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Write data to remote host over TCP/IP



    write(t,data) sends the N-dimensional matrix, data, to the remote host specified by the TCP/IP client t, and sends it as the data type of data. The function suspends MATLAB® execution until the specified values are written to the remote host.

    write(t,data,datatype) sends data in the form specified by datatype, regardless of the format in the matrix of data.


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    Create a TCP/IP client connection called t, connecting to a TCP/IP echo server with port 4000. To do so, you must have an echotcpip server running on port 4000.

    t = tcpclient("localhost",4000)
    t = 
      tcpclient with properties:
                  Address: 'localhost'
                     Port: 4000
        NumBytesAvailable: 0
      Show all properties, functions

    The write function synchronously writes data to the remote host connected to t. First specify the data and then write the data. The function suspends MATLAB execution until the specified number of values is written to the remote host.

    Assign 10 bytes of uint8 data to the variable data.

    data = uint8(1:10)
    data = 1×10 uint8 row vector
        1    2    3    4    5    6    7    8    9   10

    View the data.

    whos data
      Name      Size            Bytes  Class    Attributes
      data      1x10               10  uint8              

    Write data to the echo server.


    Confirm the success of the writing operation by viewing the NumBytesAvailable property.

    ans = 10

    Since the client is connected to an echo server, the data you write to the server is returned to the client. Read all the bytes of data available.

    ans = 1×10 uint8 row vector
        1    2    3    4    5    6    7    8    9   10

    Using the read function with no arguments reads all available bytes of data from t connected to the remote host and returns the data. The number of values read is determined by the NumBytesAvailable property, which is the number of bytes available in the input buffer.

    Close the connection between the TCP/IP client and the remote host by clearing the object. Turn off the echotcpip server.

    clear t

    Input Arguments

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    TCP/IP client, specified as a tcpclient object.

    Example: write(t,data) writes to the TCP/IP client t.

    Numeric or ASCII data, specified as a row (1-by-N) or column (N-by-1) vector of numeric values or as a character vector or string scalar of text. For all numeric datatype types, data is a row vector of values.

    Example: write(t,1:5) writes the values [1,2,3,4,5].

    Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | char | string

    Size and format of each value, specified as a character vector or string. datatype determines the number of bytes to write for each value and the interpretation of those bytes as a MATLAB data type.

    If you do not specify a datatype, the function sends data as the data type of data.

    Example: write(t,1:5,"double") writes the values [1,2,3,4,5] as double data.

    Data Types: char | string

    Extended Capabilities

    C/C++ Code Generation
    Generate C and C++ code using MATLAB® Coder™.

    Version History

    Introduced in R2014b