Any of the four upright supports of a bedstead:the best solution in the nineteenth-century home was to drape mosquito netting over the bedposts...
Jorge's room looked like a miniature log cabin; the walls, floor and ceiling were all made to look like wooden logs, as did the bedposts that supported the bed on the far right side.
Inside they found him sitting at the small wooden desk in the corner, his hat hung on one of the four bedposts and jacket thrown on the foot of his bed; the perfect picture of a cowboy.
He stood and tied one end of the long line of sheets to one of the four sturdy bedposts and flung the long line out the window.
Phrases
between you and me and the bedpost (or the gatepost or the wall)