--- a/Makefile	2017-08-26 11:47:02.981266309 +0200
+++ b/Makefile	2017-08-26 14:33:47.161600445 +0200
@@ -10,13 +10,13 @@
 all: $(TARGET)
 
 ttyrec: ttyrec.o io.o
-	$(CC) $(CFLAGS) -o ttyrec ttyrec.o io.o
+	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) -o ttyrec ttyrec.o io.o
 
 ttyplay: ttyplay.o io.o
-	$(CC) $(CFLAGS) -o ttyplay ttyplay.o io.o
+	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) -o ttyplay ttyplay.o io.o
 
 ttytime: ttytime.o io.o
-	$(CC) $(CFLAGS) -o ttytime ttytime.o io.o
+	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) -o ttytime ttytime.o io.o
 
 clean:
 	rm -f *.o $(TARGET) ttyrecord *~