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  • Bluetooth not detected on Asus X401A / Ubuntu 12.10

    - by Majster-pl
    I have Asus X401A ( according to specs bluetooth is build-in to this laptop, http://www.asus.com/Notebooks/Versatile_Performance/X401A/#specifications ) Bluetooth in global settings is gray ( unable to turn it on ) rfkill list output: 0: phy0: Wireless LAN Soft blocked: no Hard blocked: no 1: asus-wlan: Wireless LAN Soft blocked: no Hard blocked: no cat /var/log/dmesg | grep Blue* [ 5.895791] Bluetooth: Core ver 2.16 [ 5.895807] Bluetooth: HCI device and connection manager initialized [ 5.895809] Bluetooth: HCI socket layer initialized [ 5.895810] Bluetooth: L2CAP socket layer initialized [ 5.895814] Bluetooth: SCO socket layer initialized [ 5.909618] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [ 5.909621] Bluetooth: BNEP filters: protocol multicast [ 5.910020] Bluetooth: RFCOMM TTY layer initialized [ 5.910024] Bluetooth: RFCOMM socket layer initialized [ 5.910025] Bluetooth: RFCOMM ver 1.11 hcitool dev Devices: (empty) My wifes laptop Asus K53 have the same problem Ubuntu 12.04 LTS Any help please ?

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  • What's the difference between these Asus socket 1155 motherboards?

    - by Johnny W
    I've looked on Asus's website, but they don't make it easy to understand what the differences are, and there's so many models to choose from! It's all spiel, and endless specs. How is anybody supposed to rifle through so much detail in order to make note of minor differences? If anyone already has this knowledge, I'd love to know what the major differences between these Z77 models are: P8Z77-V P8Z77-V DELUXE P8Z77-V LE P8Z77-V LE PLUS P8Z77-V LK P8Z77-V LX P8Z77-V PREMIUM P8Z77-V PRO P8Z77-V PRO/THUNDERBOLT Asus are famous for offering lots of solutions, but if there's no easy way to see the differences, how can you even consider what to buy? Their website does include a Comparison tool, but it's broken: I'm primarily interested in 1, 3, 4, 5 and 6, if that makes the task any easier. I'm sure there are people who have this knowledge. Thanks for any help.

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  • How many per-core licenses do I need?

    - by GavinPayneUK
      With SQL Server 2012, your licensing requirements can chose to use or be required to use a per-core model depending on the edition you’re deploying. This is a change to previous editions which used a per-CPU socket model that made counting how many per-CPU licences you needed easier – cores and HyperThreading didn’t influence the CPU socket count.  Any complications which people did have typically came from running SQL Server in a virtualised environment, was a vCPU a socket or did licensing...(read more)

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  • sending sms to mobile from pc using java [closed]

    - by sjohnfernandas
    hi i need to send sms from pc to mobile phone can u people guide me to achieve? i used the following code to send sms to a mobile from pc but i did not get any output and also not getting any error so guide me and point out the mistakes what i have done. package mobilesms; import java.io.; import java.util.; import javax.comm.*; import java.io.IOException; import java.util.Properties; import java.io.InputStream; import java.io.OutputStream; import java.io.DataInputStream; import java.io.FileInputStream; import java.io.DataOutputStream; import java.io.FileOutputStream; public class ReadSimple implements Runnable, SerialPortEventListener { static CommPortIdentifier portId; static Enumeration portList; OutputStream outputstream; InputStream inputStream; SerialPort serialPort; Thread readThread; public static void main(String[] args) { portList = CommPortIdentifier.getPortIdentifiers(); while (portList.hasMoreElements()) { portId = (CommPortIdentifier) portList.nextElement(); if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) { if (portId.getName().equals("COM1")) { System.out.println("Found port:COM1 "); ReadSimple reader = new ReadSimple(); } } } } public ReadSimple() { try { serialPort = (SerialPort) portId.open("ReadSimpleApp",500); } catch (PortInUseException e) { System.out.println(e); } try { inputStream = serialPort.getInputStream(); OutputStream out=serialPort.getOutputStream(); String line=""; line="AT"+"r\n"; out.write(line.trim().getBytes()); line=""; line="AT+CMGS=7639808583"+"\r\n"; out.write(line.trim().getBytes()); System.out.print(line); line="helloworld"; //line=”ATD 996544325;”+”\r\n”; out.write(line.trim().getBytes()); } catch (IOException e) { serialPort.close(); System.out.println(e); } // catch(InterruptedException E){E.printStackTrace();} try { serialPort.addEventListener(this); } catch (TooManyListenersException e) {System.out.println(e);} serialPort.notifyondataavailable(true); try { serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE); } catch (UnsupportedCommOperationException e) {System.out.println(e);} readThread = new Thread(this); readThread.start(); } public void run() { try { Thread.sleep(200); } catch (InterruptedException e) {System.out.println(e);} } public void serialEvent(SerialPortEvent event) { switch(event.getEventType()) { case SerialPortEvent.BI: case SerialPortEvent.OE: case SerialPortEvent.FE: case SerialPortEvent.PE: case SerialPortEvent.CD: case SerialPortEvent.CTS: case SerialPortEvent.DSR: case SerialPortEvent.RI: case SerialPortEvent.OUTPUT_BUFFER_EMPTY: break; case SerialPortEvent.DATA_AVAILABLE: byte[] readBuffer = new byte[10]; try { while (inputStream.available() 0) { int numBytes = inputStream.read(readBuffer); } System.out.println(new String(readBuffer)); } catch (IOException e) {System.out.println(e);} break; } } }

