How to generate Gazebo using client?

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Right now I want to generate Gazebo simulation on a large number of .world files, one after another. One way of doing this is to write a shell script and basically kill the gazebo after one simulation and then run another one. I wonder if there is a better way to perform this task, like using a server to keep sending .world file to Gazebo and generating another simulation on differenct .world file without shutting down Gazebo? The reason I want to know how this could be done is that in another Robotic simulator webot, it's possible to do this, wonder if this can be done in Gazebo? Much appreciated for your help.