diff --git a/src/include/86box/plat.h b/src/include/86box/plat.h
index 605482638..95a74f65f 100644
--- a/src/include/86box/plat.h
+++ b/src/include/86box/plat.h
@@ -36,7 +36,7 @@ extern int stricmp(const char* s1, const char* s2);
 extern int strnicmp(const char* s1, const char* s2, size_t n);
 #endif
 
-#if defined(UNIX) && defined(FREEBSD) || defined(__APPLE__)
+#if (defined(__unix__) || defined(__APPLE__)) && !defined(__linux__)
 /* FreeBSD has largefile by default. */
 # define fopen64        fopen
 # define fseeko64       fseeko