diff --git a/pymlac/make_ptr.c b/pymlac/make_ptr.c
new file mode 100644
index 0000000..1b24215
--- /dev/null
+++ b/pymlac/make_ptr.c
@@ -0,0 +1,19 @@
+/*
+ * Simple program to write a test PTR file.
+ */
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+int
+main(void)
+{
+    int fd = open("test.ptr", O_WRONLY|O_CREAT);
+
+    write(fd, "\0\1\2", 3);
+
+    close(fd);
+
+    return 0;
+}