Basic question about stderr

[chaseratx via Digitalmars-d-learn]

I'm learning D and I have a basic question.

I'm trying to write stderr to a file using open() (rather than 
shell piping/redirection).  It works for stdout but doesn't seem 
to work with stderr.

http://pastebin.com/KgzR9wAF

stdout is written to the file, but stderr is not and outputs to 
the shell.  I'm not sure why.  I Googled but couldn't find an 
answer.  Any hints?