Sockets

Sockets
You are encouraged to solve this task according to the task description, using any language you may know.

For this exercise a program is open a socket to localhost on port 256 and send the message "hello socket world" before closing the socket. Catching any exceptions or errors is not required.

Ada

Library: GNAT RTL

<lang ada> with GNAT.Sockets; use GNAT.Sockets;

procedure SocketSend is

  procedure sendData (IP : String; Msg : String) is
     Client  : Socket_Type;
     Address : Sock_Addr_Type;
     Channel : Stream_Access; 
  begin
     Create_Socket (Client);
     Address.Addr := Inet_Addr(ip);
     Address.Port := 256;
     Connect_Socket (Client, Address);
     Channel := Stream (Client);
     String'Write (Channel, Msg);
     Close_Socket (Client);      
  end;

begin

  Initialize;
  sendData ("127.0.0.1","Hello Socket World");

end; </lang>

C

Works with: POSIX version .1-2001

Works with: gcc version 4.2.2

With little changes it could work on MS Windows (without Cygwin) too. But I don't know exactly how. I have tested it using the netcat -l -p 256.

<lang c>#include <stdio.h>

1. include <string.h>
2. include <sys/types.h>
3. include <sys/socket.h>
4. include <netdb.h>

char msg[] = "hello socket world";

int main() {

  int r, i, sock, len, slen;
  char *pm = msg;
  struct addrinfo hints, *res;
  
  memset(&hints, 0, sizeof(struct addrinfo));
  hints.ai_family = AF_UNSPEC;
  hints.ai_socktype = SOCK_STREAM;
  
  r = getaddrinfo("localhost", "256", &hints, &res);
  if ( r == 0 )
  {
      sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
      if ( sock >= 0 )
      {
          if ( connect(sock, res->ai_addr, res->ai_addrlen) >= 0 )
          {
              do
              {
                 len = strlen(pm);
                 slen = send(sock, pm, len, 0);
                 pm += slen;
              } while ( slen < len );
          }
          close(sock);
      }
      freeaddrinfo(res);
  }

}</lang>

C#

<lang csharp>using System; using System.IO; using System.Net.Sockets;

class Program {

   static void Main(string[] args) {
       TcpClient tcp = new TcpClient("localhost", 256);
       StreamWriter writer = new StreamWriter(tcp.GetStream());

       writer.Write("hello socket world");
       writer.Flush();

       tcp.Close();
   }

}</lang>

D

<lang d>module socket ; import std.stdio ; import std.socket ; version(Win32) {

 // For Win32 systems, need to link with ws2_32.lib. 
 pragma(lib, "ws2_32.lib") ; 

} void main() {

 auto socket = new Socket(AddressFamily.INET, SocketType.STREAM) ;
 socket.connect(new InternetAddress("localhost",256)) ;
 writefln(socket.send(cast(void[])"Hello socket world"), " bytes sent.") ;
 socket.close() ;

}</lang>

Haskell

import Network

main = withSocketsDo $ sendTo "localhost" (PortNumber $ toEnum 256) "hello socket world"

Icon

link cfunc
procedure main ()
   hello("localhost", 1024)
end
procedure hello (host, port)
   write(tconnect(host, port) | stop("unable to connect to", host, ":", port) ,  "Hello socket world")
end

IDL

 socket, unit, 'localhost',256,/get_lun  
 printf,unit,"Hello socket world" 
 close, unit 

"Well-known" port numbers (under 1024 -- such as 256) can also be specified by name (in this case 'RAP').

If there is no listener on this port, this will hang for a while before timing out.

Java

<lang java>import java.net.*; public class SocketSend {

 public static void main(String args[]) throws java.io.IOException {
   sendData("localhost", "Hello Socket World");
 }

 public static void sendData(String host, String msg) throws java.io.IOException{
   Socket sock = new Socket( host, 256 );
   sock.getOutputStream().write(msg.getBytes());
   sock.getOutputStream().flush();
   sock.close();
 }

}</lang> Encapsulating the Socket's OutputStream in a PrintStream (for data) or PrintWriter (for text) may be easier in more complex programs for their auto-flush abilities and their overloaded print and println methods. The write method from the original OutputStream will still be available.

