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readline

Read line of ASCII string data sent to TCP/IP server

Since R2021a

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    Syntax

    data = readline(t)

    Description

    data = readline(t) reads ASCII data sent to the TCP/IP server t from the client connected to it until the first occurrence of the terminator and returns data as a string without the terminator. If the function is unable to return any data within the period specified by the Timeout property of t, it returns data as a 0-by-0 double []. The function suspends MATLAB® execution until it reaches a terminator or a timeout occurs.

    example

    Examples

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    Open Live Script

    Create a TCP/IP server that listens for connections at localhost and port 4000.

    server = tcpserver("localhost",4000)
    server = 
  TCPServer with properties:

        ServerAddress: "127.0.0.1"
           ServerPort: 4000
            Connected: 0
        ClientAddress: ""
           ClientPort: []
    NumBytesAvailable: 0

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    Create a TCP/IP client to connect to your server object using tcpclient. You must specify the same IP address and port number you use to create server.

    client = tcpclient("localhost",4000)
    client = 
  tcpclient with properties:

              Address: 'localhost'
                 Port: 4000
    NumBytesAvailable: 0

  Show all properties, functions

    Check the default ASCII terminator for the server.

    server.Terminator
    ans = 
"LF"

    Set the terminators for both the server and client to "CR". The TCP/IP server and its connected client must have the same terminator.

    configureTerminator(server,"CR")
configureTerminator(client,"CR")

    Write a string of ASCII data to the client. The writeline function automatically appends the terminator to the data.

    writeline(client,"First message.")

    Write another string of ASCII data with the terminator automatically appended.

    writeline(client,"Second message.")

    Since the client is connected to the server, the data you send to the client is available to be read from the server. Read a string of ASCII data received by the server from the client. The readline function returns data until it reaches a terminator.

    readline(server)
    ans = 
"First message."

    Read a string of ASCII data again to return the second string.

    readline(server)
    ans = 
"Second message."

    Input Arguments

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    TCP/IP server, specified as a tcpserver object.

    Example: readline(t) reads ASCII data sent to the TCP/IP server t from the client connected to it.

    Version History

    Introduced in R2021a

    See Also

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