Struct lmdb_master_sys::MDB_val
source · #[repr(C)]pub struct MDB_val {
pub mv_size: usize,
pub mv_data: *mut c_void,
}
Expand description
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§
Auto Trait Implementations§
impl Freeze for MDB_val
impl RefUnwindSafe for MDB_val
impl !Send for MDB_val
impl !Sync for MDB_val
impl Unpin for MDB_val
impl UnwindSafe for MDB_val
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
🔬This is a nightly-only experimental API. (
clone_to_uninit
)