Struct Unbuffered 

pub struct Unbuffered;

A file opened with no intermediate buffering: its transfers reach the device, so it can claim WarrantyClass::SharedDevice, and need the device’s sector alignment. Per-write write-through is honoured only on such a file, which the kernel refuses on a cached one (error 509, measured 2026-10-07 and kept as a test), so it offers that capability.

Implementations

impl Unbuffered

pub const DEFAULT_SECTOR_SIZE: u32 = 4096

The sector size an unbuffered file is given until OpenedFile::with_sector_size says otherwise: the largest in general use, which every smaller one divides, so no device refuses it. A caller whose device allows less can say so and be offered less alignment to meet.

Trait Implementations

impl Buffering for Unbuffered

const FLAGS: u32 = FILE_FLAG_NO_BUFFERING

The CreateFileW flags this mode opens with.

const WARRANTY: WarrantyClass = WarrantyClass::SharedDevice

The warranty class a file in this mode can claim.

const CAPABILITIES: Capabilities

What a file in this mode offers beyond the contract’s obligations.

const LOCAL_DEVICE_ONLY: bool = true

Whether the claim in WARRANTY holds only on a device of this machine, so that a file on a remote one is refused rather than given a class it cannot keep.

fn geometry() -> Geometry

The alignment a file in this mode starts with.

fn sector_geometry(sector_size: u32) -> Result<Geometry, GeometryError>

The alignment a raw volume or disk in this mode needs, addressed in sectors of sector_size bytes. Its transfers are whole sectors in either mode, so offsets and lengths are aligned to one; its buffers only when it is unbuffered, as the cache is what lets a cached transfer start anywhere.

impl Clone for Unbuffered

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Unbuffered

impl Debug for Unbuffered

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

Formats the value using the given formatter.