How do I Publish pcd files in my folder on a topic?

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So I have 100 pcd files. they look like this

VERSION .7 FIELDS x y z rgb SIZE 4 4 4 4 TYPE F F F U COUNT 1 1 1 1 WIDTH 38092 HEIGHT 1 VIEWPOINT 0 0 0 1 0 0 0 POINTS 38092 DATA ascii 224 0 681 2172952 229 0 662 2107159 ....

Now I want to publish these files one by one on a topic . How do I do that? I have gone through the pcl ros tutorials.They subscribe to a topic, do some processing inside the call back function and then they publish it on a topic.

What I want to do is just publish these pcd files on a topic

thanks