Library Version 18.1.40

DbEnv::log_get_config()
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DbEnv::log_get_config() 

#include <db_cxx.h>

int
DbEnv::log_get_config(u_int32_t which, int *onoffp)

The DbEnv::log_get_config() method returns whether the specified which parameter is currently set or not. You can manage this value using the DbEnv::log_set_config() method.

The DbEnv::log_get_config() method may be called at any time during the life of the application.

The DbEnv::log_get_config() method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success.

Parameters

which

The which parameter is the message value for which configuration is being checked. Must be set to one of the following values:

  • DB_LOG_EXT_FILE

    Enables full logging of external file data.

  • DB_LOG_DIRECT

    System buffering is turned off for Berkeley DB log files to avoid double caching.

  • DB_LOG_DSYNC

    Berkeley DB is configured to flush log writes to the backing disk before returning from the write system call, rather than flushing log writes explicitly in a separate system call, as necessary.

  • DB_LOG_AUTO_REMOVE

    Berkeley DB automatically removes log files that are no longer needed.

  • DB_LOG_IN_MEMORY

    Transaction logs are maintained in memory rather than on disk. This means that transactions exhibit the ACI (atomicity, consistency, and isolation) properties, but not D (durability).

  • DB_LOG_NOSYNC

    The transaction log is not flushed from from the operating system cache to stable storage when the logging system switches log files or a durable transaction commits. This means that transactions exhibit the ACI (atomicity, consistency, and isolation) properties, but only partially support D (durability); that is, database integrity will be maintained if the application fails and the environment is recovered, but not if the system fails. All database files must be verified and/or restored from a replication group master or archival backup after system failure.

  • DB_LOG_ZERO

    All pages of a log file are zeroed when that log file is created.

onoffp

The onoffp parameter references memory into which the configuration of the specified which parameter is copied.

If the returned onoff value is zero, the parameter is off; otherwise, on.

Class

DbEnv

See Also

Logging Subsystem and Related Methods, DbEnv::log_set_config()

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