Search Results

Search found 5662 results on 227 pages for 'processor socket'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 11/227 | < Previous Page | 7 8 9 10 11 12 13 14 15 16 17 18  | Next Page >

  • On checking is a port open on the firewall?

    - by [email protected]
    Hi, well sometimes DBAs and sysadmin need to check if a particular port is "open" on the corporate firewall --i.e. *Grid Control* Will the communication between OMS and a management agent work? --One solution well consist on deploying the piece of software in question, start it and just check if everything works fine, however i find more classy trying to get that information beforeThere are several tools for doing so --i.e. nmap *like Trinity on The Matrix*, but just found a nice piece of code for establishing a socket on a parameter passed port.After running the program doing a telnet from the client machine  will be a walk in the park Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} #include <stdio.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> int main(int argc, char *argv[]) {      int sockfd, newsockfd, portno, clilen;      char buffer[256];      struct sockaddr_in serv_addr, cli_addr;      int n;      if (argc < 2) {          fprintf(stderr,"ERROR: A port must be provided. Aborting ...\n");          return 1;      }      sockfd = socket(AF_INET, SOCK_STREAM, 0);      if (sockfd < 0)          {         fprintf("ERROR: Unable to open socket. Aborting ...\n");         return 1;       }      portno = atoi(argv[1]);      serv_addr.sin_family = AF_INET;      serv_addr.sin_addr.s_addr = INADDR_ANY;      serv_addr.sin_port = htons(portno);      if (bind(sockfd, (struct sockaddr *) &serv_addr,sizeof(serv_addr)) < 0)          {               fprintf("ERROR: Unable to bind socket. Aborting ...\n");               return 1;       }      listen(sockfd,5);      clilen = sizeof(cli_addr);      newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr,&clilen);      if (newsockfd < 0)          {           fprintf("ERROR: Unable to accept connection. Aborting...\n");           return 1;        }      return 0; }Of course, you can still ask to the network guy if the port is open or notHope it helpsL

    Read the article

  • How to handle failure to release a resource which is contained in a smart pointer?

    - by cj
    How should an error during resource deallocation be handled, when the object representing the resource is contained in a shared pointer? Smart pointers are a useful tool to manage resources safely. Examples of such resources are memory, disk files, database connections, or network connections. // open a connection to the local HTTP port boost::shared_ptr<Socket> socket = Socket::connect("localhost:80"); In a typical scenario, the class encapsulating the resource should be noncopyable and polymorphic. A good way to support this is to provide a factory method returning a shared pointer, and declare all constructors non-public. The shared pointers can now be copied from and assigned to freely. The object is automatically destroyed when no reference to it remains, and the destructor then releases the resource. /** A TCP/IP connection. */ class Socket { public: static boost::shared_ptr<Socket> connect(const std::string& address); virtual ~Socket(); protected: Socket(const std::string& address); private: // not implemented Socket(const Socket&); Socket& operator=(const Socket&); }; But there is a problem with this approach. The destructor must not throw, so a failure to release the resource will remain undetected. A common way out of this problem is to add a public method to release the resource. class Socket { public: virtual void close(); // may throw // ... }; Unfortunately, this approach introduces another problem: Our objects may now contain resources which have already been released. This complicates the implementation of the resource class. Even worse, it makes it possible for clients of the class to use it incorrectly. The following example may seem far-fetched, but it is a common pitfall in multi-threaded code. socket->close(); // ... size_t nread = socket->read(&buffer[0], buffer.size()); // wrong use! Either we ensure that the resource is not released before the object is destroyed, thereby losing any way to deal with a failed resource deallocation. Or we provide a way to release the resource explicitly during the object's lifetime, thereby making it possible to use the resource class incorrectly. There is a way out of this dilemma. But the solution involves using a modified shared pointer class. These modifications are likely to be controversial. Typical shared pointer implementations, such as boost::shared_ptr, require that no exception be thrown when their object's destructor is called. Generally, no destructor should ever throw, so this is a reasonable requirement. These implementations also allow a custom deleter function to be specified, which is called in lieu of the destructor when no reference to the object remains. The no-throw requirement is extended to this custom deleter function. The rationale for this requirement is clear: The shared pointer's destructor must not throw. If the deleter function does not throw, nor will the shared pointer's destructor. However, the same holds for other member functions of the shared pointer which lead to resource deallocation, e.g. reset(): If resource deallocation fails, no exception can be thrown. The solution proposed here is to allow custom deleter functions to throw. This means that the modified shared pointer's destructor must catch exceptions thrown by the deleter function. On the other hand, member functions other than the destructor, e.g. reset(), shall not catch exceptions of the deleter function (and their implementation becomes somewhat more complicated). Here is the original example, using a throwing deleter function: /** A TCP/IP connection. */ class Socket { public: static SharedPtr<Socket> connect(const std::string& address); protected: Socket(const std::string& address); virtual Socket() { } private: struct Deleter; // not implemented Socket(const Socket&); Socket& operator=(const Socket&); }; struct Socket::Deleter { void operator()(Socket* socket) { // Close the connection. If an error occurs, delete the socket // and throw an exception. delete socket; } }; SharedPtr<Socket> Socket::connect(const std::string& address) { return SharedPtr<Socket>(new Socket(address), Deleter()); } We can now use reset() to free the resource explicitly. If there is still a reference to the resource in another thread or another part of the program, calling reset() will only decrement the reference count. If this is the last reference to the resource, the resource is released. If resource deallocation fails, an exception is thrown. SharedPtr<Socket> socket = Socket::connect("localhost:80"); // ... socket.reset();

