chmod is not working on php and I can not write a file!

Hi I want to write in a file with php, but I can not write anything. When I write this test function I got "Cannot change the mode of file deneme" error. How can use chmod and so that I can write into a file thanks for helping..

   <?php
        function file_write($filename, $flag, &$content) {
            if (file_exists($filename)) {
                if (!is_writable($filename)) {
                    if (!chmod($filename, 0666)) {
                         echo "Cannot change the mode of file ($filename)";
                         exit;
                    };
                }
            }
            if (!$fp = @fopen($filename, $flag)) {
                echo "Cannot open file ($filename)";
                exit;
            }
            if (fwrite($fp, $content) === FALSE) {
                echo "Cannot write to file ($filename)";
                exit;
            }
            if (!fclose($fp)) {
                echo "Cannot close file ($filename)";
                exit;
            }
        } 
$a="osman";  file_write("deneme", "w", &$a); 
?>开发者_如何学运维;

Refer to php manual and chmod() function http://php.net/manual/en/function.chmod.php as you need write permissions for that folder/file

I guess tha main thing is "The current user is the user under which PHP runs." Can you perform chmod on the file you've created via php script?

I am not sure if you looked into umask.