open-database returns nil when type is berkeley-db.
However, three files are left open in the process of returning nil.
(open-database vm-folders-summary-database 'berkeley-db 'hash "rw+")
nil
(open-database vm-folders-summary-database nil 'hash "rw+")
#<database "/home/jeff/mail/.vm.folders.db" (dbm/nil/readwrite) 0xd245>
This is part of the configuration output of building 21.4.6
-jeff
checking for ndbm.h... yes
checking for dbm_open in -lgdbm... yes
checking for Berkeley db.h... db.h
checking for Berkeley DB version... 3
checking for db_create... no
checking for db_create in -ldb... yes
Databases:
Compiling in support for Berkeley database.
Compiling in support for GNU DBM.
Compiling in support for LDAP.