+/* Required yet non-standard cmsg functions */
+#ifndef CMSG_ALIGN
+# define CMSG_ALIGN(len) (((len) + sizeof(intptr_t)-1) & ~(sizeof(intptr_t)-1))
+#endif
+#ifndef CMSG_SPACE
+# define CMSG_SPACE(len) (CMSG_ALIGN(sizeof(struct cmsghdr)) + CMSG_ALIGN(len))
+#endif
+#ifndef CMSG_LEN
+# define CMSG_LEN(len) (CMSG_ALIGN(sizeof(struct cmsghdr)) + (len))
+#endif