+/* Attempts to commit 'txn'. Returns the status of the commit operation, one
+ * of the following TXN_* constants:
+ *
+ * TXN_INCOMPLETE:
+ *
+ * The transaction is in progress, but not yet complete. The caller
+ * should call again later, after calling ovsdb_idl_run() to let the IDL
+ * do OVSDB protocol processing.
+ *
+ * TXN_UNCHANGED:
+ *
+ * The transaction is complete. (It didn't actually change the database,
+ * so the IDL didn't send any request to the database server.)
+ *
+ * TXN_ABORTED:
+ *
+ * The caller previously called ovsdb_idl_txn_abort().
+ *
+ * TXN_SUCCESS:
+ *
+ * The transaction was successful. The update made by the transaction
+ * (and possibly other changes made by other database clients) should
+ * already be visible in the IDL.
+ *
+ * TXN_TRY_AGAIN:
+ *
+ * The transaction failed for some transient reason, e.g. because a
+ * "verify" operation reported an inconsistency or due to a network
+ * problem. The caller should wait for a change to the database, then
+ * compose a new transaction, and commit the new transaction.
+ *
+ * Use the return value of ovsdb_idl_get_seqno() to wait for a change in
+ * the database. It is important to use its return value *before* the
+ * initial call to ovsdb_idl_txn_commit() as the baseline for this
+ * purpose, because the change that one should wait for can happen after
+ * the initial call but before the call that returns TXN_TRY_AGAIN, and
+ * using some other baseline value in that situation could cause an
+ * indefinite wait if the database rarely changes.
+ *
+ * TXN_NOT_LOCKED:
+ *
+ * The transaction failed because the IDL has been configured to require
+ * a database lock (with ovsdb_idl_set_lock()) but didn't get it yet or
+ * has already lost it.
+ *
+ * Committing a transaction rolls back all of the changes that it made to the
+ * IDL's copy of the database. If the transaction commits successfully, then
+ * the database server will send an update and, thus, the IDL will be updated
+ * with the committed changes. */