diff --git a/opm/simulators/flow/Main.cpp b/opm/simulators/flow/Main.cpp
index 9ed9ccd0d..a90aacd78 100644
--- a/opm/simulators/flow/Main.cpp
+++ b/opm/simulators/flow/Main.cpp
@@ -45,16 +45,11 @@
 #endif
 
 #include <iostream>
+// NOTE: There is no C++ header replacement for these C posix headers (as of C++17)
 #include <fcntl.h>  // for open()
 #include <unistd.h> // for dup2(), close()
 
 #include <iostream>
-#include <fcntl.h>  // for open()
-#include <unistd.h> // for dup2(), close()
-
-#include <iostream>
-#include <fcntl.h>  // for open()
-#include <unistd.h> // for dup2(), close()
 
 namespace Opm {