diff --git a/unix/mpconfigport.h b/unix/mpconfigport.h
index a6bd98a7270e3d58c138acf6e6d3d31b7c43a4ec..e55eb2cec25ab5720d6c18e1c0446a8ab4921358 100644
--- a/unix/mpconfigport.h
+++ b/unix/mpconfigport.h
@@ -224,8 +224,6 @@ extern const struct _mp_obj_fun_builtin_t mp_builtin_open_obj;
     mp_obj_t keyboard_interrupt_obj; \
     void *mmap_region_head; \
 
-#define MICROPY_MPHALPORT_H "unix_mphal.h"
-
 // We need to provide a declaration/definition of alloca()
 #ifdef __FreeBSD__
 #include <stdlib.h>
diff --git a/unix/unix_mphal.h b/unix/mphalport.h
similarity index 98%
rename from unix/unix_mphal.h
rename to unix/mphalport.h
index 8961722db7f8d940a159fdc961e10536018ea5d3..98bbadbda57c828c0ee020845da9373ecca0d83a 100644
--- a/unix/unix_mphal.h
+++ b/unix/mphalport.h
@@ -23,6 +23,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+#include <unistd.h>
 
 #ifndef CHAR_CTRL_C
 #define CHAR_CTRL_C (3)