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BorrowedFd

Struct BorrowedFd 

1.66.0 · Source
#[repr(transparent)]
pub struct BorrowedFd<'fd> { fd: NotAllOnes<RawFd>, _phantom: PhantomData<&'fd OwnedFd>, }
Available on Hermit or Motor OS or Trusty or Unix or WASI only.
Expand description

A borrowed file descriptor.

This has a lifetime parameter to tie it to the lifetime of something that owns the file descriptor. For the duration of that lifetime, it is guaranteed that nobody will close the file descriptor.

This uses repr(transparent) and has the representation of a host file descriptor, so it can be used in FFI in places where a file descriptor is passed as an argument, it is not captured or consumed, and it never has the value -1.

This type does not have a ToOwned implementation. Calling .to_owned() on a variable of this type will call it on &BorrowedFd and use Clone::clone() like ToOwned does for all types implementing Clone. The result will be descriptor borrowed under the same lifetime.

To obtain an OwnedFd, you can use BorrowedFd::try_clone_to_owned instead, but this is not supported on all platforms.

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§fd: NotAllOnes<RawFd>§_phantom: PhantomData<&'fd OwnedFd>

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impl BorrowedFd<'_>

1.63.0 (const: 1.63.0) · Source

pub const unsafe fn borrow_raw(fd: RawFd) -> Self

Returns a BorrowedFd holding the given raw file descriptor.

§Safety

The resource pointed to by fd must remain open for the duration of the returned BorrowedFd.

§Panics

Panics if the raw file descriptor has the value -1.

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impl BorrowedFd<'_>

1.63.0 · Source

pub fn try_clone_to_owned(&self) -> Result<OwnedFd>

Available on neither Hermit, nor Motor OS, nor Trusty, nor WebAssembly and non-Emscripten.

Creates a new OwnedFd instance that shares the same underlying file description as the existing BorrowedFd instance.

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1.63.0 · Source§

impl AsFd for BorrowedFd<'_>

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fn as_fd(&self) -> BorrowedFd<'_>

Borrows the file descriptor. Read more
1.63.0 · Source§

impl AsRawFd for BorrowedFd<'_>

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fn as_raw_fd(&self) -> RawFd

Extracts the raw file descriptor. Read more
1.63.0 · Source§

impl<'fd> Clone for BorrowedFd<'fd>

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fn clone(&self) -> BorrowedFd<'fd>

Returns a duplicate of the value. Read more
1.0.0 (const: unstable) · Source§

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

Performs copy-assignment from source. Read more
1.63.0 · Source§

impl<'fd> Copy for BorrowedFd<'fd>

1.63.0 · Source§

impl Debug for BorrowedFd<'_>

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

Formats the value using the given formatter. Read more
1.70.0 · Source§

impl IsTerminal for BorrowedFd<'_>

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fn is_terminal(&self) -> bool

Returns true if the descriptor/handle refers to a terminal/tty. Read more
1.63.0 · Source§

impl<'fd> TrivialClone for BorrowedFd<'fd>

Auto Trait Implementations§

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impl<'fd> Freeze for BorrowedFd<'fd>

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impl<'fd> RefUnwindSafe for BorrowedFd<'fd>

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impl<'fd> Send for BorrowedFd<'fd>

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impl<'fd> Sync for BorrowedFd<'fd>

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impl<'fd> Unpin for BorrowedFd<'fd>

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impl<'fd> UnsafeUnpin for BorrowedFd<'fd>

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impl<'fd> UnwindSafe for BorrowedFd<'fd>

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> CloneToUninit for T
where T: Clone,

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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit #126799)
Performs copy-assignment from self to dest. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> Printable for T
where T: Copy + Debug,

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impl<T> SizeHint for T
where T: ?Sized,

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default fn lower_bound(&self) -> usize

🔬This is a nightly-only experimental API. (core_io_internals)
Returns a lower bound on the number of elements this container-like item contains. For example, an array [u8; 12] could return any value between 0 and 12 inclusively as a correct implementation. Read more
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default fn upper_bound(&self) -> Option<usize>

🔬This is a nightly-only experimental API. (core_io_internals)
Returns an upper bound on the number of elements this container-like item contains if it can be determined, otherwise None. Read more
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final fn size_hint(&self) -> (usize, Option<usize>)

🔬This is a nightly-only experimental API. (core_io_internals)
Returns an estimate for the number of elements this container like type contains. Read more
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impl<T> SizedTypeProperties for T

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#[doc(hidden)]
const SIZE: usize = _

🔬This is a nightly-only experimental API. (sized_type_properties)
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#[doc(hidden)]
const ALIGN: usize = _

🔬This is a nightly-only experimental API. (sized_type_properties)
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#[doc(hidden)]
const ALIGNMENT: Alignment = _

🔬This is a nightly-only experimental API. (ptr_alignment_type #102070)
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#[doc(hidden)]
const IS_ZST: bool = _

🔬This is a nightly-only experimental API. (sized_type_properties)
true if this type requires no storage. false if its size is greater than zero. Read more
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#[doc(hidden)]
const LAYOUT: Layout = _

🔬This is a nightly-only experimental API. (sized_type_properties)
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#[doc(hidden)]
const MAX_SLICE_LEN: usize = _

🔬This is a nightly-only experimental API. (sized_type_properties)
The largest safe length for a [Self]. Read more
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impl<T> ToOwned for T
where T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.