FUNCTION DirExist, directory

   ; This function is written to tell if a directory exists or not.
   ; It returns 0 if the directory does NOT exist, 1 otherwise.
   
   ; Save the current directory.
   
CD, Current=currentDirectory

   ; Use the Catch error handler to catch the case where we
   ; try to CD to a directory that doesn't exist.
   
Catch, error
IF (error NE 0) THEN BEGIN

      ; Directory must not exist. Return 0.
   
   RETURN, 0
ENDIF

   ; Try to CD to the directory. If it doesn't exist, an error occurs.
   
CD, directory

   ; Well, the directory MUST exist if we are here! Change back to
   ; the current directory and return a 1.
   
CD, currentDirectory
RETURN, 1
END