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  • Communicating with a remote host via HTTPS

    - by user619818
    I have developed a solution where a Java applet makes a socket connection to a port on a socket server (which happens to run on a web server). But a new client has implemented https within their LAN and so I am told communication must be via HTTPS. With standard socket communication you connect to a port on a host. But the clients HTTPS uses port 443. So will it be possible to connect to a socket server using a different port? I assume it must be possible? Any help would be much appreciated.

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  • Apple pushnotification [closed]

    - by VIVEK
    I have a PHP script located in path like /var/www/vhosts/hostname/httpdocs/webservices, I have both PHP script and .pem files there, and I have called the .pem file in the script properly, but still when I run the script , I don't get push notification , instead i get warnings such as: Warning: stream_socket_client() [function.stream-socket-client]: Unable to set local cert chain file `ck_push_test.pem'; Check that your cafile/capath settings include details of your certificate and its issuer in /var/www/vhosts/ipartyapps.com/httpdocs/webservices/testPush.php on line 12 Warning: stream_socket_client() [function.stream-socket-client]: failed to create an SSL handle in /var/www/vhosts/ipartyapps.com/httpdocs/webservices/testPush.php on line 12 Warning: stream_socket_client() [function.stream-socket-client]: Failed to enable crypto in /var/www/vhosts/ipartyapps.com/httpdocs/webservices/testPush.php on line 12 Warning: stream_socket_client() [function.stream-socket-client]: unable to connect to ssl://gateway.push.apple.com:2195 (Unknown error) in /var/www/vhosts/ipartyapps.com/httpdocs/webservices/testPush.php on line 12 Failed to connect 0 I double checked everything path, permissions and owner/group of both script and .pem files, still not getting push notification. Any suggestions please, as it's urgent.

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  • Do I have to bind an UDP socket in my client program, to receive data? (I always get WASEINVAL)...

    - by Incubbus
    Hey There, I have the following problem: I am starting WSA, then I am creating a UDP socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP) and try to recvfrom on this socket, but it always returns -1 and I get WSAEINVAL (10022)... I don´t know why?... When I bind the port, that does not happen... But it is very lame to bind the clients socket... (As far as I remember, i never had this problem before:/ )... Anyone knows why this happens?... (I am sending data to my server, which anwsers[ or at least, tries to^^])... Inc::STATS CConnection::_RecvData(sockaddr* addr, std::string &strData) { int ret, len, fromlen; //return code / length of the data / sizeof(sockaddr) char *buffer; //will hold the data char c; //recv length of the message fromlen = sizeof(sockaddr); ret = recvfrom(m_InSock, &c, 1, 0, addr, &fromlen); if(ret != 1) { #ifdef __MYDEBUG__ std::stringstream ss; ss << WSAGetLastError(); MessageBox(NULL, ss.str().c_str(), "", MB_ICONERROR | MB_OK); #endif return Inc::ERECV; }...

