diff --git a/src/iothread.cpp b/src/iothread.cpp
index c62226aad..21017fbe7 100644
--- a/src/iothread.cpp
+++ b/src/iothread.cpp
@@ -6,6 +6,7 @@
 #include <pthread.h>
 #include <signal.h>
 #include <stdio.h>
+#include <string.h>
 #include <sys/select.h>
 #include <sys/time.h>
 #include <sys/types.h>