(PHP 4 >= 4.1.0, PHP 5)
socket_sendto — Sends a message to a socket, whether it is connected or not
$socket
   , string $buf
   , int $len
   , int $flags
   , string $addr
   [, int $port = 0
  ] )
   The function socket_sendto() sends
   len bytes from buf
   through the socket socket to the
   port at the address addr.
  
socketA valid socket resource created using socket_create().
buf
       The sent data will be taken from buffer buf.
      
len
       len bytes from buf will be
       sent.
      
flags
       The value of flags can be any combination of 
       the following flags, joined with the binary OR (|)
       operator.
       
| MSG_OOB | Send OOB (out-of-band) data. | 
| MSG_EOR | Indicate a record mark. The sent data completes the record. | 
| MSG_EOF | Close the sender side of the socket and include an appropriate notification of this at the end of the sent data. The sent data completes the transaction. | 
| MSG_DONTROUTE | Bypass routing, use direct interface. | 
addrIP address of the remote host.
port
       port is the remote port number at which the data
       will be sent.
      
   socket_sendto() returns the number of bytes sent to the
   remote host, or FALSE if an error occurred.
  
Example #1 socket_sendto() Example
<?php
    $sock = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
    $msg = "Ping !";
    $len = strlen($msg);
    socket_sendto($sock, $msg, $len, 0, '127.0.0.1', 1223);
    socket_close($sock);
?>