#include <db.h>

int
DB_ENV->cdsgroup_begin(DB_ENV *dbenv, DB_TXN **tid);  

The DB_ENV->cdsgroup_begin() method allocates a locker ID in an environment configured for Berkeley DB Concurrent Data Store applications. It copies a pointer to a DB_TXN that uniquely identifies the locker ID into the memory to which tid refers. Calling the DB_TXN->commit() method will discard the allocated locker ID.

See Berkeley DB Concurrent Data Store applications for more information about when this is required.

This method may not be called on a sliced database.

The DB_ENV->cdsgroup_begin() method may be called at any time during the life of the application.

The DB_ENV->cdsgroup_begin() method returns a non-zero error value on failure and 0 on success.