    Read the article

  • Are parallel calls to send/recv on the same socket valid?

    - by Jay
    Can we call send from one thread and recv from another on the same socket? Can we call multiple sends parallely from different threads on the same socket? I know that a good design should avoid this, but I am not clear how these system APIs will behave. I am unable to find a good documentation also for the same. Any pointers in the direction will be helpful.

    Read the article

  • Ubuntu 12.04 gets overheated, whereas I have no heating problems on Windows 7 whatsoever

    - by G K
    I bought a new laptop which came pre-installed with Windows 7. I love working on Ubuntu and hence installed it. I can work on Windows for 6 hours at a stretch and feel the laptop being only slightly warm, but 15 minutes into running Ubuntu and my laptop is too hot. The battery also drains out very quickly on Ubuntu. 1.5 hrs of backup on Ubuntu compared to 5-6 hrs on Windows. I previously owned a Dell Inspiron N5010 and everything ran smoothly on that. No heating issues. It came with intel i3 processor. So I'm wondering whether this problem has something to do with the processor? (AMD A8) Specs: HP Pavilion G6-2005AX Laptop (APU Quad Core A8/ 4GB/ 500GB/ Win7 HB/ 1.5GB Graph) 1 GB AMD Radeon HD 7670M Dedicated 512 MB AMD Radeon HD 7640G Graphics Integrated Is there any fix for this problem? Thanks in advance. Edit: I've installed ATI proprietary drivers suggested by Ubuntu.

    Read the article

  • Socket.ReceiveAsync problem

    - by bartol
    Hi, I have a problem using SocketAsyncEventArgs model with .net sockets. Everything works great until the moment that the server wishes to close a client connection. I use following code for this: try { socket.Shutdown(SocketShutdown.Both); } catch { } // throws if client process has already closed finally { socket.Close(); } socket = null; Each connection is using two SocketAsyncEventArgs (one for send and one for receive) and after closing the connection they are returned to a pool from which they can be later reused. And here the problem starts, because when another connection is established and receive args are reused from the pool we get an exception: System.InvalidOperationException: "An asynchronous socket operation is already in progress using this SocketAsyncEventArgs instance."; at System.Net.Sockets.SocketAsyncEventArgs.StartOperationCommon(Socket socket) at System.Net.Sockets.Socket.ReceiveAsync(SocketAsyncEventArgs e) I've done some debugging and it appears that the connection closing code from the beginning of the question does not cancel Socket.ReceiveAsync operation that is in progress when the connection is closed. I've tried many combinations of Shutdown, Disconnect and Linger options for the socket but nothing worked. Any suggestions? Thanks

