crypt32::CryptMsgOpenToEncode

pub unsafe extern "system" fn CryptMsgOpenToEncode(dwMsgEncodingType: DWORD, dwFlags: DWORD, dwMsgType: DWORD, pvMsgEncodeInfo: *mut c_void, pszInnerContentObjID: LPSTR, pStreamInfo: PCMSG_STREAM_INFO) -> HCRYPTMSG