Search Results

Search found 2327 results on 94 pages for 'signal strength'.

Page 64/94 | < Previous Page | 60 61 62 63 64 65 66 67 68 69 70 71  | Next Page >

• starting 64 Bit Windows Application Development

  - by user173438

  I intend to start writing a 64 Bit Scientific Computing Application (signal processing) for Windows using Microsoft Visual Studio 2008. What should I have ready as far as a development platform is concerned? How would it be different from 32 Bit development? What could be the porting issues for a 32 Bit version that I already have (ok - this might too early to ask.. even before I start compiling)? As you might have guessed, I am looking for general directions. All pointers would be much appreciated! :) Thanks in advance..

  Read the article

• ASP.NET application stopping event?

  - by Barguast

  I have a ASP.NET application which implements a custom in-memory cache. I'm using this as opposed to ASP.NET's caching mechanism as I needed a more complex way to handle what to drop from the cache. Part of this custom cache is a separate thread which occasionally searches for data to drop from the cache whenever it gets too large. What I need to do is signal this cache maintenance thread to stop whenever the ASP.NET application 'exits'. I guess this basically amounts to when the web site is stopped in IIS. Is there a pre-existing event I can utilise to do this? Thanks.

  Read the article

• Detecting network adapter changes on the iPhone

  - by theactiveactor

  Say that there are no WIFI networks currently available and my network-enabled app is connected over 3G. How can I detect if a user has roamed into a WIFI network? I would also like to detect the case when the user is connected over WIFI and suddenly received 3G signal. In other words, I would like to be asynchronously notified of network adapter changes. I tried using the SCNetworkReachability framework asynchronously but found that for some reason, I am not receiving Wifi-related events (i.e. adapter on/off) when connected over 3G.

  Read the article

• How to preserve data integrity while minimizing the transmission size

  - by user1500578

  we have sensors in the wild that send their data to a server every day via TCP/IP, either through 3G or through satellite for the physical layer. The sensors can automatically switch from one to the other depending on their location and the quality of the signal with the local 3G operator. Given that the 3G and satellite communications are very expensive, we want to minimize the amount of data to send. But also, we want to protect ourselves from lost data. What would be the best strategy to ensure with reasonable certainty that the integrity of our data is preserved, while minimizing the amount of redundancy, i.e the amount of data transmitted ? I've read about the zfec codec, but I'm not sure if we need to transmit all the chunks, or if we need to send a hash code along each chunk.

  Read the article

• Stopping httpd causes a process started from perl CGI script to receive SIGTERM

  - by Pranav Pal

  I am running a shell script from a perl CGI script: #!/usr/bin/perl my $command = "./script.sh &"; my $pid = fork(); if (defined($pid) && $pid==0) { # background process system( $command ); } The shell script looks like this: #!/bin/sh trap 'echo trapped' 15 tail -f test.log When I run the CGI script from browser, and then stop httpd using /etc/init.d/httpd stop, the script receives a SIGTERM signal. I was expecting the script to run as a separate process and not be tied in anyway to httpd. Though I can trap the SIGTERM, I would like to understand why the script is receiving SIGTERM at all. What wrong am I doing here? I am running RHEL 5.8 and Apache HTTP server 2.4. Thanks, Pranav

  Read the article

• logrotate compress files after the postrotate script

  - by Thomas

  I have an application generating a really heavy big log file every days (~800MB a day), thus I need to compress them but since the compression takes time, I want that logrotate compress the file after reloading/sending HUP signal to the application. /var/log/myapp.log { rotate 7 size 500M compress weekly postrotate /bin/kill -HUP `cat /var/run/myapp.pid 2>/dev/null` 2>/dev/null || true endscript } Is it already the case that the compression takes place after the postrotate (which would be counter-intuitive)? If not Can anyone tell me if it's possible to do that without an extra command script (an option or some trick)? Thanks Thomas

  Read the article

• How to detect pending system shutdown on Linux?

  - by Rajorshi

  Hi, I am working on an app where I need to detect system shutdown. However, I have not found any reliable way get a notification on this event. I know that on shutdown, my app will receive a SIGTERM signal followed by a SIGKILL. What I want to know is if there is someway to query if a SIGTERM is part of a shutdown sequence? Does any one know if there is a way to query that programmatically (C API)? As far as I know, the system does not provide any other method to query for an impending shutdowm. If it does, that would solve my problem as well. I have been trying out runlevels as well, but change in runlevels seem to be instantaneous and without any prior warnings.

