DbMpoolFile::set_flags()

#include <db_cxx.h>

int
DbMpoolFile::set_flags(u_int32_t flags, bool onoff); 

Configure a file in the cache.

To set the flags for a particular database, call the DbMpoolFile::set_flags() method using the DbMpoolFile handle stored in the mpf field of the Db handle.

The DbMpoolFile::set_flags() 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

flags

The flags must be set to one of the following values:

  • DB_MPOOL_NOFILE

    If set, no backing temporary file will be opened for the specified in-memory database, even if it expands to fill the entire cache. Attempts to create new database pages after the cache has been filled will fail.

    The DB_MPOOL_NOFILE flag configures a file in the cache, not only operations performed using the specified DbMpoolFile handle.

    The DB_MPOOL_NOFILE flag may be used to configure Berkeley DB at any time during the life of the application.

  • DB_MPOOL_UNLINK

    If set, remove the file when the last reference to it is closed.

    The DB_MPOOL_ULINK flag configures a file in the cache, not only operations performed using the specified DbMpoolFile handle.

    The DB_MPOOL_ULINK flag may be used to configure Berkeley DB at any time during the life of the application.

onoff

If onoff is zero, the specified flags are cleared; otherwise they are set.

Class

DbEnv, DbMpoolFile

See Also

Memory Pools and Related Methods