Man pages matching name tk_alloc3dborderfromobj in section 3tk:

Tk_Alloc3DBorderFromObj.3tk.en	debian 10 / tk8.6-doc
Tk_Alloc3DBorderFromObj.3tk.en	debian 11 / tk8.6-doc
Tk_Alloc3DBorderFromObj.3tk.en	debian 12 / tk8.6-doc