human-readable XA RECOVER

XA RECOVER prints data in binary, because that format — raw XIDs — is most useful for the transaction coordinator.

But occasionally, a human intervention is necessary. For this use case it would be convenient if XA RECOVER could return XID in some format that can be directly copied into XA COMMIT or XA ROLLBACK.

Also, mysql command line client has a --binary-as-hex option, but it does not work for XA RECOVER. It should be fixed, if possible.

MySQL has the command XA RECOVER CONVERT XID that returns the value of XID in hex. But it cannot be directly copied into XA COMMIT or XA ROLLBACK.