PHP fread没有返回字符串

Question

    log_email("email to: " . $to . " at: " . $time);
}

function log_email($message){
    $dir = dirname(__FILE__);
    $filename = $dir . "/logs/email_log.txt";       
        echo $filename;

    if(is_readable($filename)){        
        $handle = fopen($filename, "w+");
        $contents = fread($handle, filesize($filename));
        fwrite($handle, $message . "
" . $contents);
        fclose($handle); 
    }else{
        echo 'The file is not readable.';
    }
}

The file has 777 access, the file contains some text. I get a warning up saying: Warning: fread(): Length parameter must be greater than 0 in ...

$contents variable ends up containing nothing? Any ideas? The directory must be correct because if i delete the file, my is_readable returns false.

Answer 1

You are truncating the file when you initially open it with this line.

$handle = fopen($filename, "w+");

So the size will be zero at that point triggering that warning.

You should probably do something like this:

function log_email($message){
    $dir = dirname(__FILE__);
    $filename = $dir . "/logs/email_log.txt";       
        echo $filename;

    if(is_readable($filename)){        
        // This will append to the file without destroying its contents
        $handle = fopen($filename, "a+"); 
        fwrite($handle, $message . "
");
        fclose($handle); 
    }else{
        echo 'The file is not readable.';
    }
}