    Read the article

  • No feedback from Socket.SendAsync

    - by BowserKingKoopa
    I'm creating a socket and I'm trying to send data through it using SendAsync. My socket isn't connected to anything so I expected to get an error of some sort. However I get nothing. I get no indication that the send didn't work. If I use the synchronous Send method instead of the asynchronous SendAsync method I get an Exception stating that the socket isn't connected to anything. That makes sense to me. When using SendAsync the completed event doesn't ever fire and I get no indication that the send didn't work. So basically my question is how can I tell when SendAsync fails? Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); SocketAsyncEventArgs args = new SocketAsyncEventArgs(); args.SetBuffer(new byte[0], 0, 0); args.Completed += delegate(object sender, SocketAsyncEventArgs e) { Debug.WriteLine("async send complete"); Debug.WriteLine("SOCKET ERROR: " + e.SocketError); }; bool completedSynchronously = socket.SendAsync(args); if (completedSynchronously) { Debug.WriteLine("sync send complete"); Debug.WriteLine("socket error: " + args.SocketError); }

    Read the article

  • Why is my emit not getting called?

    - by cRaZiRiCaN
    The client and server connect just fine. For some reason the emit on my client is not firing correctly. I am trying to get the testEmit and testEmit2 working. This is my server: express = require 'express' mongo = require 'mongodb' app = express() server = (require 'http').createServer(app) io = (require 'socket.io').listen(server) server.listen(8080) app.use(express.static(__dirname + '/public')) # db = new mongo.Db("documentsdb", new mongo.Server("localhost", 27017, auto_reconnect: true), {safe:true}) io.sockets.on 'connection', (socket) -> console.log 'Socket.io is connected!' #This returns an array of documents sorted via date by decreasing order. (Most recent documents first.) socket.on 'loadRecentDocuments', -> console.log 'Loading most recent documents.' db.collection 'documents', (err, collection) -> collection.find().sort(dateAdded: -1).toArray (err, documents) -> #This emit is recieved at index.html where a javascript function sendDocuments manages the documents. socket.emit 'sendDocuments', documents return #The index.html provides the code data from the search box via a javascript. io.sockets.on 'findDocuments', (code) -> #Returns an array of documents with the corresponding class code. documentCodeToSearch = code console.log 'Retreaving documents with code: ' + documentCodeToSearch db.collection 'documents', (err, collection) -> collection.find(code:documentCodeToSearch).toArray (err, documents) -> socket.emit 'sendDocuments', documents return #Uploads a document to the server. documentData is sent via javascript from submit.html io.sockets.on 'addDocument', (documentData) -> console.log 'Adding document: ' + documentData db.collection 'documents', (err, collection) -> collection.insert documentData, safe: true return #Test socket.io io.sockets.on 'testEmit', -> console.log('Emit recieved.') socket.emit 'testEmit2', 'caca' return app.listen 1337 console.log "Listening on port 1337..." This is my client: <!doctype HTML> <html> <head> <title>ProjectShare</title> <script src="http://localhost:8080/socket.io/socket.io.js"></script> <script src = "http://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js"></script> <script> //Make sure DOM is ready before mucking around. $(document).ready(function() { console.log('jQuery entered!'); var socket = io.connect('http://localhost:8080'); socket.emit('testEmit'); socket.on('testEmit2', function(data) { console.log('Emit recieved at browser.'); console.log(data); }); console.log('jQuery exit.'); }); </script> </head> <body> <ol> <li><a href="index.html">ProjectShare</a></li> <li><a href="guidelines.html">Guidelines</a></li> <li><a href="upload.html">Upload</a></li> <li> <form> <input type = "search" placeholder = "enter class code"/> <input type = "submit" value = "Go"/> </form> </li> </ol> <ol id = "documentList"> </ol> </body> </html>

    Read the article

  • Intel® Core™2 Duo Desktop Processor vs Intel® Core™ i3 Desktop Processor?

    - by metal gear solid
    Intel® Core™2 Duo Desktop Processor vs Intel® Core™ i3 Desktop Processor? Which CPU is better to buy ? Intel® Core™ i3-530 Processor (4M Cache, 2.93 GHz) (it supports DDR3 also) or Intel® Core™2 Duo Processor E7500 (3M Cache, 2.93 GHz, 1066 MHz FSB) (it supports DDR2 only ) Although I do not play games on my PC but I need good performance in Adobe Photoshop, Watching Full HD Movies. I need good performance in Multitasking. Along with any of these CPU I would purchase 2 GB x 2 stick of RAM. and I will use Windows 7. and I will use Microsoft VPC images also with MS Virtual PC.

