// wiamdef.h
HRESULT wiasReadPropStr(
[in] BYTE *pWiasContext,
PROPID propid,
[out] BSTR *pbstr,
[out, optional] BSTR *pbstrOld,
BOOL bMustExist
);
View the official Windows Driver Kit DDI referenceNo description available.
The wiasReadPropStr function retrieves a string property value from a WIA item.
pWiasContext [in]Pointer to a WIA item context.
propidSpecifies the property identifier.
pbstr [out]Pointer to a memory location that receives the first byte of the property's string value.
pbstrOld [out, optional]Pointer to a memory location that receives the first byte of the property's previous value. If this information is not needed, set this parameter to NULL.
bMustExistIndicates whether the property must exist. If set to TRUE, the property must exist; if set to FALSE, the property does not have to exist.
On success, the function returns S_OK. If the function fails, it returns a standard COM error or one of the WIA_ERROR_XXX errors (described in the Microsoft Windows SDK documentation).
When the minidriver has completed using the string it received from this function, it must deallocate the memory used for the string.