diff --git a/libretroshare/src/chat/distantchat.cc b/libretroshare/src/chat/distantchat.cc
index 0f4dff401..aec5916e3 100644
--- a/libretroshare/src/chat/distantchat.cc
+++ b/libretroshare/src/chat/distantchat.cc
@@ -24,6 +24,8 @@
  */
 
 
+#include <unistd.h>
+
 #include "openssl/rand.h"
 #include "openssl/dh.h"
 #include "openssl/err.h"