Description
bool 
socket_getpeername ( resource socket, string &addr [, int &port] )
     If the given socket is of type AF_INET
     or AF_INET6, socket_getpeername() 
     will return the peers (remote) 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_getpeername() will return the Unix filesystem
     path (e.g. /var/run/daemon.sock) in the
     address parameter.
    
Note: 
      socket_getpeername() should not be used with
      AF_UNIX sockets created with socket_accept().
      Only sockets created with socket_connect() or a primary
      server socket following a call to socket_bind() will return
      meaningful values.
     
     Returns TRUE on success or FALSE on failure. socket_getpeername() 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.
    
     See also
     socket_getsockname(),
     socket_last_error() and
     socket_strerror().