Use inline functions instead of macros to avoid problems in C++.
Inline functions respect scope, whereas macros don't.
Define umask in sys/stat.h, and mode_t in sys/types.h.
diff --git a/include/msvcrt/stdio.h b/include/msvcrt/stdio.h
index 91506ff..dee46c5 100644
--- a/include/msvcrt/stdio.h
+++ b/include/msvcrt/stdio.h
@@ -263,7 +263,10 @@
#define pclose _pclose
#define popen _popen
#define tempnam _tempnam
-#define unlink _unlink
+#ifndef MSVCRT_UNLINK_DEFINED
+static inline int unlink(const char* path) { return _unlink(path); }
+#define MSVCRT_UNLINK_DEFINED
+#endif
#define fgetwchar _fgetwchar
#define fputwchar _fputwchar
