#include <db.h>

DB_ENV->set_feedback(DB_ENV *dbenv,
    void (*db_feedback_fcn)(DB_ENV *dbenv, int opcode, int percent));  

Some operations performed by the Berkeley DB library can take non-trivial amounts of time. The DB_ENV->set_feedback() method can be used by applications to monitor progress within these operations. When an operation is likely to take a long time, Berkeley DB will call the specified callback function with progress information.


Berkeley DB is not re-entrant. Callback functions should not attempt to make library calls (for example, to release locks or close open handles). Re-entering Berkeley DB is not guaranteed to work correctly, and the results are undefined.

It is up to the callback function to display this information in an appropriate manner.

The DB_ENV->set_feedback() method configures operations performed using the specified DB_ENV handle.

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

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



The db_feedback_fcn parameter is the application-specified feedback function called to report Berkeley DB operation progress. The callback function must take three parameters:

  • dbenv

    The dbenv parameter is a reference to the enclosing database environment.

  • opcode

    The opcode parameter is an operation code. The opcode parameter may take on any of the following values:


      The environment is being recovered.

  • percent

    The percent parameter is the percent of the operation that has been completed, specified as an integer value between 0 and 100.



See Also

Database Environments and Related Methods