    Read the article

  • How to Calculate TCP Socket Buffer Sizes for Data Guard Environments

    - by alejandro.vargas
    The MAA best practices contains an example of how to calculate the optimal TCP socket buffer sizes, that is quite important for very busy Data Guard environments, this document Formula to Calculate TCP Socket Buffer Sizes.pdf contains an example of using the instructions provided on the best practices document. In order to execute the calculation you need to know which is the band with or your network interface, usually will be 1Gb, on my example is a 10Gb network; and the round trip time, RTT, that is the time it takes for a packet to make a travel to the other end of the network and come back, on my example that was provided by the network administrator and was 3 ms (1000/seconds)

    Read the article

  • Kernel panic: "Machine check: processor context corrupt" after install

    - by Red
    I am new to Linux and I am having issues installing. I have tried multiple versions and all seem to give me the same issue. The LiveCD worked and I used it to install Ubuntu alongside Windows 7. Here's a few screen shots of what I get. I am currently trying to install most the most recent version of Ubuntu. System specs: x58 motherboard 12GB RAM Core i7 processor 2 Nvidia GTX 580 video cards in SLI configuration Thanks in advance and please feel free to simplify your answers as I am pretty new at this.

    Read the article

  • Issues with Dz77BH-55K Motherboard and i7 processor on 12.04

    - by Naveed
    I just built a computer with Intel's DZ77BH-55K motherboard with i7-3770 processor. On 12.04, 11.10, and 11.04 and Linux Mint 12, the computer has been really laggy. The graphics aren't working (choppy effects, bad resolution) and the keyboard and mouse inputs are even laggy and unreliable (skips keystrokes). I'm not sure what the problem is or what I can do to fix it. I tried sudo apt-get install mesa-utils but nothing changed. I've also messed around in the BIOS but no luck there either. Any ideas? Could it possibly be a hardware issue?

    Read the article

  • Running the Ubuntu Kernel and OS on custom processor

    - by xupv5
    This is hardly a theoretical question as many have done this, albeit there's very little information on the underlying processes. I'm developing a custom MIPS-based processor on which I would like to run ubuntu. I'm quite baffled as to what to do next after you've designed the instruction set and the computer architecture itself. I need to be able to run a kernel and OS but how does it all tie in? At the moment I'm researching into designing a compiler for the linux kernel to generate the appropriate assembly language. Is that a good way to go? What do I need to do after that?

    Read the article

  • How to establish a socket connection from iPhone to a Apache server and communicate via PHP?

    - by candoyo
    Hi, I am working on an iPhone game which is depended on a LAMP server. I want to create a "event" based system where the apache server sends an event to the iphone. For this, I am thinking of using "CFStreamCreatePairWithSocketToHost" to connect to port 80 of the apache server. I am able to successfully connect to the server and open a read and write stream via the iPhone, but I am not sure how to send data to the iphone using PHP running from the LAMP server to the iPhone. I think I can use fsockopen in php to open a socket connection and write data to that socket. I tired running this code $fp = fsockopen("tcp://localhost", 80, $errno, $errstr); if (!$fp) { echo "ERROR: $errno - $errstr<br />\n"; } else { echo"writing to socket "; fwrite($fp, "wwqeqweqw eqwe qwe \n"); //echo fread($fp, 26); fclose($fp); echo "done"; } But, I dont see anything being read on the iphone.. Any idea what's going on, or how to accomplish this? Thanks!

    Read the article

  • Why does async BeginReceiveFrom never time out on a raw socket?

