unlink is not unix-specific, i don't know why people're saying that. see io.h. although you'll probably have to do something like
#define unlink _unlink
http://msdn.microsoft.com/en-us/library/1c3tczd6%28v=VS.100%29.aspx
http://msdn.microsoft.com/en-us/library/2da4hk1d%28v=VS.100%29.aspx