Comment 2 for bug 1388122

DBD::MySQL is linked against older libmysqlclient.16 (i.e. without .mylogin.cnf) support in every supported distribution, even the latest CentOS and Ubuntu releases. But yes, even if that wasn't the case, both libmysqlclient and DBD::MySQL need to be modified to support the --load-path option, which is not something we can control.

Which means the only option is to either 1) implement full support for .mylogin.cnf in innobackupex. Which is of course non-trivial. Percona Toolkit has a similar request, so you may want to check with Frank on this; or 2) implement https://blueprints.launchpad.net/percona-xtrabackup/+spec/rewrite-innobackupex-in-c :)