+ ? ((ids)[2]-(ids)[1])+1 : (ids)[0] )
+
+#if 0 /* superseded by append/sort */
+ /** Insert an ID into an IDL.
+ * @param[in,out] ids The IDL to insert into.
+ * @param[in] id The ID to insert.
+ * @return 0 on success, -1 if the ID was already present in the IDL.
+ */
+int mdb_midl_insert( IDL ids, ID id );
+#endif
+
+ /** Allocate an IDL.
+ * Allocates memory for an IDL of a default size.
+ * @return IDL on success, NULL on failure.
+ */
+IDL mdb_midl_alloc();
+
+ /** Free an IDL.
+ * @param[in] ids The IDL to free.
+ */
+void mdb_midl_free(IDL ids);
+
+ /** Shrink an IDL.
+ * Return the IDL to the default size if it has grown larger.
+ * @param[in,out] idp Address of the IDL to shrink.
+ * @return 0 on no change, non-zero if shrunk.
+ */
+int mdb_midl_shrink(IDL *idp);
+
+ /** Append an ID onto an IDL.
+ * @param[in,out] idp Address of the IDL to append to.
+ * @param[in] id The ID to append.
+ * @return 0 on success, -1 if the IDL is too large.
+ */
+int mdb_midl_append( IDL *idp, ID id );
+
+ /** Append an IDL onto an IDL.
+ * @param[in,out] idp Address of the IDL to append to.
+ * @param[in] app The IDL to append.
+ * @return 0 on success, -1 if the IDL is too large.
+ */
+int mdb_midl_append_list( IDL *idp, IDL app );
+
+ /** Sort an IDL.
+ * @param[in,out] ids The IDL to sort.
+ */
+void mdb_midl_sort( IDL ids );
+
+ /** An ID2 is an ID/pointer pair.
+ */
+typedef struct ID2 {
+ ID mid; /**< The ID */
+ void *mptr; /**< The pointer */
+} ID2;
+
+ /** An ID2L is an ID2 List, a sorted array of ID2s.
+ * The first element's \b mid member is a count of how many actual
+ * elements are in the array. The \b mptr member of the first element is unused.
+ * The array is sorted in ascending order by \b mid.
+ */
+typedef ID2 *ID2L;
+
+ /** Search for an ID in an ID2L.
+ * @param[in] ids The ID2L to search.
+ * @param[in] id The ID to search for.
+ * @return The index of the first ID2 whose \b mid member is greater than or equal to \b id.
+ */
+unsigned mdb_mid2l_search( ID2L ids, ID id );
+
+
+ /** Insert an ID2 into a ID2L.
+ * @param[in,out] ids The ID2L to insert into.
+ * @param[in] id The ID2 to insert.
+ * @return 0 on success, -1 if the ID was already present in the ID2L.
+ */
+int mdb_mid2l_insert( ID2L ids, ID2 *id );
+
+/** @} */
+/** @} */