db_env_set_func_open |
#include <db.h>int db_env_set_func_open(int (*func_open)(const char *path, int flags, int mode));
Replace Berkeley DB calls to the IEEE/ANSI Std 1003.1 (POSIX) open function with func_open, which must conform to the standard interface.
The db_env_set_func_open interface affects the entire application, not a single database or database environment.
While the db_env_set_func_open interface may be used to configure Berkeley DB at any time during the life of the application, it should normally be called before making any calls to the db_env_create or db_create functions.
The db_env_set_func_open function returns a non-zero error value on failure and 0 on success.