+const int ProcessIndexAny = 0;
+
+/** Options for read operations
+ *
+ * This is a set of flags managed with bitwise operators. Only the
+ * meaningful operations are defined: addition, conversions to/from
+ * integers are not allowed.
+ */
+class ReadOptions {
+ std::uint32_t value_;
+ constexpr explicit ReadOptions(std::uint32_t value) : value_(value) {}