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  • How to launch a Windows service network process to listen to a port on a localhost socket that is vi

    - by rwired
    Here's the code (in a standard TService in Delphi): const ProcessExe = 'MyNetApp.exe'; function RunService: Boolean; var StartInfo : TStartupInfo; ProcInfo : TProcessInformation; CreateOK : Boolean; begin CreateOK := false; FillChar(StartInfo,SizeOf(TStartupInfo),#0); FillChar(ProcInfo,SizeOf(TProcessInformation),#0); StartInfo.cb := SizeOf(TStartupInfo); CreateOK := CreateProcess(nil, PChar(ProcessEXE),nil,nil,False, CREATE_NEW_PROCESS_GROUP+NORMAL_PRIORITY_CLASS, nil, PChar(InstallDir), StartInfo, ProcInfo); CloseHandle(ProcInfo.hProcess); CloseHandle(ProcInfo.hThread); Result := CreateOK; end; procedure TServicel.ServiceExecute(Sender: TService); const IntervalsBetweenRuns = 4; //no of IntTimes between checks IntTime = 250; //ms var Count: SmallInt; begin Count := IntervalsBetweenRuns; //first time run immediately while not Terminated do begin Inc(Count); if Count >= IntervalsBetweenRuns then begin Count := 0; //We check to see if the process is running, //if not we run it. That's all there is to it. //if ProcessEXE crashes, this service host will just rerun it if processExists(ProcessEXE)=0 then RunService; end; Sleep(IntTime); ServiceThread.ProcessRequests(False); end; end; MyNetApp.exe is a SOCKS5 proxy listening on port 9870. Users configure their browser to this proxy which acts as a secure-tunnel/anonymizer. All works perfectly fine on 2000/XP/2003, but on Vista/Win7 with UAC the service runs in Session0 under LocalSystem and port 9870 doesn't show up in netstat for the logged-in user or Administrator. Seems UAC is getting in my way. Is there something I can do with the SECURITY_ATTRIBUTES or CreateProcess, or is there something I can do with CreateProcessAsUser or impersonation to ensure that a network socket on a service is available to logged-in users on the system (note, this app is for mass deployment, I don't have access to user credentials, and require the user elevate their privileges to install a service on Vista/Win7)

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  • UnauthorizedAccessException on MemoryMappedFile in C# 4.

    - by Kevin Nisbet
    Hey, I wanted to play around with using a MemoryMappedFile to access an existing binary file. If this even at all possible or am I a crazy person? The idea would be to map the existing binary file directly to memory for some preferably higher-speed operations. Or to atleast see how these things worked. using System.IO.MemoryMappedFiles; System.IO.FileInfo fi = new System.IO.FileInfo(@"C:\testparsercap.pcap"); MemoryMappedFileSecurity sec = new MemoryMappedFileSecurity(); System.IO.FileStream file = fi.Open(System.IO.FileMode.Open, System.IO.FileAccess.ReadWrite, System.IO.FileShare.ReadWrite); MemoryMappedFile mf = MemoryMappedFile.CreateFromFile(file, "testpcap", fi.Length, MemoryMappedFileAccess.Read, sec, System.IO.HandleInheritability.Inheritable, true); MemoryMappedViewAccessor FileMapView = mf.CreateViewAccessor(); PcapHeader head = new PcapHeader(); FileMapView.Read<PcapHeader>(0, out head); I get System.UnauthorizedAccessException was unhandled (Message=Access to the path is denied.) on the mf.CreateViewAccessor() line. I don't think it's file-permissions, since I'm running as a nice insecure administrator user, and there aren't any other programs open that might have a read-lock on the file. This is on Vista with UAC disabled. If it's simply not possible and I missed something in the documentation, please let me know. I could barely find anything at all referencing this feature of .net 4.0 Thanks!

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  • how can convert bitmap to byte array

    - by narasimha
    hi sir i am implementing image upload in sdcard image converting bitmap in bitmap convert in bytearray i am implementing this code import java.io.ByteArrayOutputStream; import java.io.DataInputStream; import java.io.EOFException; import java.io.File; import java.io.FileDescriptor; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import android.R.array; import android.app.Activity; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.os.Bundle; import android.util.Log; import android.widget.ImageView; public class Photo extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); File f = new File("/sdcard/DCIM/1.jpg"); FileInputStream is = null; try { is = new FileInputStream(f); Bitmap bm; bm = BitmapFactory.decodeStream(is,null,null); ByteArrayOutputStream baos = new ByteArrayOutputStream(1000); bm.compress(Bitmap.CompressFormat.JPEG,75, baos); System.out.println("3........................"+bm); ImageView pic=(ImageView)this.findViewById(R.id.picview); pic.setImageBitmap(bm); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } }this code is i am implementing how can convert bitmap in byte array INFO/System.out(12658): 3........................android.graphics.Bitmap@4358e3d0 in debug this will be displayed how can retrieve bitmap to byte array

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  • How To Avoid a Perl script calling an Another Perl Script

