gistfile1.txt

	/**
	 * Check the responsiveness of a tcp/ip daemon
	 * @return (bool) true when $host:$post responds within $float_timeout seconds, else (bool) false
	 */
	function check_tcp_responsiveness( $host, $port, $float_timeout ) {
		if ( function_exists( 'apc_store' ) ) {
			$use_apc = true;
			$apc_key = "{$host}{$port}";
			$apc_ttl = 10;
		} else {
			$use_apc = false;
		}

		if ( $use_apc ) {
			$cached_value = apc_fetch( $apc_key );
			switch ( $cached_value ) {
				case 'up':
					$this->tcp_responsive = 'true';
					return true;
				case 'down':
					$this->tcp_responsive = 'false';
					return false;
			}
		}

		$socket = @ fsockopen( $host, $port, $errno, $errstr, $float_timeout );
		if ( $socket === false ) {
			if ( $use_apc )
				apc_store( $apc_key, 'down', $apc_ttl );
			return "[ > $float_timeout ] ($errno) '$errstr'";
		}

		fclose( $socket );

		if ( $use_apc )
			apc_store( $apc_key, 'up', $apc_ttl );

		return true;
	}