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GreGetHandle

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Revision as of 03:26, 31 December 2019 by Martini (talk | contribs) (Created page with "GreGetHandle returns the handle or variable (stored in the DC corresponding to iIndex) previously set by GreSetHandle. This function is supported by the graphics engine. =...")
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GreGetHandle returns the handle or variable (stored in the DC corresponding to iIndex) previously set by GreSetHandle.

This function is supported by the graphics engine.

Syntax

GreGetHandle(hdc, iIndex, pInstance, lFunction);

Parameters

hdc (HDC) - input
Device context handle.
iIndex (ULONG) - input
Index value.
Index value of the returned handle in the range 0 - 3. A value of 1 can be used to get the associated AVIO presentation space handle.
pInstance (PVOID) - input
Pointer to instance data.
lFunction (ULONG) - input
High-order WORD=flags; low-order WORD=NGreGetHandle.

Return Code

rc (LONG) - returns
Return code.
On completion, the graphics engine returns the handle requested hHandle), or GPI_ALTERROR if an error occurs.
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.

Sample Code

#define INCL_GRE_DCS
#include <os2.h>

HDC      hdc;        /*  Device context handle. */
ULONG    iIndex;     /*  Index value. */
PVOID    pInstance;  /*  Pointer to instance data. */
ULONG    lFunction;  /*  High-order WORD=flags; low-order WORD=NGreGetHandle. */
LONG     rc;         /*  Return code. */

rc = GreGetHandle(hdc, iIndex, pInstance, lFunction);