Struct io_lifetimes::OptionFileHandle

#[repr(transparent)]
pub struct OptionFileHandle { /* fields omitted */ }

Similar to Option<OwnedHandle>, but intended for use in FFI interfaces where [INVALID_HANDLE_VALUE] is used as the sentry value, and null values are not used at all, such as in the return value of CreateFileW.

If this holds an owned handle, it closes the handle on drop.

This uses repr(transparent) and has the representation of a host handle, so it can be used in FFI in places where a non-null handle is passed as a consumed argument or returned as an owned value, or it is [INVALID_HANDLE_VALUE] indicating an error or an otherwise absent value.

Implementations

impl OptionFileHandle

pub const fn none() -> Self

Return an empty OptionFileHandle with no resource.

Trait Implementations

impl Debug for OptionFileHandle

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

Formats the value using the given formatter.

impl Drop for OptionFileHandle

fn drop(&mut self)

Executes the destructor for this type.

impl From<OwnedHandle> for OptionFileHandle

fn from(owned: OwnedHandle) -> Self

Performs the conversion.

impl FromHandle for OptionFileHandle

fn from_handle(owned: OwnedHandle) -> Self

Constructs a new instance of Self from the given handle.

fn from_into_handle<Owned: IntoHandle>(into_owned: Owned) -> Self where
    Self: Sized, 

Constructs a new instance of Self from the given handle converted from into_owned.

impl FromRawHandle for OptionFileHandle

unsafe fn from_raw_handle(raw: RawHandle) -> Self

Constructs a new instance of Self from the given raw handle.

Safety

The resource pointed to by raw must be either open and otherwise unowned, or equal to [INVALID_FILE_HANDLE]. Note that not all Windows APIs use [INVALID_HANDLE_VALUE] for errors; see here for the full story.

impl TryFrom<OptionFileHandle> for OwnedHandle

type Error = ()

The type returned in the event of a conversion error.

fn try_from(option: OptionFileHandle) -> Result<Self, ()>

Performs the conversion.

impl Send for OptionFileHandle

impl Sync for OptionFileHandle