    - by James Hugard
    Writing an asynchronous Ping using Raw Sockets in F#, to enable parallel requests using as few threads as possible. Not using "System.Net.NetworkInformation.Ping", because it appears to allocate one thread per request. Am also interested in using F# async workflows. The synchronous version below correctly times out when the target host does not exist/respond, but the asynchronous version hangs. Both work when the host does respond. Not sure if this is a .NET issue, or an F# one... Any ideas? (note: the process must run as Admin to allow Raw Socket access) This throws a timeout: let result = Ping.Ping ( IPAddress.Parse( "192.168.33.22" ), 1000 ) However, this hangs: let result = Ping.AsyncPing ( IPAddress.Parse( "192.168.33.22" ), 1000 ) |> Async.RunSynchronously Here's the code... module Ping open System open System.Net open System.Net.Sockets open System.Threading //---- ICMP Packet Classes type IcmpMessage (t : byte) = let mutable m_type = t let mutable m_code = 0uy let mutable m_checksum = 0us member this.Type with get() = m_type member this.Code with get() = m_code member this.Checksum = m_checksum abstract Bytes : byte array default this.Bytes with get() = [| m_type m_code byte(m_checksum) byte(m_checksum >>> 8) |] member this.GetChecksum() = let mutable sum = 0ul let bytes = this.Bytes let mutable i = 0 // Sum up uint16s while i < bytes.Length - 1 do sum <- sum + uint32(BitConverter.ToUInt16( bytes, i )) i <- i + 2 // Add in last byte, if an odd size buffer if i <> bytes.Length then sum <- sum + uint32(bytes.[i]) // Shuffle the bits sum <- (sum >>> 16) + (sum &&& 0xFFFFul) sum <- sum + (sum >>> 16) sum <- ~~~sum uint16(sum) member this.UpdateChecksum() = m_checksum <- this.GetChecksum() type InformationMessage (t : byte) = inherit IcmpMessage(t) let mutable m_identifier = 0us let mutable m_sequenceNumber = 0us member this.Identifier = m_identifier member this.SequenceNumber = m_sequenceNumber override this.Bytes with get() = Array.append (base.Bytes) [| byte(m_identifier) byte(m_identifier >>> 8) byte(m_sequenceNumber) byte(m_sequenceNumber >>> 8) |] type EchoMessage() = inherit InformationMessage( 8uy ) let mutable m_data = Array.create 32 32uy do base.UpdateChecksum() member this.Data with get() = m_data and set(d) = m_data <- d this.UpdateChecksum() override this.Bytes with get() = Array.append (base.Bytes) (this.Data) //---- Synchronous Ping let Ping (host : IPAddress, timeout : int ) = let mutable ep = new IPEndPoint( host, 0 ) let socket = new Socket( AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.Icmp ) socket.SetSocketOption( SocketOptionLevel.Socket, SocketOptionName.SendTimeout, timeout ) socket.SetSocketOption( SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout, timeout ) let packet = EchoMessage() let mutable buffer = packet.Bytes try if socket.SendTo( buffer, ep ) <= 0 then raise (SocketException()) buffer <- Array.create (buffer.Length + 20) 0uy let mutable epr = ep :> EndPoint if socket.ReceiveFrom( buffer, &epr ) <= 0 then raise (SocketException()) finally socket.Close() buffer //---- Entensions to the F# Async class to allow up to 5 paramters (not just 3) type Async with static member FromBeginEnd(arg1,arg2,arg3,arg4,beginAction,endAction,?cancelAction): Async<'T> = Async.FromBeginEnd((fun (iar,state) -> beginAction(arg1,arg2,arg3,arg4,iar,state)), endAction, ?cancelAction=cancelAction) static member FromBeginEnd(arg1,arg2,arg3,arg4,arg5,beginAction,endAction,?cancelAction): Async<'T> = Async.FromBeginEnd((fun (iar,state) -> beginAction(arg1,arg2,arg3,arg4,arg5,iar,state)), endAction, ?cancelAction=cancelAction) //---- Extensions to the Socket class to provide async SendTo and ReceiveFrom type System.Net.Sockets.Socket with member this.AsyncSendTo( buffer, offset, size, socketFlags, remoteEP ) = Async.FromBeginEnd( buffer, offset, size, socketFlags, remoteEP, this.BeginSendTo, this.EndSendTo ) member this.AsyncReceiveFrom( buffer, offset, size, socketFlags, remoteEP ) = Async.FromBeginEnd( buffer, offset, size, socketFlags, remoteEP, this.BeginReceiveFrom, (fun asyncResult -> this.EndReceiveFrom(asyncResult, remoteEP) ) ) //---- Asynchronous Ping let AsyncPing (host : IPAddress, timeout : int ) = async { let ep = IPEndPoint( host, 0 ) use socket = new Socket( AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.Icmp ) socket.SetSocketOption( SocketOptionLevel.Socket, SocketOptionName.SendTimeout, timeout ) socket.SetSocketOption( SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout, timeout ) let packet = EchoMessage() let outbuffer = packet.Bytes try let! result = socket.AsyncSendTo( outbuffer, 0, outbuffer.Length, SocketFlags.None, ep ) if result <= 0 then raise (SocketException()) let epr = ref (ep :> EndPoint) let inbuffer = Array.create (outbuffer.Length + 256) 0uy let! result = socket.AsyncReceiveFrom( inbuffer, 0, inbuffer.Length, SocketFlags.None, epr ) if result <= 0 then raise (SocketException()) return inbuffer finally socket.Close() }