OCaml

<lang ocaml>open Unix

let init_socket addr port =

 let inet_addr = (gethostbyname addr).h_addr_list.(0) in
 let sockaddr = ADDR_INET (inet_addr, port) in
 let sock = socket PF_INET SOCK_STREAM 0 in
 connect sock sockaddr;
 (* convert the file descriptor into high-level channels: *)
 let outchan = out_channel_of_descr sock in
 let inchan = in_channel_of_descr sock in
 (inchan, outchan)</lang>

<lang ocaml>let () =

 let ic, oc = init_socket "localhost" 256 in
 output_string oc "Hello Socket World";

</lang>

Perl

<lang perl>use Socket;

$host = gethostbyname('localhost'); $in = sockaddr_in(256, $host); $proto = getprotobyname('tcp'); socket(Socket_Handle, AF_INET, SOCK_STREAM, $proto); connect(Socket_Handle, $in); send(Socket_Handle, 'Hello socket world', 0, $in); close(Socket_Handle);</lang>

Object oriented version. <lang perl>use Socket::Class;

$sock = Socket::Class->new(

 'remote_port' => 256,

) || die Socket::Class->error; $sock->send('Hello socket world'); $sock->free;</lang>

Python

<lang python>import socket sock = socket.socket(AF_INET, SOCK_STREAM) sock.connect(("localhost", 256)) sock.sendall("hello socket world") sock.close()</lang>

Rhope

Works with: Rhope version alpha 1

Socket Send(0,0)
|:
    [New@Net Client["localhost",256]]Put String["hello socket world"]
:|

The connection is automatically closed when the object is freed.

Ruby

<lang ruby>require 'socket' sock = TCPSocket.open("localhost", 256) sock.write("hello socket world") sock.close</lang>

Seed7

$ include "seed7_05.s7i";
  include "socket.s7i";

const proc: main is func
  local
    var file: sock is STD_NULL;
  begin
    sock := openInetSocket(256);
    writeln(sock, "hello socket world");
    close(sock);
  end func;

Smalltalk

Works with: GNU Smalltalk

This is taken from here with few modification to fit the task better.

<lang smalltalk>PackageLoader fileInPackage: 'TCP'!

Object subclass: #HelloSocket

 instanceVariableNames: 'ss'
 classVariableNames: 
 poolDictionaries: 
 category: 'SimpleEcho'!

!HelloSocket class methodsFor: 'instance creation'!

port: anInteger

 | ses |
 ses := super new.
 ses init: anInteger.
 ^ses

!!

!HelloSocket methodsFor: 'instance initialization'!

init: anInteger

 ss := (TCP.ServerSocket port: anInteger).
 ^self

!!

!HelloSocket methodsFor: 'running'!

run

 | s |
 [
   ss waitForConnection.
   s := (ss accept).
   [self handleSocket: s] fork
 ] repeat

!!

!HelloSocket methodsFor: 'handling'!

handleSocket: s

   | msg |
   msg := 'hello socket world'.
   msg displayOn: s.
   (String with: (Character value: 10)) displayOn: s.
   s flush

!!

Smalltalk at: #helloServer put: (HelloSocket port: 2560).

helloServer run.</lang>

Tcl

<lang tcl>set io [socket localhost 256] puts $io "Hello socket world" close $io</lang>

Toka

 needs sockets
 
 #! A simple abstraction layer that makes writing trivial servers easy
 value| server.socket server.connection server.action |
 [ ( n- )   pBind to server.socket ] is server.setSocket
 [ ( - )    server.socket pAccept to server.connection ] is server.acceptConnection
 [ ( - )    server.connection pClose drop ] is server.closeConnection
 [ ( $- )   >r server.connection r> string.getLength pWrite drop ] is server.send
 [ ( an- )  server.connection -rot pRead drop ] is server.recieve
 [ ( qn- )  swap to server.action server.setSocket
   [ server.acceptConnection server.action invoke server.closeConnection TRUE ] whileTrue ] is server.start
 
 #! The actual server
 [ " hello socket world" server.send ] 256 server.start

UnixPipes

(echo "Hello World" | nc localhost 256 | exit 0)

UNIX Shell

Using the program netcat (nc)

echo "hello socket world" | netcat localhost 256