };

    Read the article

  • [Java] Safe way of exposing keySet().

    - by Jake
    This must be a fairly common occurrence where I have a map and wish to thread-safely expose its key set: public MyClass { Map<String,String> map = // ... public final Set<String> keys() { // returns key set } } Now, if my "map" is not thread-safe, this is not safe: public final Set<String> keys() { return map.keySet(); } And neither is: public final Set<String> keys() { return Collections.unmodifiableSet(map.keySet()); } So I need to create a copy, such as: public final Set<String> keys() { return new HashSet(map.keySet()); } However, this doesn't seem safe either because that constructor traverses the elements of the parameter and add()s them. So while this copying is going on, a ConcurrentModificationException can happen. So then: public final Set<String> keys() { synchronized(map) { return new HashSet(map.keySet()); } } seems like the solution. Does this look right?

    Read the article

  • tcp/ip accept not returning, but client does

    - by paquetp
    server: vxworks 6.3 calls the usual socket, bind, listen, then: for (;;) { client = accept(sfd,NULL,NULL); // pass client to worker thread } client: .NET 2.0 TcpClient constructor to connect to server that takes the string hostname and int port, like: TcpClient client = new TcpClient(server_ip, port); This is working fine when the server is compiled and executed in windows (native c++). intermittently, the constructor to TcpClient will return the instance, without throwing any exception, but the accept call in vxWorks does not return with the client fd. tcpstatShow indicates no accept occurred. What could possibly make the TcpClient constructor (which calls 'Connect') return the instance, while the accept call on the server not return? It seems to be related to what the system is doing in the background - it seems more likely to get this symptom to occur when the server is busy persisting data to flash or an NFS share when the client attempts to connect, but can happen when it isn't also. I've tried adjusting priority of the thread running accept I've looked at the size of the queue in 'listen'. There's enough. The total number of file descriptors available should be enough (haven't validated this yet though, first thing in the morning)

    Read the article

  • C# threading solution for long queries

    - by Eddie
    Senerio We have an application that records incidents. An external database needs to be queried when an incident is approved by a supervisor. The queries to this external database are sometimes taking a while to run. This lag is experienced through the browser. Possible Solution I want to use threading to eliminate the simulated hang to the browser. I have used the Thread class before and heard about ThreadPool. But, I just found BackgroundWorker in this post. MSDN states: The BackgroundWorker class allows you to run an operation on a separate, dedicated thread. Time-consuming operations like downloads and database transactions can cause your user interface (UI) to seem as though it has stopped responding while they are running. When you want a responsive UI and you are faced with long delays associated with such operations, the BackgroundWorker class provides a convenient solution. Is BackgroundWorker the way to go when handling long running queries? What happens when 2 or more BackgroundWorker processes are ran simultaneously? Is it handled like a pool?

    Read the article

  • Releasing Autopool crashes on iOS 4.0 (and only on 4.0)

    - by samsam
    Hi there. I'm wondering what could cause this. I have several methods in my code that i call using performSelectorInBackground. Within each of these methods i have an Autoreleasepool that is being alloced/initialized at the beginning and released at the end of the method. this perfectly works on iOS 3.1.3 / 3.2 / 4.2 / 4.2.1 but it fataly crashes on iOS 4.0 with a EXC_BAD_ACCESS Exception that happens after calling [myPool release]. After I noticed this strange behaviour I was thinking about rewriting portions of my code and to make my app "less parallel" in case that the client os is 4.0. After I did that, the next point where the app crashed was within the ReachabilityCallback-Method from Apples Reachability "Framework". well, now I'm not quite sure what to do. The things i do within my threaded methods is pretty simple xml parsing (no cocoa calls or stuff that would affect the UI). After each method finishes it posts a notification which the coordinating-thread listens to and once all the parallelized methods have finished, the coordinating thread calls viewcontrollers etc... I have absolutely no clue what could cause this weird behaviour. Especially because Apples Code fails as well. any help is greatly appreciated! thanks, sam

    Read the article

  • Named pipe stalls threads?

    - by entens
    I am attempting to push updates into a process via a named pipe, but in doing so my process loop now seams to stall on while ((line = sr.ReadLine()) != null). I'm a little mystified as to what might be wrong as this is my first foray into named pipes. void RefreshThread() { using (NamedPipeServerStream pipeStream = new NamedPipeServerStream("processPipe", PipeDirection.In)) { pipeStream.WaitForConnection(); using (StreamReader sr = new StreamReader(pipeStream)) { for (; ; ) { if (StopThread == true) { StopThread = false; return; // exit loop and terminate the thread } // push update for heartbeat int HeartbeatHandle = ItemDictionary["Info.Heartbeat"]; int HeartbeatValue = (int)Config.Items[HeartbeatHandle].Value; Config.Items[HeartbeatHandle].Value = ++HeartbeatValue; SetItemValue(HeartbeatHandle, HeartbeatValue, (short)0xC0, DateTime.Now); string line = null; while ((line = sr.ReadLine()) != null) { // line is in the format: item, value, timestamp string[] parts = line.Split(','); // push update and store value in item cache int handle = ItemDictionary[parts[0]]; object value = parts[1]; Config.Items[handle].Value = int.Parse(value); DateTime timestamp = DateTime.FromBinary(long.Parse(parts[2])); SetItemValue(handle, value, (short)0xC0, timestamp); } Thread.Sleep(500); } } } }

    Read the article

< Previous Page | 305 306 307 308 309 310 311 312 313 314 315 316  | Next Page >