0MQ/2.1 wire format compatibility implemented

- XS_PROTOCOL option added
- libxs ignores when unused flags are set to 1 (0MQ/2.1 bug)
- compatibility tests added

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/src/options.hpp b/src/options.hpp
index 3e47336..c1e4dda 100644
--- a/src/options.hpp
+++ b/src/options.hpp
@@ -92,6 +92,9 @@ namespace xs
         //  If 1, keepalives are to be sent periodically.
         int keepalive;
 
+        //  Version of wire protocol to use.
+        int protocol;
+
         //  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;