How to use "*.def" files in order to avoid cmd windows ?

[Vinod K Chandran]

Hi all,
I am just playing with some win api code in D. Well, so far so 
good. I've create a simple program which shows a message box. I 
know i can avoid the cmd window with "dmd -L/SUBSYSTEM:windows". 
But this https://wiki.dlang.org/D_for_Win32 says that a "*.def" 
file with these two lines
"EXETYPE NT
SUBSYSTEM WINDOWS "
can avoid the cmd window. I tried but no lick. I 'named the the 
def file "simple.def", since my programs name is also "simple". 
But no luck. Any help ?