  Read the article

• What mutex/locking/waiting mechanism to use when writing a Chat application with Tornado Web Framewo

  - by user272973

  We're implementing a Chat server using Tornado. The premise is simple, a user makes open an HTTP ajax connection to the Tornado server, and the Tornado server answers only when a new message appears in the chat-room. Whenever the connection closes, regardless if a new message came in or an error/timeout occurred, the client reopens the connection. Looking at Tornado, the question arises of what library can we use to allow us to have these calls wait on some central object that would signal them - A_NEW_MESSAGE_HAS_ARRIVED_ITS_TIME_TO_SEND_BACK_SOME_DATA. To describe this in Win32 terms, each async call would be represented as a thread that would be hanging on a WaitForSingleObject(...) on some central Mutex/Event/etc. We will be operating in a standard Python environment (Tornado), is there something built-in we can use, do we need an external library/server, is there something Tornado recommends? Thanks

  Read the article

• CoreDumpDirectory isn't working on ubuntu; getting segmentation fault with php

  - by siran

  I'm trying to solve a segmentation fault. This message appears in my apache-error.log: [notice] child pid 3979 exit signal Segmentation fault (11) I've tried disabling some apache and php modules but I'm still getting the same error. I've also tried putting this in apache2.conf: CoreDumpDirectory /tmp/apache2-gdb-dump and then chmod 777, chown www-data... so that the server can write. I can see no core-dump files to give me a hint on the error. Does anybody have an idea why CoreDumpDirectory isn't working on Ubuntu?

  Read the article

• Tying PyQt4 QAction triggered() to local class callable doesn't seem to work. How to debug this?

  - by Jon Watte

  I create this object when I want to create a QAction. I then add this QAction to a menu: class ActionObject(object): def __init__(self, owner, command): action = QtGui.QAction(command.name, owner) self.action = action self.command = command action.setShortcut(command.shortcut) action.setStatusTip(command.name) QtCore.QObject.connect(action, QtCore.SIGNAL('triggered()'), self.triggered) def triggered(self): print("got triggered " + self.command.id + " " + repr(checked)) Unfortunately, when the menu item is selected, the 'triggered' function is not called. QtCore.QObject.connect() returns True. Nothing is printed on the console to indicate that anything is wrong, and no exception is thrown. How can I debug this? (or, what am I doing wrong?)

