diff --git a/src/osd/modules/file/posixfile.cpp b/src/osd/modules/file/posixfile.cpp
index 4f56a8432d4..764b148bc7d 100644
--- a/src/osd/modules/file/posixfile.cpp
+++ b/src/osd/modules/file/posixfile.cpp
@@ -37,6 +37,11 @@
 #endif
 #endif
 
+// Fix for MacOS compilation errors
+#if defined(__APPLE__) && !defined(_DARWIN_C_SOURCE)
+#define _DARWIN_C_SOURCE
+#endif
+
 // MAME headers
 #include "posixfile.h"
 #include "unicode.h"