<> = TCP = == Overview == '''TCP''' is a Dyalog cover class for Asynchronous TCP/IP Communication using the .Net [[https://msdn.microsoft.com/en-us/library/system.net.sockets.tcpclient%28v=vs.110%29.aspx|TcpClient]] object. It is using the methods '''!WriteAsync''' and '''!ReadAsync''' available with .Net 4.5 for asynchronous communication that will not block the calling thread during the communication process. It is used to requests data from an Internet resource using TCP (Transmission Control Protocol) over IP (Internet Protocol) like for home automation, data acquisition and process control. Real world programming of TCP/IP communication is difficult and this [[http://blog.stephencleary.com/2009/04/tcpip-net-sockets-faq.html|link]] is a good source of information. == Typical Usage == === Instantiating the class === {{{ tcp ← ⎕NEW TCP }}} === Connecting to a Remote Host === The TCP protocol establishes a connection with a remote endpoint and then uses that connection to send and receive data packets. TCP is responsible for ensuring that data packets are sent to the endpoint and assembled in the correct order when they arrive. The `Connect` method is used to establish this connection. In the class you can specify the ''buffer size'', the ''port time-out'', the ''switching delay'' as fields (see their individual comments in the class for more information). {{{ r ← tcp.Connect(ip port) ⍝ ip = IP Address where to send the bytes in characters ('192.168.1.1') or numbers (192 168 1 1) ⍝ port = Port Number to send the bytes (0 - 65535). ⍝ r[1] = 1 for Success, 0 for Failure ⍝ r[2] = Literal Error if Failure }}} === Sending the Data === The method `SendReceive` is used to send the data as numbers from 0 to 255 (bytes). The response contains the data received. To convert characters to bytes use `⎕UCS` to do the conversion. This method if successful will continuously reuse the same !TcpClient object. {{{ r ← {retries}tcp.SendReceive bytes ⍝ bytes = numbers from 0 to 255 ⍝ retries = Optional number of times to retry the communication if no data is received ⍝ r[1] = 1 for Success, 0 for Failure ⍝ r[2] = Response if Success, Literal Error if Failure }}} === Closing the Connection === The method `Close` is used to close the connection. {{{ r ← tcp.Close ⍝ r[1] = 1 for Success, 0 for Failure ⍝ r[2] = Literal Error if Failure }}} === Doing it all === The method `ConnectSendReceiveClose` will do all the methods necessary to Connect, Send, Receive and Close the socket as one operation. This method will use a new !TcpClient object each time. {{{ r ← {retries}tcp.ConnectSendReceiveClose(bytes ip port) ⍝ bytes = numbers from 0 to 255 ⍝ ip = IP Address where to send the bytes in characters ('192.168.1.1') or numbers (192 168 1 1) ⍝ port = Port Number to send the bytes (0 - 65535). ⍝ retries = Optional number of times to retry the communication if no data is received ⍝ r[1] = 1 for Success, 0 for Failure ⍝ r[2] = Literal Error if Failure }}} === How to install TCP in your workspace === 1. Download [[attachment:TCP.v1.0.txt]] 1. Do a Select all (Ctrl+A) and a copy (Ctrl+C). 1. In your workspace execute `)ed ○ TCP` 1. Paste (Ctrl+V) the text into the Dyalog editor 1. Press Escape and ')save' your workspace == Version Information == {{{ Version 1.0 January 2016, Pierre Gilbert }}} ||Original author: ||Pierre Gilbert || ||Responsible: ||PierreGilbert || ||Email: || <> || ---- See also: [[netCOM]] [[netUDP]] ---- CategoryDyalog - CategoryDyalogDotNet - CategoryDotNet