hdc (HDC) - input

Device context handle.

ulSize (ULONG) - input

Size in bytes required for pBuffer.

Can be specified as 0. In this case, the function returns the size of the transform data:

ulSize=GreSaveXformData (hdc, 0, 0);     /* Find out how large the buffer must be, */
GreSaveXformData (hdc, ulSize, pBuffer); /* then save the transform state.         */

pInstance (PVOID) - input

Pointer to instance data.

lFunction (ULONG) - input

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

rc (ULONG) - returns

Return codes.

When called with ulSize specified as 0, it returns the size of the buffer required to save the transform state. Otherwise, it returns GPI_OK to indicate a successful completion. In either case, GPI_ERROR is returned to indicate failure.

Possible Errors Detected: When an error is detected, the handling routine must call WinSetErrorInfo to post the condition. Error codes for conditions that the handling routine is expected to check include:

PMERR_HDC_BUSY PMERR_INV_HDC
PMERR_INV_LENGTH_OR_COUNT

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