Does Tokyo Cabinet support in-memory B+ trees? If so, how do I use them? Because in some web articles (for example here and here), such usage is reported but I can't find any document describing how to do it. Thanks.
The documentation describes tcadbopen(TCADB *adb, const char *name) as follows:
`name' specifies the name of the database. If it is "*", the database will be an on-memory hash database. If it is "+", the database will be an on-memory tree database.
So, the name "+" does what you want.