TCPiP betwenn QT-Server und Labview-Client communication

Hello all,.

IAM new in network programming with LabVIEW.

I have a problem of communication of data via the TCP/IP protocol. I created a simple Client.vi that connect to the QT C++ server. If the connection is established, Client.vi sent a simple string "Hello" to Qt-server.

the problem is: Qt-Server receives an empty string with size 0!

Client.VI

QT-Server

QT-feature receive data :

Help, please

Of a possible problem you have, is that you look for a size of qint16. I'm not familiar with QT or used in the syntax of C++, but the duration of LabVIEW is an int32 and so 4 bytes. LabVIEW Typecast also creates big endian data stream, which means that the length of the string will be-> LSB MSB ordered, do the first 3 bytes in the flow of a 0 byte, causing your routine determine that there are 0 bytes to read.

You have read 4 bytes for the length parameter, change the byte order for your local boutien, more likely to have to share the big endian to little endian number and think of it as the number of bytes to read for the string.

Tags: NI Software

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