terminal-io (original) (raw)

ANSI Common Lisp 21 Streams 21.2 Dictionary of Streams

Value Type:

a bidirectional stream.

Initial Value:

implementation-dependent, but it must be an open _stream_that is not a _generalized synonym stream_to an _I/O customization variables_but that might be a generalized synonym stream to the value of some I/O customization variable.

Description:

The value of *terminal-io*, called terminal I/O, is ordinarily a bidirectional stream that connects to the user's console. Typically, writing to this _stream_would cause the output to appear on a display screen, for example, and reading from the stream would accept input from a keyboard. It is intended that standard input functions such as read and read-char, when used with this stream, cause echoing of the input into the output side of the stream. The means by which this is accomplished are implementation-dependent.

The effect of changing the value of *terminal-io*, either by binding or assignment, is implementation-defined.

Examples:

(progn (prin1 'foo) (prin1 'bar terminal-io)) FOOBAR BAR (with-output-to-string (standard-output) (prin1 'foo) (prin1 'bar terminal-io)) BAR "FOO"

See Also:

*debug-io*,*error-output*,*query-io*,*standard-input*,*standard-output*,*trace-output*

Allegro CL Implementation Details:

None.