Using if statements with std_msgs::String::ConstPtr

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I have a node that is getting action calls from another node. Once it gets the action, I want to call a specific function but the if statement doesn't ever return true.

How can I get an if statement to work with a std_msgs string?

void chattersCallback(const std_msgs::String::ConstPtr& msg)
{
  ROS_INFO("I heard: %s", msg->data.c_str());
  if ((msg->data.c_str()) == "Listen") {sendStopAction();}
}

The terminal shows

[ INFO] [1381550860.740367371]: I heard: Listen

But the If statement does not return true. There is another print statement in the sendStopAction() function