Struct PollFd

pub struct PollFd<'fd> { /* private fields */ }

Available on crate feature poll only.

This is a wrapper around libc::pollfd.

It’s meant to be used as an argument to the poll and ppoll functions to specify the events of interest for a specific file descriptor.

After a call to poll or ppoll, the events that occurred can be retrieved by calling revents() on the PollFd object from the array passed to poll.

Implementations

impl<'fd> PollFd<'fd>

pub fn new(fd: BorrowedFd<'fd>, events: PollFlags) -> PollFd<'fd>

Creates a new PollFd specifying the events of interest for a given file descriptor.

Examples

let (r, w) = pipe().unwrap();
let pfd = PollFd::new(r.as_fd(), PollFlags::POLLIN);

These are placed in an array and passed to poll or ppoll.

pub fn revents(&self) -> Option<PollFlags>

Returns the events that occurred in the last call to poll or ppoll. Will only return None if the kernel provides status flags that Nix does not know about.

pub fn any(&self) -> Option<bool>

Returns if any of the events of interest occured in the last call to poll or ppoll. Will only return None if the kernel provides status flags that Nix does not know about.

Equivalent to x.revents()? != PollFlags::empty().

This is marginally more efficient than PollFd::all.

pub fn all(&self) -> Option<bool>

Returns if all the events of interest occured in the last call to poll or ppoll. Will only return None if the kernel provides status flags that Nix does not know about.

Equivalent to x.revents()? & x.events() == x.events().

This is marginally less efficient than PollFd::any.

pub fn events(&self) -> PollFlags

The events of interest for this PollFd.

pub fn set_events(&mut self, events: PollFlags)

Modify the events of interest for this PollFd.

Trait Implementations

impl AsFd for PollFd<'_>

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

Borrows the file descriptor.

impl<'fd> Clone for PollFd<'fd>

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

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'fd> Debug for PollFd<'fd>

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

Formats the value using the given formatter.

impl<'fd> Hash for PollFd<'fd>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<'fd> PartialEq for PollFd<'fd>

fn eq(&self, other: &PollFd<'fd>) -> bool

Tests for self and other values to be equal, and is used by ==.

const fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'fd> Eq for PollFd<'fd>

impl<'fd> StructuralPartialEq for PollFd<'fd>