Function xgboost_sys::XGBoosterGetAttrNames

pub unsafe extern "C" fn XGBoosterGetAttrNames(
    handle: BoosterHandle,
    out_len: *mut bst_ulong,
    out: *mut *mut *const c_char
) -> c_int

\brief Get the names of all attribute from Booster. \param handle handle \param out_len the argument to hold the output length \param out pointer to hold the output attribute stings \return 0 when success, -1 when failure happens