DB_ENV->lock_stat()

#include <db.h>

int
DB_ENV->lock_stat(DB_ENV *env, DB_LOCK_STAT **statp, u_int32_t flags);  

The DB_ENV->lock_stat() method returns the locking subsystem statistics.

The DB_ENV->lock_stat() method creates a statistical structure of type DB_LOCK_STAT and copies a pointer to it into a user-specified memory location.

Statistical structures are stored in allocated memory. If application-specific allocation routines have been declared (see DB_ENV->set_alloc() for more information), they are used to allocate the memory; otherwise, the standard C library malloc(3) is used. The caller is responsible for deallocating the memory. To deallocate the memory, free the memory reference; references inside the returned memory need not be individually freed.

The following DB_LOCK_STAT fields will be filled in:

The DB_ENV->lock_stat() method may not be called before the DB_ENV->open() method is called.

The DB_ENV->lock_stat() method returns a non-zero error value on failure and 0 on success.

Parameters

statp

The statp parameter references memory into which a pointer to the allocated statistics structure is copied.

flags

The flags parameter must be set to 0 or the following value:

  • DB_STAT_CLEAR

    Reset statistics after returning their values.

Errors

The DB_ENV->lock_stat() method may fail and return one of the following non-zero errors:

EINVAL

An invalid flag value or parameter was specified.

Class

DB_ENV, DB_LOCK

See Also

Locking Subsystem and Related Methods