DBENV->set_errcall |
#include <db.h>void DBENV->set_errcall(DB_ENV *dbenv, void (*db_errcall_fcn)(const char *errpfx, char *msg));
The DBENV->set_errcall function is used to enhance the mechanism for reporting error messages to the application. In some cases, when an error occurs, Berkeley DB will call db_errcall_fcn with additional error information. The function must be declared with two arguments; the first will be the prefix string (as previously set by DB->set_errpfx or DBENV->set_errpfx), the second will be the error message string. It is up to the db_errcall_fcn function to display the error message in an appropriate manner.
Alternatively, you can use the DB->set_errfile or DBENV->set_errfile functions to display the additional information via a C library FILE *.
This error logging enhancement does not slow performance or significantly increase application size, and may be run during normal operation as well as during application debugging.
The DBENV->set_errcall interface may be used to configure Berkeley DB at any time during the life of the application.