  Read the article

• Force close error expecting irregulary

  - by user1506019

  I have problem. I created an application which loads random layour from resources and I have problem because program shows random layout and closes , sometimes after 2 times and sometimes after a dozen, and I dont know where is a problem, I tried to run it on my phone and I added in the manifest write_external_storage permission, and still the same error.Please help me, and try to resolve this problem. here is my code in : java : package ka.ka.ka; import java.util.Random; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; public class KAMASActivity extends Activity implements OnClickListener { Button button1; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); button1 = (Button) findViewById(R.id.button1) ; button1.setOnClickListener(this); } @Override public void onClick(View v) { int min = 1; int max = 6; int i1=0; Random r = new Random(); i1 = r.nextInt(max - min + 1) + min; if(i1==1){setContentView(R.layout.image1); button1 = (Button) findViewById(R.id.button1) ; button1.setOnClickListener(this);} if(i1==2){setContentView(R.layout.image2); button1 = (Button) findViewById(R.id.button1) ; button1.setOnClickListener(this);} if(i1==3){setContentView(R.layout.image3); button1 = (Button) findViewById(R.id.button1) ; button1.setOnClickListener(this);} if(i1==4){setContentView(R.layout.image4); button1 = (Button) findViewById(R.id.button1) ; button1.setOnClickListener(this);} if(i1==5){setContentView(R.layout.image5); button1 = (Button) findViewById(R.id.button1) ; button1.setOnClickListener(this);} if(i1==6){setContentView(R.layout.image6); button1 = (Button) findViewById(R.id.button1) ; button1.setOnClickListener(this); } } Android Manifest : <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="ka.ka.ka" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="7" /> <uses-permission android:name="android.permission.ACCESS_CHECKIN_PROPERTIES" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <application android:icon="@drawable/ikona" android:label="@string/app_name" > <activity android:name=".KAMASActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest> And he is logcat : 07-10 10:58:51.062: D/ddm-heap(218): Got feature list request 07-10 10:58:51.311: D/dalvikvm(218): GC freed 506 objects / 46032 bytes in 122ms 07-10 10:59:30.081: D/AndroidRuntime(218): Shutting down VM 07-10 10:59:30.081: W/dalvikvm(218): threadid=3: thread exiting with uncaught exception (group=0x4001b188) 07-10 10:59:30.081: E/AndroidRuntime(218): Uncaught handler: thread main exiting due to uncaught exception 07-10 10:59:30.102: E/AndroidRuntime(218): java.lang.NullPointerException 07-10 10:59:30.102: E/AndroidRuntime(218): at ka.ka.ka.KAMASActivity.onClick(KAMASActivity.java:32) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.view.View.performClick(View.java:2364) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.view.View.onTouchEvent(View.java:4179) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.widget.TextView.onTouchEvent(TextView.java:6541) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.view.View.dispatchTouchEvent(View.java:3709) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 0 7-10 10:59:30.102: E/AndroidRuntime(218): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 07-10 10:59:30.102: E/AndroidRuntime(218): at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow. java:1659) 07-10 10:59:30.102: E/AndroidRuntime(218): at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1107) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.app.Activity.dispatchTouchEvent(Activity.java:2061) 07-10 10:59:30.102: E/AndroidRuntime(218): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1643) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.view.ViewRoot.handleMessage(ViewRoot.java:1691) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.os.Handler.dispatchMessage(Handler.java:99) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.os.Looper.loop(Looper.java:123) 07-10 10:59:30.102: E/AndroidRuntime(218): at android.app.ActivityThread.main(ActivityThread.java:4363) 07-10 10:59:30.102: E/AndroidRuntime(218): at java.lang.reflect.Method.invokeNative(Native Method) 07-10 10:59:30.102: E/AndroidRuntime(218): at java.lang.reflect.Method.invoke(Method.java:521) 07-10 10:59:30.102: E/AndroidRuntime(218): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860) 07-10 10:59:30.102: E/AndroidRuntime(218): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 07-10 10:59:30.102: E/AndroidRuntime(218): at dalvik.system.NativeStart.main(Native Method) 07-10 10:59:30.121: I/dalvikvm(218): threadid=7: reacting to signal 3 07-10 10:59:30.121: E/dalvikvm(218): Unable to open stack trace file '/data/anr/traces.txt': Permission denied 07-10 10:59:32.562: I/Process(218): Sending signal. PID: 218 SIG: 9

  Read the article

• can you use proxies to do load/stress testing on a server, with proxy serving as a sort of mirror?

  - by EndangeringSpecies

  suppose I want to test a server's and its web application's ability to handle many simultaneous connections well and show decent latency. So ideally I would want a thousand machines to bombard it with usage requests, but that's not practicable. So instead, can I just make a testing script with a thousand threads to run on the same server and have them perform the testing, connecting to the server via a geographically far-away proxy? My reasoning here is that the signal will have to travel realistically big distances to the proxy and back, so that sort of emulates the reality of real clients accessing the server. Then again, to take this one step further, are there prepackaged emulators/frameworks that could perform a similar test without using internet at all, just simulating the latency of the network, realistically creating all the socket connections and other resource intensive stuff etc?

  Read the article

• Passing arguments to anonymous inner classes

  - by synic

  I'm trying to make an API library for our web services, and I'm wondering if it's possible to do something like this: abstract class UserRequest(val userId: Int) { def success(message: String) def error(error: ApiError) } api.invokeRequest(new UserRequest(121) { override def success(message: String) = { // handle success } override def error(error: ApiError) = { // handle the error } } I'm talking about passing parameters to the anonymous inner class, and also overriding the two methods. I'm extremely new to Scala, and I realize my syntax might be completely wrong. I'm just trying to come up with a good design for this library before I start coding it. I'm willing to take suggestions for this, if I'm doing it the completely wrong way, or if there's a better way. The idea is that the API will take some sort of request object, use it to make a request in a thread via http, and when the response has been made, somehow signal back to the caller if the request was a success or an error. The request/error functions have to be executed on the main thread.

  Read the article

• Basic Client-Server Design for persistent connections?

  - by cam

  Here's as far as I understand it: Client & Server make connection Client sends server data Server interprets data, sends client data So on, and so forth, until client sends disconnect signal. I'm just wondering about implementation. Step 2 and 3 are confusing to me, maybe I'm over-complicating it. Is there anymore to interpreting the data than a giant switch statement? Any good books on client/server design? Specifically talking about multithreaded servers, scalability, and message design (byte 1 = header info, byte 2 = blah blah, etc)? Specifically geared towards C++.

