Download files to local computer

[tanyali]

using php5, I download files :

******** downloadfile.php
$fileContent = @mysql_result($result1,$i,"gdata");

$ourFileName = "$gribname";
$ourFileHandle = fopen($ourFileName, 'w') or die("can't open file");
fwrite($ourFileHandle, $fileContent);
fflush($ourFileHandle);
fclose($ourFileHandle);
*********

but the file downloaded to the same directory with this downloadfile.php page,
how to specify a directory for the files downloaded ??
and all these files go to the computer in which the php pages in, how to download files to local computer and download them to a certain directory specified by user.

many thanks.
Tanya