GreSetHandle

GreSetHandle stores a handle or variable in the device context.

This function is supported by the graphics engine.

Syntax

GreSetHandle(hdc, hHandle, iIndex, pInstance, lFunction);

Parameters

hdc (HDC) - input

Device context handle.

hHandle (ULONG) - input

Handle to be associated with hdc.

iIndex (ULONG) - input

Index value of the handle in the range 0-3.

For a normal device context, this is a reserved parameter.

pInstance (PVOID) - input

Pointer to instance data.

lFunction (ULONG) - input

High-order WORD=flags; low-order WORD=NGreSetHandle.

Return Code

fSuccess (BOOL) - returns

Return codes.

On completion, the handling routine must return BOOLEAN (fSuccess).

• TRUE Successful
• FALSE Error

Possible Errors Detected: When an error is detected, the graphics engine calls WinSetErrorInfo to post the condition. Reasons for failure of this function include:

• PMERR_HDC_BUSY
• PMERR_INV_HDC

Refer to the "Error Explanations" section of the Presentation Manager Programming Reference for further explanation.

Remarks

Up to four handles can be stored in a DC at one time. The presentation driver can only use this function for device contexts that it has created for its own use with GreOpenDC.

Sample Code

#define INCL_GRE_DCS
#include <os2.h>

HDC      hdc;        /*  Device context handle. */
ULONG    hHandle;    /*  Handle to be associated with hdc. */
ULONG    iIndex;     /*  Index value of the handle in the range 0-3. */
PVOID    pInstance;  /*  Pointer to instance data. */
ULONG    lFunction;  /*  High-order WORD=flags; low-order WORD=NGreSetHandle. */
BOOL     fSuccess;   /*  Return codes. */

fSuccess = GreSetHandle(hdc, hHandle, iIndex,
             pInstance, lFunction);