Key-Value DB (an alternative to Berkeley DB?)

I'm looking for a hashmap on disk (Berkeley DB would fit exactly, but for the licensing problem). The requirements are:

FOSS w/a commercial-friendly license (can be used in commercial applications without a fee)
a C/C++ interface
Embeddable
decent speed? faster than SQLite would be ideal
cross-platform would also be nice

Any suggestions welcome. Thanks!

Solution

How about the *dbm libraries?

dbm ndbm gdbm sdbm tdbm and friends

Plenty to choose from.

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