Publishing a Char Array

edit

Have you tried using C++ std::string data type? If that fits the use case, should be straightforward and simple. For example, I'm using this with boost::serialize

Publisher :

Advertise<topic type>("topic name", size)
Std_msgs::string msg;
Msg.data = std::string(char *)
Pub.publish(msg)

Subscriber :

void myCallback(const std:_msgs::string::constptr& msg) //prototype

//in the main : 
NodeHandle.subscribe(topic_Name,  buffer size, myCallback) //Create a subscriber object

Implement what you need in callback.