1 files changed, 5 insertions, 0 deletions
diff --git a/src/options.hpp b/src/options.hpp
index d8847f5..4689522 100644
--- a/src/options.hpp
+++ b/src/options.hpp
@@ -78,6 +78,11 @@ namespace zmq
         int rcvtimeo;
         int sndtimeo;
 
+        //  If 1, indicates the use of IPv4 sockets only, it will not be
+        //  possible to communicate with IPv6-only hosts. If 0, the socket can
+        //  connect to and accept connections from both IPv4 and IPv6 hosts.
+        int ipv4only;
+
         //  If true, session reads all the pending messages from the pipe and
         //  sends them to the network when socket is closed.
         bool delay_on_close;