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| Allegro CL version 9.0 Unrevised from 8.2 to 9.0. 8.2 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.

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This page was not revised from the 8.2 page.
Created 2012.5.30.

|  | ToC | DocOverview | CGDoc | RelNotes | FAQ | Index | PermutedIndex
| Allegro CL version 9.0 Unrevised from 8.2 to 9.0. 8.2 version