Berkeley DB: txn_begin ee,hash,hashing,transaction,transactions,locking,logging,access method,access me thods,java,C,C++">

txn_begin

#include <db.h> int txn_begin(DB_TXNMGR *txnp, DB_TXN *parent, DB_TXN **tid); Description The txn_begin method creates a new transaction in the transaction manager, copying a pointer to a DB_TXN that uniquely identifies it into the memory referenced by tid. If the parent argument is non-NULL, the new transaction will be a nested transaction, with the transaction indicated by parent as its parent. Transactions may be nested to any level. Note: transactions may not span threads, i.e., each transaction must begin and end in the same thread, and each transaction may only be used by a single thread. Note: transactions may not span cursors, i.e., each transaction may only be used by a single cursor. The txn_begin function returns the value of errno on failure, and 0 on success. Errors If a fatal error occurs in Berkeley DB, the txn_begin function may fail and return DB_RUNRECOVERY, at which point all subsequent database calls will also return DB_RUNRECOVERY. The txn_begin function may fail and return errno for any of the errors specified for the following Berkeley DB and C library functions: abort(3), fcntl(3), fflush(3), fprintf(3), free(3), fsync(3), getpid(3), log_put, lseek(3), memset(3), mmap(3), munmap(3), shmat(3), shmdt(3), strerror(3), vfprintf(3), vsnprintf(3), and write(3). In addition, the txn_begin function may fail and return errno for the following conditions: ENOSPC The maximum number of concurrent transactions has been reached. See Also txn_abort, txn_begin, txn_checkpoint, txn_close, txn_commit, txn_id, txn_open, txn_prepare, txn_stat and txn_unlink.