diff --git a/tools/zmq-keygen.cpp b/tools/zmq-keygen.cpp
index a4ee3648f..2d4ede2ca 100644
--- a/tools/zmq-keygen.cpp
+++ b/tools/zmq-keygen.cpp
@@ -36,7 +36,7 @@
   #include <zmq_utils.h>
 #endif
 
-int main (int argc, char *argv[])
+int main(int argc, char *argv[])
 {
 	int ret;
 	char public_key[41];