Why would Berkeley DB operations return errors like EINVAL when it appears that Im using the API correctly?
The application is failing to zero out DBT objects before calling Berkeley DB. Before using a DBT, you must initialize all its elements to 0 and then set the ones you are using explicitly. Another reason for this symptom is the application may be using Berkeley DB handles in a free-threaded manner, without specifying the DB_THREAD flag to the DB->open or DB_ENV->open methods. Any time you are sharing a handle across multiple threads, you must specify DB_THREAD when you open that handle. Another reason for this symptom is the application is concurrently accessing the database, but not acquiring locks. The Berkeley DB Data Store product does no locking at all; the application must do its own serialization of access to the database to avoid corruption. The Berkeley DB Concurrent Data Store and Berkeley DB Transactional Data Store products do lock the database, but still require that locking be configured.
This generally happens when using uninitialized memory. It is the responsiblity of the application to zero out the DBT objects before invoking the Berkeley DB API. Before using a DBT, you must initialize all its elements to 0 and then set the ones you are using explicitly. Another common explanation of this symptom is the application may be using Berkeley DB handles in a free-threaded manner, without specifying the DB_THREAD flag to the DB->open or DB_ENV->open methods. Any time you are sharing a handle across multiple threads, you must specify DB_THREAD when you open that handle. Another reason for this symptom is the application is concurrently accessing the database, but not acquiring locks. The Berkeley DB Data Store product does no locking at all; the application must do its own serialization of access to the database to avoid corruption. The Berkeley DB Concurrent Data Store and Berkeley DB Transactional Data Store products do lock the database, but still require that locking be
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