Was the original programmer of this code perhaps more familiar with another programming language which has a different meaning for unlink (such as releasing memory back to a pool)?
in reply to The strangest use of unlink I know of
A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James