php fwrite()

[Jörg]

Hallo,

Kann mir einer sagen, was ich hier falsch mache?

function loggen($var,$file = '2log.txt')
{
    $fp = fopen($file,'a+');
    fwrite($fp,$var."\r\n");
    fclose($fp);
}

loggen("Test");

// ergibt: PHP Fatal error:  Uncaught TypeError: fwrite(): Argument #1 ($stream) must be of type resource, bool given in...

Jörg