The Berkeley DB database library (version 4.6) for C and C++
The Berkeley Database (Berkeley DB) is a programmatic toolkit that provides embedded database support for both traditional and client/server applications. The Berkeley DB includes B+tree, Extended Linear Hashing, Fixed and Variable-length record access methods, transactions, locking, logging, shared memory caching, and database recovery. The Berkeley DB supports C, C++, Java, and Perl APIs. It is used by many applications, including Python and Perl, so this should be installed on all systems.