Problem with I/O files.

Hi.
I've got problem with writing signal values to file. I just can't write any data to text file. For example I wrote this code:

USE STD.TEXTIO.all;

architecture beh of io is
signal count : integer range 0 to 8 := 0;

begin

process(clk)
file outfile: text;
variable f_status: FILE_OPEN_STATUS;
variable buf: LINE;

begin

IF (CLK'EVENT and CLK = '1') THEN
file_open(f_status, outfile, "myfile.txt", write_mode);
WRITE (buf, integer'(count));
count <= count +1 ;
file_close(outfile);
end if;
end process;

end architecture beh;

I'm using quartus II, maybe I need to change something in my project settings...
Please help.

dziadek