Struct tracing::stdlib::os::fd::BorrowedFd

#[repr(transparent)]
pub struct BorrowedFd<'fd> {
    fd: i32,
    _phantom: PhantomData<&'fd OwnedFd>,
}

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.

Fields

fd: i32

_phantom: PhantomData<&'fd OwnedFd>

Implementations

impl BorrowedFd<'_>

pub const unsafe fn borrow_raw(fd: i32) -> BorrowedFd<'_>

Available on Unix only.

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, and it must not have the value -1.

impl BorrowedFd<'_>

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

Available on Unix only.

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

Trait Implementations

impl AsFd for BorrowedFd<'_>

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

Borrows the file descriptor.

impl AsRawFd for BorrowedFd<'_>

fn as_raw_fd(&self) -> i32

Extracts the raw file descriptor.

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

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

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for BorrowedFd<'_>

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

Formats the value using the given formatter.

impl IsTerminal for BorrowedFd<'_>

fn is_terminal(&self) -> bool

Returns true if the descriptor/handle refers to a terminal/tty.

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