diff --git a/libc/kernel/uapi/linux/if.h b/libc/kernel/uapi/linux/if.h
index 15de690..12967f7 100644
--- a/libc/kernel/uapi/linux/if.h
+++ b/libc/kernel/uapi/linux/if.h
@@ -27,6 +27,7 @@
 #define IFNAMSIZ 16
 #endif
 #define IFALIASZ 256
+#define ALTIFNAMSIZ 128
 #include <linux/hdlc/ioctl.h>
 #if __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO != 0 || __UAPI_DEF_IF_NET_DEVICE_FLAGS != 0
 enum net_device_flags {