DbEnv::lock_stat()

#include <db_cxx.h>

int
DbEnv::lock_stat(DB_LOCK_STAT **statp, u_int32_t flags); 

The DbEnv::lock_stat() method returns the locking subsystem statistics.

The DbEnv::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 DbEnv::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 DbEnv::lock_stat() method may not be called before the DbEnv::open() method is called.

The DbEnv::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 DbEnv::lock_stat() method may fail and throw a DbException exception, encapsulating one of the following non-zero errors, or return one of the following non-zero errors:

EINVAL

An invalid flag value or parameter was specified.

Class

DbEnv, DbLock

See Also

Locking Subsystem and Related Methods