/* ** (C) Copyright 1999 Gary King ** All Rights Reserved. ** http://GKing.Harvard.Edu, King@Harvard.Edu ** Department of Government, Harvard University ** ** Does file exist on disk? ** ** yes = exist("input.asc"); ** ** Input: filename = a string ** output: yes = 1 if file exists, 0 otherwise */ proc exist(filename); retp(not files(filename,0) $== 0); endp;