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Transition Your Code to tcpclient Interface

The tcpip function, its object functions, and its properties will be removed. Use the tcpclient interface instead.

Removed Functionality

The LocalHost, LocalPort, and LocalPortMode properties will be removed.

The ValuesReceived and ValuesSent properties will be removed. You can calculate the number of values sent using the NumBytesAvailable property and the data type of the data available. For example, if the NumBytesAvailable is 20 bytes of uint32 data, the number of values sent is five since each uint32 value is four bytes.

The readasync and stopasync functions and the ReadAsyncMode and TransferStatus properties will be removed. The updated interface reads data asynchronously.

The BytesToOutput, InputBufferSize, and OutputBufferSize properties will be removed. Buffer sizes are automatically managed and sized as needed.

The OutputEmptyFcn property will be removed. You can set callback functions using configureCallback in the updated interface, but not for this property.

The RecordDetail, RecordMode, RecordName, and RecordStatus properties will be removed.

The TimerFcn and TimerPeriod properties will be removed. Use timer instead.

The Name, Type, ObjectVisibility, and Status properties will be removed.

Create a TCP/IP Client

These examples show how to create a TCP/IP client using the recommended functionality.

FunctionalityUse This Instead
t = tcpip("localhost",3030);
fopen(t)
t = tcpclient("localhost",3030);
t.ByteOrder = "big-endian";
t = tcpip("127.0.0.1",3030,"NetworkRole","client");
fopen(t)
t = tcpclient("127.0.0.1",3030);
t.ByteOrder = "big-endian";

Note

Since the default value of ByteOrder is bigEndian for tcpip objects and little-endian for tcpclient objects, you must set it using dot notation to make the property values match.

The fopen function is not available in the updated interface. The object creation function tcpclient both creates and connects the object.

For more information, see tcpclient.

Find Existing TCP/IP Client Connections

instrfind and instrfindall will be removed. Use tcpclientfind instead. (since R2024a)

Write and Read

These examples use an echo server to show how to perform a binary write and read, and how to write and read nonterminated string data, using the recommended functionality.

FunctionalityUse This Instead
echotcpip("on",3030)

% t is a tcpip object
fwrite(t,1:5);
data = fread(t,5)
data =

     1
     2
     3
     4
     5
echotcpip("on",3030)

% t is a tcpclient object
write(t,1:5,"uint8")
data = read(t,5)
data =

  1×5 uint8 row vector

   1   2   3   4   5
data = double(data)
data =

     1     2     3     4     5
echotcpip("on",3030)

% t is a tcpip object
fwrite(t,"hello","char")
length = 5;
data = fread(t,length,"char")
data =

   104
   101
   108
   108
   111
data = char(data)'
data =

    'hello'
echotcpip("on",3030)

% t is a tcpclient object
write(t,"hello","string");
length = 5;
data = read(t,length,"string")
data =

    "hello"

For more information, see write or read.

Read Terminated String

These examples show how to write and read terminated string data using the recommended functionality.

FunctionalityUse This Instead
echotcpip("on",3030)

% t is a tcpip object
t.Terminator = "CR";
fprintf(t,"hello")
data = fscanf(t)
data =

    'hello
     '
echotcpip("on",3030)

% t is a tcpclient object
configureTerminator(t,"CR");
writeline(t,"hello");
data = readline(t)
a = 

    "hello"
echotcpip("on",3030)

% t is a tcpip object
t.Terminator = "CR";
fprintf(t,"hello")
data = fgetl(t)
data =

    'hello'

fgetl reads until the specified terminator is reached and then discards the terminator.

echotcpip("on",3030)

% t is a tcpip object
t.Terminator = "CR";
fprintf(t,"hello")
data = fgets(t)
data =

    'hello
     '

fgets reads until the specified terminator is reached and then returns the terminator.

For more information, see writeline or readline.

Read and Parse String Data

This example shows how to read and parse string data using the recommended functionality.

