diff --git a/dmesg.c b/dmesg.c
index e57f607..94e80ca 100644
--- a/dmesg.c
+++ b/dmesg.c
@@ -8,6 +8,14 @@
 #define KLOG_BUF_SHIFT	17	/* CONFIG_LOG_BUF_SHIFT from our kernel */
 #define KLOG_BUF_LEN	(1 << KLOG_BUF_SHIFT)
 
+// From Android sys/klog.h
+#ifndef KLOG_READ_ALL
+#define KLOG_READ_ALL   3
+#endif
+#ifndef KLOG_READ_CLEAR
+#define KLOG_READ_CLEAR 4
+#endif
+
 int dmesg_main(int argc, char **argv)
 {
     char buffer[KLOG_BUF_LEN + 1];