Hi, I have a strange problem with input/output and threads using GambitC-4b22 (WinXP/MINGW). I tried to isolate it. It can be basically reproduced by running the following code in the interpreter: (define (main) (let ((t (make-thread (lambda () (display "\n\n\n hello world!\n\n\n") (force-output))))) (thread-start! t))) (main) Which does the expected thing: display the "hello world" message in the console. If I compile the above program to an executable it doesn't display the message anymore. In my real context, I am using a mutex and many threads are writing a trace to the console. In the compiled version I get no traces... What am I missing? Thank you, Francois Magnan