wiasReadPropBin function (wiamdef.h)
The wiasReadPropBin function retrieves a binary-data property value from a WIA item.
Syntax
HRESULT wiasReadPropBin(
[in] BYTE *pWiasContext,
PROPID propid,
[out] BYTE **ppbVal,
[out, optional] BYTE **ppbValOld,
BOOL bMustExist
);
Parameters
[in] pWiasContext
Pointer to a WIA item context.
propid
Specifies the property identifier.
[out] ppbVal
Pointer to a memory location that receives the address of a buffer allocated by this function. Upon return, the buffer contains the property's binary data.
[out, optional] ppbValOld
Pointer to a memory location that receives the address of a buffer allocated by the minidriver. Upon return, the buffer contains the previous value of the property's binary data. If this information is not needed, this parameter can be set to NULL.
bMustExist
Indicates whether the property must exist. If set to TRUE, the property must exist; if set to FALSE, the property does not have to exist.
Return value
On success, the function returns S_OK.
If the function fails, it returns a standard COM error or one of the WIA error codes.
Remarks
This function allocates a buffer and stores its address in the ppbVal parameter. The minidriver must free the buffer by calling CoTaskMemFree.
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Desktop |
| Header | wiamdef.h (include Wiamdef.h) |
| Library | Wiaservc.lib |
| DLL | Wiaservc.dll |