Special compile-time flags are required when compiling threaded applications on FreeBSD. If you are compiling a threaded application, you must compile with the _THREAD_SAFE and -pthread flags:

cc -D_THREAD_SAFE -pthread ...

The Berkeley DB library will automatically build with the correct options.

Some FreeBSD releases are known to return ENOLCK from fsync and close calls on NFS-mounted filesystems, even though the call has succeeded. The Berkeley DB code should be modified to ignore ENOLCK errors, or no Berkeley DB files should be placed on NFS-mounted filesystems on these systems.