Struct FileDescriptorReservation

pub struct FileDescriptorReservation { /* private fields */ }

A file descriptor reservation.

This allows the creation of a file descriptor in two steps: first, we reserve a slot for it, then we commit or drop the reservation. The first step may fail (e.g., the current process ran out of available slots), but commit and drop never fail (and are mutually exclusive).

Dropping the reservation happens in the destructor of this type.

Invariants

The fd stored in this struct must correspond to a reserved file descriptor of the current task.

Implementations

impl FileDescriptorReservation

pub fn get_unused_fd_flags(flags: u32) -> Result<Self>

Creates a new file descriptor reservation.

pub fn reserved_fd(&self) -> u32

Returns the file descriptor number that was reserved.

pub fn fd_install(self, file: ARef<File>)

Commits the reservation.

The previously reserved file descriptor is bound to file. This method consumes the FileDescriptorReservation, so it will not be usable after this call.

Trait Implementations

impl Drop for FileDescriptorReservation

fn drop(&mut self)

Executes the destructor for this type.