diff --git a/ext/socket/sockssocket.c b/ext/socket/sockssocket.c
index 1031812bef..f033f39b2e 100644
--- a/ext/socket/sockssocket.c
+++ b/ext/socket/sockssocket.c
@@ -30,7 +30,8 @@ socks_init(VALUE sock, VALUE host, VALUE port)
     static int init = 0;
 
     if (init == 0) {
-        SOCKSinit("ruby");
+        char progname[] = "ruby";
+        SOCKSinit(progname);
         init = 1;
     }