Enum OpenFile 

pub enum OpenFile {
    Stdin(Stdin),
    Stdout(Stdout),
    Stderr(Stderr),
    File(Arc<File>),
    PipeReader(Arc<PipeReader>),
    PipeWriter(Arc<PipeWriter>),
    Stream(Box<dyn Stream>),
}

Represents a file open in a shell context.

File- and pipe-backed variants hold their handle behind an Arc, so cloning an OpenFile shares the underlying descriptor by reference count. The shell opens a fresh context for each subshell, command substitution, background job, and function call and runs them as in-process tasks against one process-wide descriptor table (rather than via fork(2) like a traditional shell); sharing the descriptor keeps deeply nested or highly concurrent execution from exhausting that table. A descriptor is duplicated for real only when an independently owned copy is needed to hand to an external child process — see OpenFile::try_clone_to_owned and the Stdio conversion below.

Variants

Stdin(Stdin)

The original standard input this process was started with.

Stdout(Stdout)

The original standard output this process was started with.

Stderr(Stderr)

The original standard error this process was started with.

File(Arc<File>)

A file open for reading or writing.

PipeReader(Arc<PipeReader>)

A read end of a pipe.

PipeWriter(Arc<PipeWriter>)

A write end of a pipe.

Stream(Box<dyn Stream>)

A custom stream.

Implementations

impl OpenFile

pub fn try_borrow_as_fd(&self) -> Result<BorrowedFd<'_>, Error>

Available on Unix only.

Borrows the open file as a BorrowedFd.

Errors

Returns an error if the operation is not supported for the underlying file type.

pub fn is_terminal(&self) -> bool

Checks if the open file is associated with a terminal.

Trait Implementations

impl Clone for OpenFile

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'de> Deserialize<'de> for OpenFile

Available on crate feature serde only.

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for OpenFile

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

Formats the value using the given formatter.

impl From<File> for OpenFile

fn from(file: File) -> Self

Converts to this type from the input type.

impl From<PipeReader> for OpenFile

fn from(reader: PipeReader) -> Self

Converts to this type from the input type.

impl From<PipeWriter> for OpenFile

fn from(writer: PipeWriter) -> Self

Converts to this type from the input type.

impl From<Stderr> for OpenFile

fn from(stderr: Stderr) -> Self

Creates an OpenFile from standard error.

impl From<Stdin> for OpenFile

fn from(stdin: Stdin) -> Self

Creates an OpenFile from standard input.

impl From<Stdout> for OpenFile

fn from(stdout: Stdout) -> Self

Creates an OpenFile from standard output.

impl Read for OpenFile

fn read(&mut self, buf: &mut [u8]) -> Result<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

fn is_read_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Reader has an efficient read_vectored implementation.

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Reads all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Reads all bytes until EOF in this source, appending them to buf.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Reads the exact number of bytes required to fill buf.

fn read_buf(&mut self, buf: BorrowedCursor<'_, u8>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Pull some bytes from this source into the specified buffer.

fn read_buf_exact( &mut self, cursor: BorrowedCursor<'_, u8>, ) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Reads the exact number of bytes required to fill cursor.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Read.

fn bytes(self) -> Bytes<Self>

where Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

fn chain<R>(self, next: R) -> Chain<Self, R>

where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another.

fn take(self, limit: u64) -> Take<Self>

where Self: Sized,

Creates an adapter which will read at most limit bytes from it.

fn read_array<const N: usize>(&mut self) -> Result<[u8; N], Error>

where Self: Sized,

🔬This is a nightly-only experimental API. (read_array)

Read and return a fixed array of bytes from this source.

fn read_le<T>(&mut self) -> Result<T, Error>

where T: FromEndianBytes, Self: Sized,

🔬This is a nightly-only experimental API. (read_le)

Read and return a type (e.g. an integer) in little-endian order.

fn read_be<T>(&mut self) -> Result<T, Error>

where T: FromEndianBytes, Self: Sized,

🔬This is a nightly-only experimental API. (read_le)

Read and return a type (e.g. an integer) in big-endian order.

impl Serialize for OpenFile

Available on crate feature serde only.

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl TryFrom<OpenFile> for Stdio

type Error = Error

The type returned in the event of a conversion error.

fn try_from(open_file: OpenFile) -> Result<Self, Self::Error>

Performs the conversion.

impl Write for OpenFile

fn write(&mut self, buf: &[u8]) -> Result<usize>

Writes a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flushes this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

fn is_write_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Writer has an efficient write_vectored implementation.

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

🔬This is a nightly-only experimental API. (write_all_vectored)

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, args: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Write.