hdc (HDC) - input

Device context handle.

flCancel (ULONG) - input

The value of this flag specifies whether this call cancels the area definition:

EA_DRAW

Draw the area. This flag is the default.
EA_CANCEL
Cancel the area definition. Otherwise, draw the area.
Note: When GreBeginArea is not called and EA_CANCEL is set, GreEndArea is valid but has no effect, thus allowing the handling routine to reset an area bracket to a known state when it has no knowledge of the actual current state.

pInstance (PVOID) - input

Pointer to instance data.

lFunction (ULONG) - input

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

rc (LONG) - returns

Return codes.

This function returns an integer (cHits) indicating, where appropriate, whether correlation hits were detected:

GPI_OK

Successful
GPI_HITS
Successful with correlation hit (returned by display drivers when the correlation flag is ON, and a hit is detected) on any part of the interior, regardless of mix
GPI_ERROR
Error
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_BASE_ERROR PMERR_BITMAP_NOT_SELECTED
PMERR_COORDINATE_OVERFLOW
PMERR_DEV_FUNC_NOT_INSTALLED
PMERR_EXCEEDS_MAX_SEG_LENGTH
PMERR_HDC_BUSY
PMERR_HRGN_BUSY
PMERR_HUGE_FONTS_NOT_SUPPORTED
PMERR_INSUFFICIENT_MEMORY
PMERR_INV_AREA_CONTROL
PMERR_INV_BACKGROUND_COL_ATTR
PMERR_INV_BACKGROUND_MIX_ATTR
PMERR_INV_CHAR_DIRECTION_ATTR
PMERR_INV_CHAR_MODE_ATTR
PMERR_INV_CODEPAGE
PMERR_INV_COLOR_ATTR
PMERR_INV_COLOR_DATA
PMERR_INV_COLOR_INDEX
PMERR_INV_COORD_SPACE
PMERR_INV_COORDINATE
PMERR_INV_HDC
PMERR_INV_HRGN
PMERR_INV_IN_AREA
PMERR_INV_IN_PATH
PMERR_INV_LENGTH_OR_COUNT
PMERR_INV_LINE_TYPE_ATTR
PMERR_INV_MIX_ATTR
PMERR_INV_PATTERN_REF_PT_ATTR
PMERR_INV_PATTERN_SET_ATTR
PMERR_INV_PATTERN_SET_FONT
PMERR_INV_PICK_APERTURE_POSN
PMERR_INV_RECT
PMERR_INV_REGION_CONTROL
PMERR_NOT_IN_AREA
PMERR_PATH_LIMIT_EXCEEDED
PMERR_REGION_IS_CLIP_REGION.

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