#include <db.h> int db_env_set_func_pread(ssize_t (*func_pread)(int fd, void *buf, size_t nbytes, off_t offset));
Replace Berkeley DB calls to the IEEE/ANSI Std 1003.1 (POSIX) pread function with func_pread, which must conform to the standard interface specification.
The db_env_set_func_pread()
configures all operations performed
by a process and all of its threads of control, not operations
confined to a single database environment.
Although the db_env_set_func_pread()
may be called at any time
during the life of the application, it should normally be called
before making calls to the db_env_create or
db_create methods.
The db_env_set_func_pread()
function returns a non-zero error value on failure and 0 on success.