    - by rockyurock
    Hello, i am calling a perl script client.pl from a main script to capture the output of client.pl in @output. is there anyway to avoid the use of these two files so i can use the output of client.pl in main.pl itself here is my code.... main.pl ======= my @output = readpipe("client.pl"); client.pl ========= #! /usr/bin/perl -w #use strict; use Socket; #initialize host and port my $host = shift || $FTP_SERVER; my $port = shift || $CLIENT_PORT; my $proto = getprotobyname('tcp'); #get the port address my $iaddr = inet_aton($host); my $paddr = sockaddr_in($port, $iaddr); #create the socket, connect to the port socket(SOCKET, PF_INET, SOCK_STREAM, $proto)or die "socket: $!\n"; connect(SOCKET, $paddr) or die "connect: $!\n"; my $line; while ($line = ) { print "$line\n"; } close SOCKET or die "close: $!"; /rocky..

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  • how to implement bitmap to byte array in android

    - by satyamurthy
    hi sir i am implementing image upload in sdcard image converting bitmap in bitmap convert in bytearray i am implementing this code import java.io.ByteArrayOutputStream; import java.io.DataInputStream; import java.io.EOFException; import java.io.File; import java.io.FileDescriptor; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import android.R.array; import android.app.Activity; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.os.Bundle; import android.util.Log; import android.widget.ImageView; public class Photo extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); File f = new File("/sdcard/DCIM/1.jpg"); FileInputStream is = null; try { is = new FileInputStream(f); Bitmap bm; bm = BitmapFactory.decodeStream(is,null,null); ByteArrayOutputStream baos = new ByteArrayOutputStream(1000); bm.compress(Bitmap.CompressFormat.JPEG,75, baos); System.out.println("3........................"+bm); ImageView pic=(ImageView)this.findViewById(R.id.picview); pic.setImageBitmap(bm); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } }this code is i am implementing how can convert bitmap in byte array INFO/System.out(12658): 3........................android.graphics.Bitmap@4358e3d0 in debug this will be displayed how can retrieve bitmap to byte array

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  • Jenkins slave jobs failing on "Unexpected termination of channel"

    - by Clark Wright
    I am currently seeing a set of errors across my builds. Is this expected behaviour if you loose Jenkins (say to a box crash, or a kill -9)? Or is there something worse going on (like a bad network connection)? The stack and error is: FATAL: hudson.remoting.RequestAbortedException: java.io.IOException: Unexpected termination of the channel hudson.remoting.RequestAbortedException: hudson.remoting.RequestAbortedException: java.io.IOException: Unexpected termination of the channel at hudson.remoting.Request.call(Request.java:149) at hudson.remoting.Channel.call(Channel.java:681) at hudson.remoting.RemoteInvocationHandler.invoke(RemoteInvocationHandler.java:158) at $Proxy175.join(Unknown Source) at hudson.Launcher$RemoteLauncher$ProcImpl.join(Launcher.java:861) at hudson.Launcher$ProcStarter.join(Launcher.java:345) at hudson.tasks.CommandInterpreter.perform(CommandInterpreter.java:82) at hudson.tasks.CommandInterpreter.perform(CommandInterpreter.java:58) at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:19) at hudson.model.AbstractBuild$AbstractRunner.perform(AbstractBuild.java:703) at hudson.model.Build$RunnerImpl.build(Build.java:178) at hudson.model.Build$RunnerImpl.doRun(Build.java:139) at hudson.model.AbstractBuild$AbstractRunner.run(AbstractBuild.java:473) at hudson.model.Run.run(Run.java:1410) at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46) at hudson.model.ResourceController.execute(ResourceController.java:88) at hudson.model.Executor.run(Executor.java:238) Caused by: hudson.remoting.RequestAbortedException: java.io.IOException: Unexpected termination of the channel at hudson.remoting.Request.abort(Request.java:273) at hudson.remoting.Channel.terminate(Channel.java:732) at hudson.remoting.Channel$ReaderThread.run(Channel.java:1157) Caused by: java.io.IOException: Unexpected termination of the channel at hudson.remoting.Channel$ReaderThread.run(Channel.java:1133) Caused by: java.io.EOFException at java.io.ObjectInputStream$BlockDataInputStream.peekByte(ObjectInputStream.java:2554) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1297) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:351) at hudson.remoting.Channel$ReaderThread.run(Channel.java:1127)

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  • Connect two client sockets

