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| Allegro CL version 10.1 Unrevised from 10.0 to 10.1. 10.0 version

## screenp

Arguments: object

Returns true if object is an instance of the `screen` class, and returns `nil` otherwise. This may be useful for determining whether the owner or parent of a window is the screen rather than a window, for example.

Currently there is only a single screen object, but a possible future enhancement would be the support of multiple monitors, where there is a screen object for each monitor. In that situation, calling screenp would be preferable to an expression such as `(eq my-stream (screen *system*))` (see screen and `*system*`).

See also windowp.

Copyright (c) 1998-2022, Franz Inc. Lafayette, CA., USA. All rights reserved.
This page was not revised from the 10.0 page.
Created 2019.8.20.

|  | ToC | DocOverview | CGDoc | RelNotes | FAQ | Index | PermutedIndex
| Allegro CL version 10.1 Unrevised from 10.0 to 10.1. 10.0 version