The CLOSE procedure closes an open file.

  Syntax:

             CLOSE( file_variable
                   ,[[disposition]]
                   ,[[user_action]]
                   ,[[ERROR := error_recovery]] )

             CLOSE( FILE_VARIABLE     := file_variable
                 [[,DISPOSITION       := disposition]]
                 [[,USER_ACTION       := user_action]]
                 [[,ERROR             := error_recovery]] )

  Except for the file variable parameter, all other parameters are
  optional.  If the nonpositional parameter names are not used, as
  in the first  syntax,  the  parameters  must  be  in  the  order
  specified.  If nonpositional parameter names are used, as in the
  second syntax, the parameters can be specified in any order.