Struct File

pub struct File { /* private fields */ }

A reference to an open file on a filesystem.

This corresponds to async_std::fs::File.

This File has no open or create methods. To open or create a file, first obtain a Dir containing the path, and then call Dir::open or Dir::create.

Implementations

impl File

pub fn from_std(std: File) -> Self

Constructs a new instance of Self from the given async_std::fs::File.

This grants access the resources the async_std::fs::File instance already has access to.

pub fn into_std(self) -> File

Consumes self and returns an async_std::fs::File.

pub async fn sync_all(&self) -> Result<()>

Attempts to sync all OS-internal metadata to disk.

This corresponds to async_std::fs::File::sync_all.

pub async fn sync_data(&self) -> Result<()>

This function is similar to sync_all, except that it may not synchronize file metadata to a filesystem.

This corresponds to async_std::fs::File::sync_data.

pub async fn set_len(&self, size: u64) -> Result<()>

Truncates or extends the underlying file, updating the size of this file to become size.

This corresponds to async_std::fs::File::set_len.

pub async fn metadata(&self) -> Result<Metadata>

Queries metadata about the underlying file.

This corresponds to async_std::fs::File::metadata.

pub async fn set_permissions(&self, perm: Permissions) -> Result<()>

Changes the permissions on the underlying file.

This corresponds to async_std::fs::File::set_permissions.

pub async fn open_ambient<P: AsRef<Path>>( path: P, ambient_authority: AmbientAuthority, ) -> Result<Self>

Constructs a new instance of Self in read-only mode by opening the given path as a file using the host process’ ambient authority.

Ambient Authority

This function is not sandboxed and may access any path that the host process has access to.

pub async fn create_ambient<P: AsRef<Path>>( path: P, ambient_authority: AmbientAuthority, ) -> Result<Self>

Constructs a new instance of Self in write-only mode by opening, creating or truncating, the given path as a file using the host process’ ambient authority.

Ambient Authority

This function is not sandboxed and may access any path that the host process has access to.

pub async fn open_ambient_with<P: AsRef<Path>>( path: P, options: &OpenOptions, ambient_authority: AmbientAuthority, ) -> Result<Self>

Constructs a new instance of Self with the options specified by options by opening the given path as a file using the host process’ ambient authority.

Ambient Authority

This function is not sandboxed and may access any path that the host process has access to.

pub fn options() -> OpenOptions

Returns a new OpenOptions object.

This corresponds to [async_std::fs::File::options].

Trait Implementations

impl AsFd for File

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

Borrows the file descriptor.

impl AsRawFd for File

fn as_raw_fd(&self) -> RawFd

Extracts the raw file descriptor.

impl Clone for File

fn clone(&self) -> File

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for File

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

Formats the value using the given formatter.

impl From<File> for OwnedFd

fn from(file: File) -> OwnedFd

Converts to this type from the input type.

impl From<OwnedFd> for File

fn from(fd: OwnedFd) -> Self

Converts to this type from the input type.

impl FromRawFd for File

unsafe fn from_raw_fd(fd: RawFd) -> Self

Constructs a new instance of Self from the given raw file descriptor.

impl IntoRawFd for File

fn into_raw_fd(self) -> RawFd

Consumes this object, returning the raw underlying file descriptor.

impl AsyncRead for &File

fn poll_read( self: Pin<&mut Self>, cx: &mut Context<'_>, buf: &mut [u8], ) -> Poll<Result<usize>>

Attempt to read from the AsyncRead into buf.

fn poll_read_vectored( self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &mut [IoSliceMut<'_>], ) -> Poll<Result<usize>>

Attempt to read from the AsyncRead into bufs using vectored IO operations.

impl AsyncRead for File

fn poll_read( self: Pin<&mut Self>, cx: &mut Context<'_>, buf: &mut [u8], ) -> Poll<Result<usize>>

Attempt to read from the AsyncRead into buf.

fn poll_read_vectored( self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &mut [IoSliceMut<'_>], ) -> Poll<Result<usize>>

Attempt to read from the AsyncRead into bufs using vectored IO operations.

impl AsyncSeek for &File

fn poll_seek( self: Pin<&mut Self>, cx: &mut Context<'_>, pos: SeekFrom, ) -> Poll<Result<u64>>

Attempt to seek to an offset, in bytes, in a stream.

impl AsyncSeek for File

fn poll_seek( self: Pin<&mut Self>, cx: &mut Context<'_>, pos: SeekFrom, ) -> Poll<Result<u64>>

Attempt to seek to an offset, in bytes, in a stream.

impl AsyncWrite for &File

fn poll_write( self: Pin<&mut Self>, cx: &mut Context<'_>, buf: &[u8], ) -> Poll<Result<usize>>

Attempt to write bytes from buf into the object.

fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>>

Attempt to flush the object, ensuring that any buffered data reach their destination.

fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>>

Attempt to close the object.

fn poll_write_vectored( self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>], ) -> Poll<Result<usize>>

Attempt to write bytes from bufs into the object using vectored IO operations.

impl AsyncWrite for File

fn poll_write( self: Pin<&mut Self>, cx: &mut Context<'_>, buf: &[u8], ) -> Poll<Result<usize>>

Attempt to write bytes from buf into the object.

fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>>

Attempt to flush the object, ensuring that any buffered data reach their destination.

fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>>

Attempt to close the object.

fn poll_write_vectored( self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>], ) -> Poll<Result<usize>>

Attempt to write bytes from bufs into the object using vectored IO operations.

impl FilelikeViewType for File