how to call publish/subscribe ?

[hpgundam]

There is code in hiredis README:
reply = redisCommand(context,"SUBSCRIBE foo");
and I tried to call subscribe command with following code:
redisReply *reply = redisClusterCommand(cc,"SUBSCRIBE test");
but reply is null and , cc->errstr is "parse command error"
I think this isn't the right way.
is there another function for publish/subscribe or they're not supported now ?