    - by Hernán Eche
    Good morning, let's say Java has two kind of sockets... server sockets "ServerSocket" client sockets or just "Socket" ////so Simple ! Imagine the situation of two processes: X Client <-- Y Server The server process Y : has a "ServerSocket", that is listening to a TCP port The client process X : send a connection request through a -client type- "Socket" X ////so Simple ! then the accept() method (in server Y) returns a new client type "Socket", when it occurs, great the two Sockets get "interconected", so the -client socket- in client process, is connected with the -client socket- in the server process then (reading/writing in socket X is like reading/writing in socket Y, and viceversa. ) TWO CLIENT SOCKETS GET INTERCONECTED!! ////so Simple ! BUT... (there is always a But..) What if I create the two CLIENT sockets in same process, and I want to get them "interconected" ? ////mmm Complex =(... even posible? Let's say how to have TWO CLIENT SOCKETS GET INTERCONECTED WITHOUT using an intermediate ServerSocket ? I 've solved it.. by creating two threads for continuously reading A and writing B, and other for reading B and writng A... but I think could be a better way..(or should!) (Those world-energy-consuming threads are not necessary with the client-server aproach) Any help or advice would be appreciated!! Thanks

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  • Makefile : Build in a separate directory tree

    - by Simone Margaritelli
    My project (an interpreted language) has a standard library composed by multiple files, each of them will be built into an .so dynamic library that the interpreter will load upon user request (with an import directive). Each source file is located into a subdirectory representing its "namespace", for instance : The build process has to create a "build" directory, then when each file is compiling has to create its namespace directory inside the "build" one, for instance, when compiling std/io/network/tcp.cc he run an mkdir command with mkdir -p build/std/io/network The Makefile snippet is : STDSRC=stdlib/std/hashing/md5.cc \ stdlib/std/hashing/crc32.cc \ stdlib/std/hashing/sha1.cc \ stdlib/std/hashing/sha2.cc \ stdlib/std/io/network/http.cc \ stdlib/std/io/network/tcp.cc \ stdlib/std/io/network/smtp.cc \ stdlib/std/io/file.cc \ stdlib/std/io/console.cc \ stdlib/std/io/xml.cc \ stdlib/std/type/reflection.cc \ stdlib/std/type/string.cc \ stdlib/std/type/matrix.cc \ stdlib/std/type/array.cc \ stdlib/std/type/map.cc \ stdlib/std/type/type.cc \ stdlib/std/type/binary.cc \ stdlib/std/encoding.cc \ stdlib/std/os/dll.cc \ stdlib/std/os/time.cc \ stdlib/std/os/threads.cc \ stdlib/std/os/process.cc \ stdlib/std/pcre.cc \ stdlib/std/math.cc STDOBJ=$(STDSRC:.cc=.so) all: stdlib stdlib: $(STDOBJ) .cc.so: mkdir -p `dirname $< | sed -e 's/stdlib/stdlib\/build/'` $(CXX) $< -o `dirname $< | sed -e 's/stdlib/stdlib\/build/'`/`basename $< .cc`.so $(CFLAGS) $(LDFLAGS) I have two questions : 1 - The problem is that the make command, i really don't know why, doesn't check if a file was modified and launch the build process on ALL the files no matter what, so if i need to build only one file, i have to build them all or use the command : make path/to/single/file.so Is there any way to solve this? 2 - Any way to do this in a "cleaner" way without have to distribute all the build directories with sources? Thanks

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  • help with Firefox extension

    - by Johnny Grass
    I'm writing a Firefox extension that creates a socket server which will output the active tab's URL when a client makes a connection to it. I have the following code in my javascript file: var serverSocket; function startServer() { var listener = { onSocketAccepted : function(socket, transport) { try { var outputString = gBrowser.currentURI.spec + "\n"; var stream = transport.openOutputStream(0,0,0); stream.write(outputString,outputString.length); stream.close(); } catch(ex2){ dump("::"+ex2); } }, onStopListening : function(socket, status){} }; try { serverSocket = Components.classes["@mozilla.org/network/server-socket;1"] .createInstance(Components.interfaces.nsIServerSocket); serverSocket.init(7055,true,-1); serverSocket.asyncListen(listener); } catch(ex){ dump(ex); } document.getElementById("status").value = "Started"; } startServer(); As it is, it works for multiple tabs in a single window. If I open multiple windows, it ignores the additional windows. I think it is creating a server socket for each window, but since they are using the same port, the additional sockets fail to initialize. I need it to create a server socket when the browser launches and continue running when I close the windows (Mac OS X). As it is, when I close a window but Firefox remains running, the socket closes and I have to restart firefox to get it up an running. How do I go about that?

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  • Should I close sockets from both ends?

