As the title suggests, I have these walls and I want to erect a permanent tall fence between them. I can only attach to the walls, not the floor

I want to build hit and miss fencing because it's far better for wind, but I can't think of the best way to do that if the face of the fence has to be against one of the walls and therefore the post can't be directly attached to the wall. If I build the fence, then attach through the post to the wall, would that cause any issues with damp, it being against the wall permanently? It's covered so doesn't get wet.
In case anyone isn't sure what I mean, this is hit and miss fencing.
