Fix for CONC-455:
Fix for CONC-455:

Value of -1 was incorrect handled when using named pipes. Thanks
to Vladislav Vaintroub for providing this patch.

MariaDB/mariadb-connector-c,ottok/mariadb-connector-c,MariaDB/mariadb-connector-c,MariaDB/mariadb-connector-c,ottok/mariadb-connector-c,ottok/mariadb-connector-c