    - by Roman
    I have the following problem. My client program monitor for availability of server in the local network (using Bonjour, but it does not rally mater). As soon as a server is "noticed" by the client application, the client tries to create a socket: Socket(serverIP,serverPort);. At some point the client can loose the server (Bonjour says that server is not visible in the network anymore). So, the client decide to close the socket, because it is not valid anymore. At some moment the server appears again. So, the client tries to create a new socket associated with this server. But! The server can refuse to create this socket since it (server) has already a socket associated with the client IP and client port. It happens because the socket was closed by the client, not by the server. Can it happen? And if it is the case, how this problem can be solved? Well, I understand that it is unlikely that the client will try to connect to the server from the same port (client port), since client selects its ports randomly. But it still can happen (just by chance). Right?

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  • How the clients (client sockets) are identified?

    - by Roman
    To my understanding by serverSocket = new ServerSocket(portNumber) we create an object which potentially can "listen" to the indicated port. By clientSocket = serverSocket.accept() we force the server socket to "listen" to its port and to "accept" a connection from any client which tries to connect to the server through the port associated with the server. When I say "client tries to connect to the server" I mean that client program executes "nameSocket = new Socket(serverIP,serverPort)". If client is trying to connect to the server, the server "accepts" this client (i.e. creates a "client socket" associated with this client). If a new client tries to connect to the server, the server creates another client socket (associated with the new client). But how the server knows if it is a "new" client or an "old" one which has already its socket? Or, in other words, how the clients are identified? By their IP? By their IP and port? By some "signatures"? What happens if an "old" client tries to use Socket(serverIP,serverIP) again? Will server create the second socket associated with this client?

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  • Cost Comparison Hard Disk Drive to Solid State Drive on Price per Gigabyte - dispelling a myth!

