impl<'fd> FdSet<'fd>

fn new() -> FdSet<'fd>

Create an empty FdSet

fn insert(&mut self, fd: BorrowedFd<'fd>)

Add a file descriptor to an FdSet

fn remove(&mut self, fd: BorrowedFd<'fd>)

Remove a file descriptor from an FdSet

fn contains(&self, fd: BorrowedFd<'fd>) -> bool

Test an FdSet for the presence of a certain file descriptor.

fn clear(&mut self)

Remove all file descriptors from this FdSet.

fn highest(&self) -> Option<BorrowedFd<'_>>

Finds the highest file descriptor in the set.

Returns None if the set is empty.

This can be used to calculate the nfds parameter of the select function.

Example

# use std::os::unix::io::{AsRawFd, BorrowedFd};
# use nix::sys::select::FdSet;
let fd_four = unsafe {BorrowedFd::borrow_raw(4)};
let fd_nine = unsafe {BorrowedFd::borrow_raw(9)};
let mut set = FdSet::new();
set.insert(fd_four);
set.insert(fd_nine);
assert_eq!(set.highest().map(|borrowed_fd|borrowed_fd.as_raw_fd()), Some(9));

fn fds(&self, highest: Option<RawFd>) -> Fds<'_, '_>

Returns an iterator over the file descriptors in the set.

For performance, it takes an optional higher bound: the iterator will not return any elements of the set greater than the given file descriptor.

Examples

# use nix::sys::select::FdSet;
# use std::os::unix::io::{AsRawFd, BorrowedFd, RawFd};
let mut set = FdSet::new();
let fd_four = unsafe {BorrowedFd::borrow_raw(4)};
let fd_nine = unsafe {BorrowedFd::borrow_raw(9)};
set.insert(fd_four);
set.insert(fd_nine);
let fds: Vec<RawFd> = set.fds(None).map(|borrowed_fd|borrowed_fd.as_raw_fd()).collect();
assert_eq!(fds, vec![4, 9]);