Struct MDB_val

#[repr(C)]
pub struct MDB_val {
    pub mv_size: usize,
    pub mv_data: *mut c_void,
}

Generic structure used for passing keys and data in and out of the database.

Values returned from the database are valid only until a subsequent update operation, or the end of the transaction. Do not modify or free them, they commonly point into the database itself.

Key sizes must be between 1 and #mdb_env_get_maxkeysize() inclusive. The same applies to data sizes in databases with the #MDB_DUPSORT flag. Other data items can in theory be from 0 to 0xffffffff bytes long.

Fields

mv_size: usize

< size of the data item

mv_data: *mut c_void

< address of the data item

Trait Implementations

impl Clone for MDB_val

fn clone(&self) -> MDB_val

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MDB_val

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Copy for MDB_val

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 16 bytes