    Read the article

  • How to detect a timeout when using asynchronous Socket.BeginReceive?

    - by James Hugard
    Writing an asynchronous Ping using Raw Sockets in F#, to enable parallel requests using as few threads as possible. Not using "System.Net.NetworkInformation.Ping", because it appears to allocate one thread per request. Am also interested in using F# async workflows. The synchronous version below correctly times out when the target host does not exist/respond, but the asynchronous version hangs. Both work when the host does respond. Not sure if this is a .NET issue, or an F# one... Any ideas? (note: the process must run as Admin to allow Raw Socket access) This throws a timeout: let result = Ping.Ping ( IPAddress.Parse( "192.168.33.22" ), 1000 ) However, this hangs: let result = Ping.AsyncPing ( IPAddress.Parse( "192.168.33.22" ), 1000 ) |> Async.RunSynchronously Here's the code... module Ping open System open System.Net open System.Net.Sockets open System.Threading //---- ICMP Packet Classes type IcmpMessage (t : byte) = let mutable m_type = t let mutable m_code = 0uy let mutable m_checksum = 0us member this.Type with get() = m_type member this.Code with get() = m_code member this.Checksum = m_checksum abstract Bytes : byte array default this.Bytes with get() = [| m_type m_code byte(m_checksum) byte(m_checksum >>> 8) |] member this.GetChecksum() = let mutable sum = 0ul let bytes = this.Bytes let mutable i = 0 // Sum up uint16s while i < bytes.Length - 1 do sum <- sum + uint32(BitConverter.ToUInt16( bytes, i )) i <- i + 2 // Add in last byte, if an odd size buffer if i <> bytes.Length then sum <- sum + uint32(bytes.[i]) // Shuffle the bits sum <- (sum >>> 16) + (sum &&& 0xFFFFul) sum <- sum + (sum >>> 16) sum <- ~~~sum uint16(sum) member this.UpdateChecksum() = m_checksum <- this.GetChecksum() type InformationMessage (t : byte) = inherit IcmpMessage(t) let mutable m_identifier = 0us let mutable m_sequenceNumber = 0us member this.Identifier = m_identifier member this.SequenceNumber = m_sequenceNumber override this.Bytes with get() = Array.append (base.Bytes) [| byte(m_identifier) byte(m_identifier >>> 8) byte(m_sequenceNumber) byte(m_sequenceNumber >>> 8) |] type EchoMessage() = inherit InformationMessage( 8uy ) let mutable m_data = Array.create 32 32uy do base.UpdateChecksum() member this.Data with get() = m_data and set(d) = m_data <- d this.UpdateChecksum() override this.Bytes with get() = Array.append (base.Bytes) (this.Data) //---- Synchronous Ping let Ping (host : IPAddress, timeout : int ) = let mutable ep = new IPEndPoint( host, 0 ) let socket = new Socket( AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.Icmp ) socket.SetSocketOption( SocketOptionLevel.Socket, SocketOptionName.SendTimeout, timeout ) socket.SetSocketOption( SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout, timeout ) let packet = EchoMessage() let mutable buffer = packet.Bytes try if socket.SendTo( buffer, ep ) <= 0 then raise (SocketException()) buffer <- Array.create (buffer.Length + 20) 0uy let mutable epr = ep :> EndPoint if socket.ReceiveFrom( buffer, &epr ) <= 0 then raise (SocketException()) finally socket.Close() buffer //---- Entensions to the F# Async class to allow up to 5 paramters (not just 3) type Async with static member FromBeginEnd(arg1,arg2,arg3,arg4,beginAction,endAction,?cancelAction): Async<'T> = Async.FromBeginEnd((fun (iar,state) -> beginAction(arg1,arg2,arg3,arg4,iar,state)), endAction, ?cancelAction=cancelAction) static member FromBeginEnd(arg1,arg2,arg3,arg4,arg5,beginAction,endAction,?cancelAction): Async<'T> = Async.FromBeginEnd((fun (iar,state) -> beginAction(arg1,arg2,arg3,arg4,arg5,iar,state)), endAction, ?cancelAction=cancelAction) //---- Extensions to the Socket class to provide async SendTo and ReceiveFrom type System.Net.Sockets.Socket with member this.AsyncSendTo( buffer, offset, size, socketFlags, remoteEP ) = Async.FromBeginEnd( buffer, offset, size, socketFlags, remoteEP, this.BeginSendTo, this.EndSendTo ) member this.AsyncReceiveFrom( buffer, offset, size, socketFlags, remoteEP ) = Async.FromBeginEnd( buffer, offset, size, socketFlags, remoteEP, this.BeginReceiveFrom, (fun asyncResult -> this.EndReceiveFrom(asyncResult, remoteEP) ) ) //---- Asynchronous Ping let AsyncPing (host : IPAddress, timeout : int ) = async { let ep = IPEndPoint( host, 0 ) use socket = new Socket( AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.Icmp ) socket.SetSocketOption( SocketOptionLevel.Socket, SocketOptionName.SendTimeout, timeout ) socket.SetSocketOption( SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout, timeout ) let packet = EchoMessage() let outbuffer = packet.Bytes try let! result = socket.AsyncSendTo( outbuffer, 0, outbuffer.Length, SocketFlags.None, ep ) if result <= 0 then raise (SocketException()) let epr = ref (ep :> EndPoint) let inbuffer = Array.create (outbuffer.Length + 256) 0uy let! result = socket.AsyncReceiveFrom( inbuffer, 0, inbuffer.Length, SocketFlags.None, epr ) if result <= 0 then raise (SocketException()) return inbuffer finally socket.Close() }