  Read the article

• How to add "make install" target to simple Eclipse C project

  - by Jim Flood

  I have a simple Eclipse C project. Is there a way to add a "make install" target to the generated makefile? I can't seem to find the right search keywords to find any useful information in the doc or by googling (i.e. there is too much noise and no signal.) I tried creating a simple project using the autotools plug-in but without being able to find any useful doc or tutorial that starts from scratch with a single C source file, I couldn't even get the project to build. Edit: I'll take an answer based on using the autotools plug-in if I can get my project to build. I don't see how to add an include dir (-I) a link dir (-L) or additional link libs to a new Hello World autotools C project. Is there any simple autotools plug-in tutorial that covers this?

  Read the article

• Multiple Producers Single Consumer Queue

  - by Talguy

  I am new to multithreading and have designed a program that receives data from two microcontroller measuring various temperatures (Ambient and Water) and draws the data to the screen. Right now the program is singly threaded and its performance SUCKS A BIG ONE. I get basic design approaches with multithreading but not well enough to create a thread to do a task but what I don't get is how to get threads to perform seperate task and place the data into a shared data pool. I figured that I need to make a queue that has one consumer and multiple producers (would like to use std::queue). I have seen some code on the gtkmm threading docs that show a single Con/Pro queue and they would lock the queue object produce data and signal the sleeping thread that it is finished then the producer would sleep. For what I need would I need to sleep a thread, would there be data conflicts if i didn't sleep any of the threads, and would sleeping a thread cause a data signifcant data delay (I need realtime data to be drawn 30 frames a sec) How would I go about coding such a queue using the gtkmm/glibmm library.

  Read the article

• How Two Programs Can Talk To Each Other In Java?

  - by Arnon

  My first time here... I want to ?reduce? the CPU usage/ROM usage/RAM usage - in general ?speaking?, all system resources that my App use - how doesn't? :) For this reason i want to split the preferences window from the rest of the application, and let the preferences window to run as ?independent? program. The preferences program ?should? write to a Property file(not a problem at all) and to send a "update signal" to the main program - which mean, to call the update method(that i wrote) that found in the Main class. How can i call the update method in the Main program from the preferences program? Or in the other hand... There is a way to build preferences window that take system resources just when it's appear? Is this approach - of separating programs and let them talk to each other(somehow) - is a right approach for speeding up my programs? tnx

  Read the article

• Linux Kernel - Adding field to task_struct

  - by Drex

  I'm playing around with the linux kernel and added a struct field to the task_struct in sched.h. I know that can be costly but my struct is very small. I then initialize the new struct in INIT_TASK() and also re-initialize in fork.c copy_process() function so that when the INIT task or any other task creates a new process the process gets the init values. What then happens is when I try to run the kernel I get a SEGFAULT. The gdb error is: Locating the bottom of the address space ... Program received signal SIGSEGV, Segmentation fault. 0x08066ad7 in page_ok (page=) at arch/um/os-Linux/sys-i386/task_size.c:31 31 n = *address; It looks like it fails out in task_size. Is there anything else I need to do to add a field to task_struct?

  Read the article

• Hiredis waiting for message

  - by Vivek Goel

  I am using hiredis C library to connect to redis server. I am not able to figure out how to wait for new messages after subscribing to new message. My code look like: signal(SIGPIPE, SIG_IGN ); struct event_base *base = event_base_new(); redisAsyncContext *c = redisAsyncConnect("127.0.0.1", 6379); if (c->err) { /* Let *c leak for now... */ printf("Error: %s\n", c->errstr); return 1; } redisLibeventAttach(c, base); redisAsyncSetConnectCallback(c, connectCallback); redisAsyncSetDisconnectCallback(c, disconnectCallback); redisAsyncCommand(c, NULL, NULL, "SET key %b", argv[argc - 1], strlen(argv[argc - 1])); redisAsyncCommand(c, getCallback, (char*) "end-1", "GET key"); redisAsyncCommand(c, getCallback, (char*) "end-1", "SUBSCRIBE foo"); Now how to tell hiredis to wait for message on channel ?

  Read the article

• Stopping looping thread in Java

  - by halfwarp

  I'm using a thread that is continuously reading from a queue. Something like: public void run() { Object obj; while(true) { synchronized(objectsQueue) { if(objectesQueue.isEmpty()) { try { objectesQueue.wait(); } catch (InterruptedException e) { e.printStackTrace(); } obj = objectesQueue.poll(); } } // Do something with the Object obj } } What is the best way to stop this thread? I see two options: 1 - Since Thread.stop() is deprecated, I can implement a stopThisThread() method that uses a n atomic check-condition variable. 2 - Send a Death Event object or something like that to the queue. When the thread fetches a death event it exists. I prefer the 1st way, however, I don't know when to call the stopThisThread() method, as something might be on it's way to the queue and the stop signal can arrive first (not desirable). Any suggestions?

