(PHP 4 >= 4.1.0, PHP 5)
socket_create_listen — Opens a socket on port to accept connections
$port
   [, int $backlog = 128
  ] )
   socket_create_listen() creates a new socket resource of
   type AF_INET listening on all
   local interfaces on the given port waiting for new connections.
  
This function is meant to ease the task of creating a new socket which only listens to accept new connections.
portThe port on which to listen on all interfaces.
backlog
       The backlog parameter defines the maximum length
       the queue of pending connections may grow to.
       SOMAXCONN may be passed as
       backlog parameter, see
       socket_listen() for more information.
      
   socket_create_listen() returns a new socket resource
   on success or FALSE on error. The error code can be retrieved with
   socket_last_error(). This code may be passed to
   socket_strerror() to get a textual explanation of the
   error.
  
Note:
If you want to create a socket which only listens on a certain interface you need to use socket_create(), socket_bind() and socket_listen().