(PHP 4 >= 4.1.0, PHP 5)
socket_getsockname — Queries the local side of the given socket which may either result in host/port or in a Unix filesystem path, dependent on its type
$socket
   , string &$addr
   [, int &$port
  ] )Note: socket_getsockname() should not be used with
AF_UNIXsockets created with socket_connect(). Only sockets created with socket_accept() or a primary server socket following a call to socket_bind() will return meaningful values.
socketA valid socket resource created with socket_create() or socket_accept().
addr
       If the given socket is of type AF_INET
       or AF_INET6, socket_getsockname()
       will return the local IP address in appropriate notation (e.g.
       127.0.0.1 or fe80::1) in the
       address parameter and, if the optional
       port parameter is present, also the associated port.
      
       If the given socket is of type AF_UNIX,
       socket_getsockname() will return the Unix filesystem
       path (e.g. /var/run/daemon.sock) in the
       address parameter.
      
portIf provided, this will hold the associated port.
   Returns TRUE on success or FALSE on failure. socket_getsockname() may also return
   FALSE if the socket type is not any of AF_INET,
   AF_INET6, or AF_UNIX, in which
   case the last socket error code is not updated.