TCP read bytes to read

Hello! I have a small question on ports TCP read palett in labview, im trying to send 1 bit from a server to a client. This works when I put 4 digital in the bytes to read TCP entry read client-side. But when I change the value to 1, as it should be efficiant, this work dosent. Any ideas?

Your number of bytes value is a number of I32 (32 bits, or 4 bytes), so you send 4 bytes followed by 1 byte for the boolean itself.   You can convert the number of bytes in an I8 to make a byte (but I wouldn't bother because the IP header information is the number of bytes, which means 1 to 4 bytes means little).

Tags: NI Software

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    azavarsky wrote:

    Hello

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    Concerning

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  • SocketConnection packets TCP 1 byte

    I encounter strange behavior when using SocketConnection. I use JDE 4.6.0 and you encounter the problem on a "Bold" 4.6.0.185 OS as well as the OS 4.6.0.216.

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            try {          writerStream.write( encodedBuffer );          writerStream.flush();        }        catch(IOException e)        {        }       }    }  } 
    

    I don't change any SocketStream options. Access to the file sending is correctly synchronized. Reading in the ConnectionThread is more sophisticated and actually consume the data.

    That's what I see on the network. Using another (Windows) client to connect to the server works properly, so this isn't a problem with the server.

    [email protected]: ~ #.

    signature ngrep w - q r the 76.110.XX host. XX and port 5222
    Interface: eth0 (85.10.193.64/255.255.255.224)
    filter: (ip or ip6) and (76.110.XX the host. XX and port 5222)

    T 76.110.XX. XX:55192-> 85.10.XX. XX:5222 [AP]

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    (...)

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    .

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    0

    T 76.110.XX. XX:55192-> 85.10.XX. XX:5222 [AP]
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    T 76.110.XX. XX:55192-> 85.10.XX. XX:5222 [AP]
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    T 85.10.XX. XX:5222-> 76.110.XX. XX:55192 [AP]
    http://EtheRx.Jabber.org/streams"xmlns =" jabber client: "from =" host.com"id ="59649 b 8"XML: lang ="en"version ="1.0">"

    T 85.10.XX. XX:5222-> 76.110.XX. XX:55192 [AP]
    arams:XML:ns:XMPP - tls ">arams:xml:ns:xmpp - sasl" >DIGEST-MD5PLAINANONYMOUSCRAM-MD5SHAREDSECRET JIVEhttp://jabber.org/features/compress "' >zlib <> xmlns ="http://jabber.org/features/iq-auth "/ >: features >

    (actually two bytes * here seem to Miss! There should be"<' and="">

    T 76.110.XX. XX:55192-> 85.10.XX. XX:5222 [AP]
    q

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    There

    OK, so I found the problem :-)

    My code is actually oversimplified, and I left out an important part. I was not using OutputStream but instead to use a derived class, that I would spend the OutputStream of the connection.openOutputStream call.

    The problem with my derived class was that she only substitute write (int data) and do not write (byte [] data).

    What happens in this case, it's that the default implementation calls OutputStream.write (byte [] data) write (int data) for each single byte.

    The fix was also replace write (byte [] data) and call the write method (byte [] data) of the original stream.

  • Reading TCP timeout

    I understand that other discussions on this topic are already, but I still have to find a solution among them.

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    Solved.

    Remove the end must be disabled to get rid of Reading TCP timeout.

  • Reading TCP does not detect the network closed conncetion error (66)

    Hi dear all,

    Instead of LAN I use WIFI to connect PC and mobile. Read all communications and write operations are performing ok. But the only problem I am facing is that once I disconnect the network from a mobile phone connection my labview TCP read operation does not detect it and only timesout at the specified interval. Although for Bluetooth connection network if I disconnect mobile then BT read detects it as network conncetion closed in error by peer (66).

    Can someone help me on this.

    Thank you & best regards

    Zdzislaw qureshi

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    Kim

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