Move a certain distance (geometry_msg:Twist)

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Currently this is the code that I have, and I am able to get the robot moving by editing the linear x or angular z values (speed).

#include <ros/ros.h>
#include <geometry_msgs/Twist.h>

int main(int argc, char **argv)
{
ros::init(argc, argv, "move_pub");
ros::NodeHandle n;
ros::Publisher movement_pub = n.advertise<geometry_msgs::Twist>("mobile_base/commands/velocity",1); 
ros::Rate rate(10);

while (ros::ok()) 
{
    geometry_msgs::Twist move;
    //velocity controls
    move.linear.x = -0.1; //speed value m/s
    move.angular.z = 0;
    movement_pub.publish(move);

    ros::spinOnce();
    rate.sleep();
}
return 0;
}

Is there a time control in ROS? Whereby I can do something like while time <= 5s, publish linear x velocity of 0.2m/s. Thus, covering 1 meter. I am new to ROS and it is my first week into it. Im working on the TurtleBot 2.