  Read the article

• QWebPage. How to handle failed request.

  - by user453482

  I want to handle failed requests (for example, with http 404 error code in reply), display my own "notfound.html" page in QWebView. But there is no simple way to handle replies with QWebView/QWebPage classes. As I see in Arora browser, for such requests uses next mechanism: QWebPage::setForwardUnsupportedContent(true), QWebPage::unsupportedContent signal and appropriate slot where you can handle qnetworkreply manually. But I cannot understand how it works, because unsupportedContent throws only when QWebPage cannot handle request scheme (like abrakadra://, ftp://, etc) or if reply consists of special header Content-Disposition: attachment. May be anybody know something about this ?

  Read the article

• Using enums or a set of classes when I know I have a finite set of different options?

  - by devoured elysium

  Let's say I have defined the following class: public abstract class Event { public DateTime Time { get; protected set; } protected Event(DateTime time) { Time = time; } } What would you prefer between this: public class AsleepEvent : Event { public AsleepEvent(DateTime time) : base(time) { } } public class AwakeEvent : Event { public AwakeEvent(DateTime time) : base(time) { } } and this: public enum StateEventType { NowAwake, NowAsleep } public class StateEvent : Event { protected StateEventType stateType; public MealEvent(DateTime time, StateEventType stateType) : base(time) { stateType = stateType; } } and why? I am generally more inclined to the first option, but I can't explain why. Is it totally the same or are any advantages in using one instead of the other? Maybe with the first method its easier to add more "states", altough in this case I am 100% sure I will only want two states: now awake, and now asleep (they signal the moments when one awakes and one falls asleep).

  Read the article

• ipod touch crashing after uploading app to device

  - by MaKo

  hi, I installed a new device (the second out of the 100), on xcode, an iPod touch but when I upload the app, the iPod crashes, apple logo shows, and gets frozen for a while, and then resusitates, in the xcode, I get the message on console: The Debugger has exited due to signal 15 (SIGTERM). I tried a simple app I made, and it loaded it, (some bouncing ball) after starting again, but tried the same with another app that plays some sounds and it shows normally, but doesnt play the sounds, questions: how to fix this issue? (in MyApp-info.plist, in bundle identifier, I have: com.yourcompany.${PRODUCT_NAME:rfc1034identifier} havent changed this, is this a problem?? 1.b. I used that conf to upload to an iPad with no problem?? Do the apps play normally sounds *.m4a, in the simulator it works!, not in the iPod, is this due to the crash or not? Thank you,, edit Im using AudioToolbox framework, the question after 1.b is 2 in my editor, but appears as 1 in the post??

  Read the article

• How to repaint another Qt class

  - by RR

  Hi all, I'm a new bit in Qt... I have a Qt GUI application (written by me), let's call it QtAPP.exe When QtAPP.exe running, I will use a QThread and QProcess to execute some external file, such as player.exe (written in native C). Here's my question: In QtAPP.exe, there are 2 classes, 1. QMainWindow - Core of QtAPP.exe 2. QThread - A thread class to execute external things For now, if I got a finished() signal in that QThread, how do I to force the QMainWindow to repaint itself ? Hope somebody can show me some tips, maybe sample code :) Any suggestion are welcome~

  Read the article

• My app crashes on Iphone SDK 3.2

  - by Mladen

  Hi Guys, My app worked ok on iPhone SDK 3.1. However, when I try to run it in 3.2 simulator, I get the following error and it crashes: bool _WebTryThreadLock(bool), 0x5148280: Tried to obtain the web lock from a thread other than the main thread or the web thread. This may be a result of calling to UIKit from a secondary thread. Crashing now... Program received signal: “EXC_BAD_ACCESS”. When I debug it, it leads me to this peace of code: - (void)LoginViewToCheckView:(id)sender { CheckViewController *tempTestController = [[CheckViewController alloc] initWithStyle:UITableViewStyleGrouped]; [tempTestController setDelegate:self]; [self setCheckViewController: tempTestController]; [tempTestController release]; [navigationController pushViewController:checkViewController animated:YES];} Other thing worth mentioning is maybe that I am calling this function from a separate thread. Any ideas what could be wrong?

  Read the article

< Previous Page | 60 61 62 63 64 65 66 67 68 69 70 71  | Next Page >