What is the state of a transaction if a timeout occurs after a call to tpcommit()? If the transaction timed out and the system knows that it was aborted, the system reports these events by setting tperrno(5) to TPEABORT. If the status of the transaction is unknown, the system sets the error code to TPETIME.

When the state of a transaction is in doubt, you must query the resource manager. First, verify whether or not any of the changes that were part of the transaction were applied. Then you can determine whether the transaction was committed or aborted.