Local File (server side) output

[DigitHeads]

i need to open and write to a standard ascii file, but on the local C: drive, not on the server.

is there a way to use fopen to open a file from C:\directory\file.dat ?

the client machie is local (server side).

i have tried using c: in the filename, however it seems to just ignore it.

can i possibly copy the output to the local drive via php ?

my code is very simple:

$FileName="myfile.txt";
$handle=fopen($FileName,w);

this will open and let me output to the file on the server, however i need to either:
a) write directly to the users hard drive, or b) copy the data once i close the file.

Please HELP !!!

[AstroTeg]

Impossible.

You do understand the security risks involved if you could do this, right? Which is why you're not allowed to do this.

The user would have to upload the file. You modify it. And then allow the user to download the modified file.