## Presentation Device Driver Reference for OS/2

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### GreEscape DEVESC_GETAPERTURE

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    Syntax
    Parameters
    Returns
    Glossary

Simulation support:

This function is mandatory for display drivers supporting software motion video. For other drivers, it is simulated by a handling routine in the graphics engine.

Description

GreEscape DEVESC_GETAPERTURE returns the size and physical address of the video aperture. For example, it would return "0A000h" and "64KB" for most Super VGA adapters. Care must be taken to determine if VGA emulation is active. If it is, a nonconflicting aperture is returned for the aperture address.

When multiple video adapters are present, this call returns the information for the adapter in use by the Presentation Manager for displaying the desktop.

    #define INCL_GRE_DEVICE

    #include <os2.h>

    HDC      hdc;         /*  Device context handle. */

    LONG     lCode;       /*  DEVESC_GETAPERTURE escape code. */

    LONG     lInCount;    /*  The handling routine should ignore this parameter. */

    PBYTE    pbInData;    /*  The handling routine should ignore this parameter. */

    PLONG    plOutCount;  /*  Number of bytes pointed to by pOutData. */

    PLONG    pbOutData;

    LONG     rc;          /*  Return Code. */

    rc = GreEscape(hdc, lCode, lInCount, pbInData,

           plOutCount, pbOutData);