//------------------------------------------------------------>
// Locking is most efficient if we set all files to readonly
// except for the one we want to deal with, so this function
// will set all files in the filelist to either state.
//------------------------------------------------------------>
Define giDefault   for 0
Define giReadOnly  for 1

Procedure SetFileModes Global integer istate
   integer ifile

   Repeat
      get_attribute df_file_next_opened of ifile to ifile
      if ifile begin
         if (istate = giReadOnly) set_attribute df_file_mode of ifile to df_filemode_readonly
         else set_attribute df_file_mode of ifile to df_filemode_default
      end
   Until (ifile = 0)

End_Procedure