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.

1  –  File Variable

  The 'file_variable' is the name of the file variable  associated
  with the file that VSI Pascal is to close.

2  –  Disposition

  The 'disposition' is a value  that  indicates  what  VSI  Pascal
  should do with the file after you close the file.

  If SAVE is specified,  the  file  is  retained.   If  DELETE  is
  specified, the file is deleted.  If PRINT is specified, the file
  is printed on a line printer and is retained.   If  PRINT_DELETE
  is  specified,  the  file  is  deleted  after it is printed.  If
  SUBMIT is specified, the file is submitted to a queue or  placed
  in  a  background  process and is retained.  If SUBMIT_DELETE is
  specified, the file is deleted after being processed.

  SAVE is the default for external files.  DELETE is  the  default
  for internal files.

  The disposition  value  in  the  CLOSE  procedure  supersedes  a
  disposition value in the OPEN procedure.

3  –  User Action

  The 'user_action' is a routine name that  VSI  Pascal  calls  to
  close  the file.  You can use a user-action routine to close the
  file using environment-specific capabilities.

4  –  Error Recovery

  The 'error_recovery' specifies the action  to  be  taken  if  an
  error occurs during execution of the routine.  By default, after
  the first error, the error message is printed and  execution  is
  stopped.

  Execution of the CLOSE procedure causes the system to close  the
  file  and,  if the file is internal, to delete it.  Each file is
  automatically closed when control passes from the block in which
  it is declared.

  You cannot close  a  file  that  has  not  been  opened  (either
  explicitly  by  the OPEN procedure, or implicitly by the EXTEND,
  RESET, or REWRITE procedure).  If you attempt to  close  a  file
  that was never opened, an error occurs.

  The  file  can  be  in  any  mode  (inspection,  generation,  or
  undefined)  before  the CLOSE procedure is called.  Execution of
  CLOSE sets the mode to undefined.