DB_TXN->set_timeout
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#include <db.h>
u_int32_t
DB_TXN->set_timeout(DB_TXN *tid, db_timeout_t timeout, u_int32_t flags);
Description
The DB_TXN->set_timeout method sets timeout values for locks or
transactions for the specified transaction. The timeout value is
currently specified as an unsigned 32-bit number of microseconds,
limiting the maximum timeout to roughly 71 minutes.
The flags value must be set to one of the following values:
- DB_SET_LOCK_TIMEOUT
- Set the timeout value for locks in this transaction.
- DB_SET_TXN_TIMEOUT
- Set the timeout value for this transaction.
Timeouts are checked whenever a thread of control blocks on a lock or
when deadlock detection is performed. (In the case of
DB_SET_LOCK_TIMEOUT, the lock is one requested explicitly
through the Lock subsystem interfaces. In the case of
DB_SET_TXN_TIMEOUT, the lock is one requested on behalf of a
transaction. In either case, it may be a lock requested by the database
access methods underlying the application.) As timeouts are only
checked when the lock request first blocks or when deadlock detection
is performed, the accuracy of the timeout depends on how often deadlock
detection is performed.
Timeout values may be specified for the database environment as a whole.
See DB_ENV->set_timeout and for more information.
The DB_TXN->set_timeout method configures operations performed on the underlying
transaction, not only operations performed using the specified
DB_TXN handle.
The DB_TXN->set_timeout interface may be called at any time during the life of
the application.
The DB_TXN->set_timeout method returns a non-zero error value on failure and 0 on success.
Errors
The DB_TXN->set_timeout method may fail and return a non-zero error for the following conditions:
- EINVAL
- An invalid flag value or parameter was specified.
The DB_TXN->set_timeout method may fail and return a non-zero error for errors specified for other Berkeley DB and C library or system functions.
If a catastrophic error has occurred, the DB_TXN->set_timeout method may fail and
return DB_RUNRECOVERY,
in which case all subsequent Berkeley DB calls will fail in the same way.
Class
DB_ENV, DB_TXN
See Also
Transaction Subsystem and Related Methods
Copyright Sleepycat Software
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