int DbLockTab::id(u_int32_t *idp);
The DbLockTab::id method copies a locker ID, which is guaranteed to be unique in the specified lock table, into the memory location referenced by idp.
The Berkeley DB access methods generate a unique locker ID for each file that is opened with locking. During Berkeley DB access method operation, this locker ID will be used for all lock calls unless a transaction identifier was specified for the call, in which case the transaction ID specified is used as the locker ID.
The DbLockTab::id method either returns errno or throws an exception that encapsulates an errno on failure, and 0 on success.
The DbLockTab::id method may fail and throw an exception for any of the errors specified for the following Berkeley DB and C library functions: abort(3), fcntl(3), fprintf(3), and getpid(3).