diff --git a/lib/linebuffer.c b/lib/linebuffer.c
index 0d35fc0ce..67d0f1fd7 100644
--- a/lib/linebuffer.c
+++ b/lib/linebuffer.c
@@ -25,6 +25,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <sys/types.h>
 #include "linebuffer.h"
 #include "unlocked-io.h"