diff --git a/mu/mu-cmd-server.c b/mu/mu-cmd-server.c
index 0209ef80..f9942852 100644
--- a/mu/mu-cmd-server.c
+++ b/mu/mu-cmd-server.c
@@ -22,7 +22,7 @@
 #include "config.h"
 #endif /*HAVE_CONFIG_H*/
 
-#define _BSD_SOURCE
+#define _GNU_SOURCE
 
 #include <stdlib.h>
 #include <stdio.h>