    - by tonyrogerson
    It is often said that Hard Disk Drive storage is significantly cheaper per GiByte than Solid State Devices – this is wholly inaccurate within the database space. People need to look at the cost of the complete solution and not just a single component part in isolation to what is really required to meet the business requirement. Buying a single Hitachi Ultrastar 600GB 3.5” SAS 15Krpm hard disk drive will cost approximately £239.60 (http://scan.co.uk, 22nd March 2012) compared to an OCZ 600GB Z-Drive R4 CM84 PCIe costing £2,316.54 (http://scan.co.uk, 22nd March 2012); I’ve not included FusionIO ioDrive because there is no public pricing available for it – something I never understand and personally when companies do this I immediately think what are they hiding, luckily in FusionIO’s case the product is proven though is expensive compared to OCZ enterprise offerings. On the face of it the single 15Krpm hard disk has a price per GB of £0.39, the SSD £3.86; this is what you will see in the press and this is what sales people will use in comparing the two technologies – do not be fooled by this bullshit people! What is the requirement? The requirement is the database will have a static size of 400GB kept static through archiving so growth and trim will balance the database size, the client requires resilience, there will be several hundred call centre staff querying the database where queries will read a small amount of data but there will be no hot spot in the data so the randomness will come across the entire 400GB of the database, estimates predict that the IOps required will be approximately 4,000IOps at peak times, because it’s a call centre system the IO latency is important and must remain below 5ms per IO. The balance between read and write is 70% read, 30% write. The requirement is now defined and we have three of the most important pieces of the puzzle – space required, estimated IOps and maximum latency per IO. Something to consider with regard SQL Server; write activity requires synchronous IO to the storage media specifically the transaction log; that means the write thread will wait until the IO is completed and hardened off until the thread can continue execution, the requirement has stated that 30% of the system activity will be write so we can expect a high amount of synchronous activity. The hardware solution needs to be defined; two possible solutions: hard disk or solid state based; the real question now is how many hard disks are required to achieve the IO throughput, the latency and resilience, ditto for the solid state. Hard Drive solution On a test on an HP DL380, P410i controller using IOMeter against a single 15Krpm 146GB SAS drive, the throughput given on a transfer size of 8KiB against a 40GiB file on a freshly formatted disk where the partition is the only partition on the disk thus the 40GiB file is on the outer edge of the drive so more sectors can be read before head movement is required: For 100% sequential IO at a queue depth of 16 with 8 worker threads 43,537 IOps at an average latency of 2.93ms (340 MiB/s), for 100% random IO at the same queue depth and worker threads 3,733 IOps at an average latency of 34.06ms (34 MiB/s). The same test was done on the same disk but the test file was 130GiB: For 100% sequential IO at a queue depth of 16 with 8 worker threads 43,537 IOps at an average latency of 2.93ms (340 MiB/s), for 100% random IO at the same queue depth and worker threads 528 IOps at an average latency of 217.49ms (4 MiB/s). From the result it is clear random performance gets worse as the disk fills up – I’m currently writing an article on short stroking which will cover this in detail. Given the work load is random in nature looking at the random performance of the single drive when only 40 GiB of the 146 GB is used gives near the IOps required but the latency is way out. Luckily I have tested 6 x 15Krpm 146GB SAS 15Krpm drives in a RAID 0 using the same test methodology, for the same test above on a 130 GiB for each drive added the performance boost is near linear, for each drive added throughput goes up by 5 MiB/sec, IOps by 700 IOps and latency reducing nearly 50% per drive added (172 ms, 94 ms, 65 ms, 47 ms, 37 ms, 30 ms). This is because the same 130GiB is spread out more as you add drives 130 / 1, 130 / 2, 130 / 3 etc. so implicit short stroking is occurring because there is less file on each drive so less head movement required. The best latency is still 30 ms but we have the IOps required now, but that’s on a 130GiB file and not the 400GiB we need. Some reality check here: a) the drive randomness is more likely to be 50/50 and not a full 100% but the above has highlighted the effect randomness has on the drive and the more a drive fills with data the worse the effect. For argument sake let us assume that for the given workload we need 8 disks to do the job, for resilience reasons we will need 16 because we need to RAID 1+0 them in order to get the throughput and the resilience, RAID 5 would degrade performance. Cost for hard drives: 16 x £239.60 = £3,833.60 For the hard drives we will need disk controllers and a separate external disk array because the likelihood is that the server itself won’t take the drives, a quick spec off DELL for a PowerVault MD1220 which gives the dual pathing with 16 disks 146GB 15Krpm 2.5” disks is priced at £7,438.00, note its probably more once we had two controller cards to sit in the server in, racking etc. Minimum cost taking the DELL quote as an example is therefore: {Cost of Hardware} / {Storage Required} £7,438.60 / 400 = £18.595 per GB £18.59 per GiB is a far cry from the £0.39 we had been told by the salesman and the myth. Yes, the storage array is composed of 16 x 146 disks in RAID 10 (therefore 8 usable) giving an effective usable storage availability of 1168GB but the actual storage requirement is only 400 and the extra disks have had to be purchased to get the  IOps up. Solid State Drive solution A single card significantly exceeds the IOps and latency required, for resilience two will be required. ( £2,316.54 * 2 ) / 400 = £11.58 per GB With the SSD solution only two PCIe sockets are required, no external disk units, no additional controllers, no redundant controllers etc. Conclusion I hope by showing you an example that the myth that hard disk drives are cheaper per GiB than Solid State has now been dispelled - £11.58 per GB for SSD compared to £18.59 for Hard Disk. I’ve not even touched on the running costs, compare the costs of running 18 hard disks, that’s a lot of heat and power compared to two PCIe cards!Just a quick note: I've left a fair amount of information out due to this being a blog! If in doubt, email me :)I'll also deal with the myth that SSD's wear out at a later date as well - that's just way over done still, yes, 5 years ago, but now - no.

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  • OMAP 3530: How fast can I toggle an IO?

    - by raj.tiwari
    I am putting together an application for OMAP 3530 SoC. This application will run some user interface code on embedded linux and invoke waveform generation code on the DSP. The DSP and Linux sides will interact over DSP/BIOS link. My questions are: What is the highest frequency at which my DSP-side code can toggle a GPIO line? If I want to toggle multiple GPIO lines at this hight rate, how fast can I go? Thanks for any insights. -Raj

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  • Writing Device Drivers for Microcontrollers, where to define IO Port pins?

    - by volting
    I always seem to encounter this dilemma when writing low level code for MCU's. I never know where to declare pin definitions so as to make the code as reusable as possible. In this case Im writing a driver to interface an 8051 to a MCP4922 12bit serial DAC. Im unsure how/where I should declare the pin definitions for The CS(chip select) and LDAC(data latch) for the DAC. At the moment there declared in the header file for the driver. Iv done a lot of research trying to figure out the best approach but havent really found anything. Im basically want to know what the best practices... if there are some books worth reading or online information, examples etc, any recommendations would be welcome. Just a snippet of the driver so you get the idea /** @brief This function is used to write a 16bit data word to DAC B -12 data bit plus 4 configuration bits @param dac_data A 12bit word @param ip_buf_unbuf_select Input Buffered/unbuffered select bit. Buffered = 1; Unbuffered = 0 @param gain_select Output Gain Selection bit. 1 = 1x (VOUT = VREF * D/4096). 0 =2x (VOUT = 2 * VREF * D/4096) */ void MCP4922_DAC_B_TX_word(unsigned short int dac_data, bit ip_buf_unbuf_select, bit gain_select) { unsigned char low_byte=0, high_byte=0; CS = 0; /**Select the chip*/ high_byte |= ((0x01 << 7) | (0x01 << 4)); /**Set bit to select DAC A and Set SHDN bit high for DAC A active operation*/ if(ip_buf_unbuf_select) high_byte |= (0x01 << 6); if(gain_select) high_byte |= (0x01 << 5); high_byte |= ((dac_data >> 8) & 0x0F); low_byte |= dac_data; SPI_master_byte(high_byte); SPI_master_byte(low_byte); CS = 1; LDAC = 0; /**Latch the Data*/ LDAC = 1; }

