4.6.7.9 Closing a Stream

• close(X) closes the stream corresponding to X, where X should be a stream object created by open/[3,4], or a file specification passed to see/1 or tell/1. In the example:

            see(foo),
            ...
            close(foo)
  

  foo will be closed. However, in the example:

            open(foo, read, S),
            ...
            close(foo)
  

  an exception will be raised and foo will not be closed. See mpg-ref-close.

• told/0 closes the current output stream. The current output stream is then set to be user_output.
• seen/0 closes the current input stream. The current input stream is then set to be user_input.