    Read the article

  • How to recover gracefully from a C# udp socket exception

    - by Gearoid Murphy
    Context: I'm porting a linux perl app to C#, the server listens on a udp port and maintains multiple concurrent dialogs with remote clients via a single udp socket. During testing, I send out high volumes of packets to the udp server, randomly restarting the clients to observe the server registering the new connections. The problem is this: when I kill a udp client, there may still be data on the server destined for that client. When the server tries to send this data, it gets an icmp "no service available" message back and consequently an exception occurs on the socket. I cannot reuse this socket, when I try to associate a C# async handler with the socket, it complains about the exception, so I have to close and reopen the udp socket on the server port. Is this the only way around this problem?, surely there's some way of "fixing" the udp socket, as technically, UDP sockets shouldn't be aware of the status of a remote socket? Any help or pointers would be much appreciated. Thanks.

    Read the article

  • Can I close and reopen a socket?

    - by Roman
    I learned an example of usage of sockets. In this example a client sends a request to a server to open a socket and then the server (listening to a specific port) opens a socket and everything is fine, socket is "opened" from both sides (client and server). But it is still not clear to me how flexible is this stuff. For example, is it possible for the client to close an opened (from both ends) socket and to reopen it again (under condition that the server keeps the socket opened). Is it possible for the server to "know" that a socket was closed on the client side? Is it possible for the client to know that a socket was closed on the server side?

    Read the article

  • "Can´t open socket or connection refused" with .NET

    - by HoNgOuRu
    Im getting a connection refused when I try to send some data to my server app using netcat. server side: IPAddress ip; ip = Dns.GetHostEntry("localhost").AddressList[0]; IPEndPoint ipFinal = new IPEndPoint(ip, 12345); Socket socket = new Socket(AddressFamily.InterNetworkV6, SocketType.Stream, ProtocolType.Tcp); socket.Bind(ipFinal); socket.Listen(100); Socket handler = socket.Accept(); ------> it stops here......nothing happens

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 7 8 9 10 11 12 13 14 15 16 17 18  | Next Page >