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  • Java MapReduce read data

    - by Tatiana
    Hi I am having following map-reduce code by which I am trying to read records from my database. There's code: import java.io.*; import java.util.ArrayList; import java.util.List; import org.apache.hadoop.fs.*; import org.apache.hadoop.io.*; import org.apache.hadoop.mapred.*; import org.apache.hadoop.mapred.lib.db.DBConfiguration; import org.apache.hadoop.mapred.lib.db.DBInputFormat; import org.apache.hadoop.mapred.lib.db.DBWritable; import org.apache.hadoop.util.*; import org.apache.hadoop.conf.*; public class Connection extends Configured implements Tool { public int run(String[] args) throws IOException { JobConf conf = new JobConf(getConf(), Connection.class); conf.setInputFormat(DBInputFormat.class); DBConfiguration.configureDB(conf, "com.sun.java.util.jar.pack.Driver", "jdbc:postgresql://localhost:5432/polyclinic", "postgres", "12345"); String[] fields = { "name" }; DBInputFormat.setInput(conf, MyRecord.class, "doctors", null, null, fields); conf.setMapOutputKeyClass(LongWritable.class); conf.setMapOutputValueClass(MyRecord.class); conf.setOutputKeyClass(LongWritable.class); conf.setOutputValueClass(TextOutputFormat.class); TextOutputFormat.setOutputPath(conf, new Path(args[0])); JobClient.runJob(conf); return 0; } public static void main(String[] args) throws Exception { int exitCode = ToolRunner.run(new Connection(), args); System.exit(exitCode); } } Class Mapper: import java.io.IOException; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapred.MapReduceBase; import org.apache.hadoop.mapred.Mapper; import org.apache.hadoop.mapred.OutputCollector; import org.apache.hadoop.mapred.Reporter; public class MyMapper extends MapReduceBase implements Mapper<LongWritable, MyRecord, Text, IntWritable> { public void map(LongWritable key, MyRecord val, OutputCollector<Text, IntWritable> output, Reporter reporter) throws IOException { output.collect(new Text(val.name), new IntWritable(1)); } } Class Record: import java.io.DataInput; import java.io.DataOutput; import java.io.IOException; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import org.apache.hadoop.io.Text; import org.apache.hadoop.io.Writable; import org.apache.hadoop.mapred.lib.db.DBWritable; class MyRecord implements Writable, DBWritable { String name; public void readFields(DataInput in) throws IOException { this.name = Text.readString(in); } public void readFields(ResultSet resultSet) throws SQLException { this.name = resultSet.getString(1); } public void write(DataOutput out) throws IOException { } public void write(PreparedStatement stmt) throws SQLException { } } After this I got error: WARN mapred.JobClient: No job jar file set. User classes may not be found. See JobConf(Class) or JobConf#setJar(String). Can you give me any suggestion how to solve this problem?

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  • SCJP Book, IO section: Is this a typo or is there a reason it would look like this?

    - by iamchuckb
    My question is about line 4, where the new PrintWriter is created with the constructor taking the FileWriter fw as a parameter. I don't understand the use of chaining the BufferedWriter bw to FileWriter if it isn't used later on in the actual writing. Can Java apply chaining in a way that bw still somehow affects the rest of the program? 16. try { 17. FileWriter fw = new FileWriter(test); 18. BufferedWriter bw = new BufferedWriter(fw, 1024); 19. PrintWriter out = new PrintWriter(fw); 20. out.println("<html><body><h1>"); 21. out.println(args[0]); 22. out.println("</h1></body></html>"); 23. out.close(); 24. bw.close(); 25. fw.close(); 26. }catch(IOException e) { 27. e.printStackTrace(); 28. } I think it is probably a typo and they meant to use bw as the parameter for PrintWriter out but like the title says, I'm new to this. Thanks to all in advance.

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