Databases
StackOverflow2013
Postsdbo
POClient cannot receive data - Exception with socket.async_receive in client
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POClient cannot receive data - Exception with socket.async_receive in client
    primarykey
    data
    text
    <p>I have a simple version of a client using boost asio. The client is suppose to receive a response from the server once it sends data. Here is the code of the client</p> <pre><code>void RunClient() { try { boost::asio::io_service io_service; boost::asio::ip::tcp::resolver resolver(io_service); boost::asio::ip::tcp::resolver::query query( "127.0.0.1", boost::lexical_cast&lt; std::string &gt;( 7777 )); //9100 boost::asio::ip::tcp::resolver::iterator endpoint_iterator = resolver.resolve(query); boost::asio::ip::tcp::socket socket(io_service); socket.async_receive(boost::asio::buffer(buf_client, 3000), 0, ClientReceiveEvent); boost::asio::connect(socket, endpoint_iterator); boost::system::error_code ignored_error; std::cout &lt;&lt; "Sending message \n"; boost::asio::write(socket, boost::asio::buffer("Data to send"), ignored_error); io_service.run(); } catch (std::exception &amp; ex) { std::cout &lt;&lt; "[" &lt;&lt; boost::this_thread::get_id()&lt;&lt; "] Exception: " &lt;&lt; ex.what() &lt;&lt; std::endl; } } </code></pre> <p>Here is my ClientReceiveEvent</p> <pre><code>void ClientReceiveEvent(const boost::system::error_code&amp; error, std::size_t bytes_transferred) { if(!error) { std::cout &lt;&lt; "Message: " &lt;&lt; buf_client.data() &lt;&lt; std::endl; } else { std::cout &lt;&lt; "Error occurred." &lt;&lt; error.message() &lt;&lt; std::endl; } } </code></pre> <p>I am getting an error from the above method for incoming data</p> <pre><code>Error occurred.The file handle supplied is not valid </code></pre> <p>Any suggestion what i am doing wrong in the client ?</p> <p><strong>Update:</strong></p> <p>I got the code working however I am confused as to why the statement</p> <pre><code>socket-&gt;async_receive(boost::asio::buffer(buf_client, 3000), 0, ClientReceiveEvent); </code></pre> <p>needs to be placed after connect. and why the statement</p> <pre><code>io_service-&gt;run(); </code></pre> <p>needs to be placed at the end. I thought this starts the asynch process.</p> <p>I also wanted to know how would i resend data to the server. I could send it once successfully. How do i resend the command again?</p> <p>The working code is:</p> <pre><code>boost::shared_ptr&lt; boost::asio::io_service &gt; io_service(new boost::asio::io_service); boost::shared_ptr&lt; boost::asio::ip::tcp::socket &gt; socket( new boost::asio::ip::tcp::socket( *io_service ) ); boost::asio::ip::tcp::resolver resolver(*io_service); boost::asio::ip::tcp::resolver::query query( "127.0.0.1", boost::lexical_cast&lt; std::string &gt;( 7777 )); //9100 boost::asio::ip::tcp::resolver::iterator endpoint_iterator = resolver.resolve(query); socket-&gt;connect(endpoint_iterator-&gt;endpoint()); socket-&gt;async_receive(boost::asio::buffer(buf_client, 3000), 0, ClientReceiveEvent); boost::system::error_code ignored_error; std::cout &lt;&lt; "Sending message \n"; boost::asio::write(*socket, boost::asio::buffer("some data"), ignored_error); io_service-&gt;run(); </code></pre>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USSam Miller
    1. USMistyD
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COEven though the `async_receive` will only execute after you've called run(), it might still require a connected socket at the time you call `async_receive`. Have you tried changing the order of `connect` and `async_receive`?
      singulars
      1. POClient cannot receive data - Exception with socket.async_receive in client
      1. USdhavenith
    2. COJust updated my post. It still does not work
      singulars
      1. POClient cannot receive data - Exception with socket.async_receive in client
      1. USMistyD
    3. COyour code still calls `async_receive` before `connect`. Internally, this may (I'm guessing here) post the internal socket handle to the sockets service object. If my guess is right, then the synchronous write should succeed and after that the async_receive should fail.
      singulars
      1. POClient cannot receive data - Exception with socket.async_receive in client
      1. USdhavenith
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload