Introduction
  
   The socket extension implements a low-level interface to the socket
   communication functions based on the popular BSD sockets, providing the
   possibility to act as a socket server as well as a client.
  
  
   For a more generic client-side socket interface, see
   stream_socket_client(), 
   stream_socket_server(),
   fsockopen(), and
   pfsockopen().
  
  
   When using these functions, it is important to remember that while
   many of them have identical names to their C counterparts, they
   often have different declarations. Please be sure to read the
   descriptions to avoid confusion.
  
  
   Those unfamiliar with socket programming can find a lot
   of useful material in the appropriate Unix man pages, and there is a great
   deal of tutorial information on socket programming in C on the web, much
   of which can be applied, with slight modifications, to socket programming
   in PHP. The » Unix Socket
   FAQ might be a good start.
  
  Note: 
   
    This extension has been moved to the 
» PECL repository and is no longer bundled with 
PHP as of PHP 5.3.0.