FunctionalityUse This Instead
% t is a tcpip object
data = scanstr(t,';')
data =

  3×1 cell array

    {'a'}
    {'b'}
    {'c'}
% t is a tcpclient object
data = readline(t)
data = 

    "a;b;c"
data = strsplit(data,";")
data = 

  1×3 string array

    "a"    "b"    "c"

For more information, see readline.

Write and Read Back Data

This example shows how to write ASCII terminated data and read ASCII terminated data back using the recommended functionality.

FunctionalityUse This Instead
% t is a tcpip object
data = query(t,'ctrlcmd')
data =

    'success'
% t is a tcpclient object
data = writeread(t,"ctrlcmd")
data = 

    "success"

For more information, see writeread.

Write and Read Data with the Binary Block Protocol

This example shows how to write data with the IEEE standard binary block protocol using the recommended functionality.

FunctionalityUse This Instead
% t is a tcpip object
binblockwrite(t,1:5);
data = binblockread(t)
data =

     1
     2
     3
     4
     5
% t is a tcpclient object
writebinblock(t,1:5,"uint8");
data = readbinblock(t)
data =

     1     2     3     4     5

For more information, see writebinblock or readbinblock.

Flush Data from Memory

These examples show how to flush data from the buffer using the recommended functionality.

FunctionalityUse This Instead
% t is a tcpip object
flushinput(t)
% t is a tcpclient object
flush(t,"input")
% t is a tcpip object
flushoutput(t)
% t is a tcpclient object
flush(t,"output")
% t is a tcpip object
flushinput(t)
flushoutput(t)
% t is a tcpclient object
flush(t)

For more information, see flush.

Set Terminator

These examples show how to set the terminator using the recommended functionality.

FunctionalityUse This Instead
% t is a tcpip object
t.Terminator = "CR/LF";
% t is a tcpclient object
configureTerminator(t,"CR/LF")
% t is a tcpip object
t.Terminator = {"CR/LF" [10]};
% t is a tcpclient object
configureTerminator(t,"CR/LF",10)

For more information, see configureTerminator.

Set Up Callback Function

These examples show how to set up a callback function using the recommended functionality.

FunctionalityUse This Instead
% t is a tcpip object
t.BytesAvailableFcnCount = 5
t.BytesAvailableFcnMode = "byte"
t.BytesAvailableFcn = @mycallback

function mycallback(src,evt)
   data = fread(src,src.BytesAvailableFcnCount);
   disp(evt)
   disp(evt.Data)
end
    Type: 'BytesAvailable'
    Data: [1×1 struct]

    AbsTime: [2019 12 21 16 35 9.7032]
% t is a tcpclient object
configureCallback(t,"byte",5,@mycallback);

function mycallback(src,evt)
   data = read(src,src.BytesAvailableFcnCount);
   disp(evt)
end
  ByteAvailableInfo with properties:

    BytesAvailableFcnCount: 5
                   AbsTime: 21-Dec-2019 12:23:01
% t is a tcpip object
t.Terminator = "CR"
t.BytesAvailableFcnMode = "terminator"
t.BytesAvailableFcn = @mycallback

function mycallback(src,evt)
   data = fscanf(src);
   disp(evt)
   disp(evt.Data)
end
    Type: 'BytesAvailable'
    Data: [1×1 struct]

    AbsTime: [2019 12 21 16 35 9.7032]
% t is a tcpclient object
configureTerminator(t,"CR")
configureCallback(t,"terminator",@mycallback);

function mycallback(src,evt)
   data = readline(src);
   disp(evt)
end
  TerminatorAvailableInfo with properties:

                   AbsTime: 21-Dec-2019 12:23:01

For more information, see configureCallback.

Disconnect TCP/IP Client Connections

The fclose function is not available in the updated interface. To disconnect TCP/IP client connections, use clear or delete instead, depending upon whether you are working in a single workspace or multiple workspaces. For details, see the following examples on the tcpclient reference page:

See Also

Related Topics