[Bug 2127] WriteFile fails on threaded applications

[Wine Bugs]

http://bugs.winehq.org/show_bug.cgi?id=2127

------- Additional Comments From [e-mail]  2005-03-10 05:52 -------
The error 5 is because you didn't request GENERIC_WRITE access. This is still a
bug in Wine, but a different one.

Also note that the mutex in your sample code is useless since you create a new
one  for every invocation of the function. Still, it shouldn't fail even without
a mutex.