Struct std::process::ChildStdout

[+] Show declaration

pub struct ChildStdout { /* fields omitted */ }

[−] Expand description

A handle to a child process's standard output (stdout).

This struct is used in the stdout field on Child.

When an instance of ChildStdout is dropped, the ChildStdout's underlying file handle will be closed.

Trait Implementations

impl Read for ChildStdout[+]

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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>[−]

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

unsafe fn initializer(&self) -> Initializer[−]

🔬 This is a nightly-only experimental API. (read_initializer #42788)

Determines if this Reader can work with buffers of uninitialized memory.

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

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

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

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

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

Read the exact number of bytes required to fill buf.

Important traits for &'_ mut F

impl<'_, F> Future for &'_ mut F where
    F: Unpin + Future + ?Sized,  type Output = <F as Future>::Output;impl<'_, I> Iterator for &'_ mut I where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;impl<'_, R: Read + ?Sized> Read for &'_ mut Rimpl<'_, W: Write + ?Sized> Write for &'_ mut W

fn by_ref(&mut self) -> &mut Self where
    Self: Sized, [−]

Creates a "by reference" adaptor for this instance of Read.

Important traits for Bytes<R>

impl<R: Read> Iterator for Bytes<R> type Item = Result<u8>;

fn bytes(self) -> Bytes<Self> where
    Self: Sized, [−]

Transforms this Read instance to an [Iterator] over its bytes.

Important traits for Chain<T, U>

impl<T: Read, U: Read> Read for Chain<T, U>

fn chain<R: Read>(self, next: R) -> Chain<Self, R> where
    Self: Sized, [−]

Creates an adaptor which will chain this stream with another.

Important traits for Take<T>

impl<T: Read> Read for Take<T>

fn take(self, limit: u64) -> Take<Self> where
    Self: Sized, [−]

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

impl AsRawFd for ChildStdout[+]

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fn as_raw_fd(&self) -> RawFd[−]

This is supported on Unix only.

Extracts the raw file descriptor.

impl IntoRawFd for ChildStdout[+]

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fn into_raw_fd(self) -> RawFd[−]

This is supported on Unix only.

Consumes this object, returning the raw underlying file descriptor.

impl AsRawHandle for ChildStdout[+]

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fn as_raw_handle(&self) -> RawHandle[−]

This is supported on Windows only.

Extracts the raw handle, without taking any ownership.

impl IntoRawHandle for ChildStdout[+]

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fn into_raw_handle(self) -> RawHandle[−]

This is supported on Windows only.

Consumes this object, returning the raw underlying handle.

impl Debug for ChildStdout[+]

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fn fmt(&self, f: &mut Formatter) -> Result[−]

Formats the value using the given formatter.

impl From<ChildStdout> for Stdio[+]

fn from(child: ChildStdout) -> Stdio[−]

Converts a ChildStdout into a Stdio

Examples

ChildStdout will be converted to Stdio using Stdio::from under the hood.

use std::process::{Command, Stdio};

let hello = Command::new("echo")
    .arg("Hello, world!")
    .stdout(Stdio::piped())
    .spawn()
    .expect("failed echo command");

let reverse = Command::new("rev")
    .stdin(hello.stdout.unwrap())  // Converted into a Stdio here
    .output()
    .expect("failed reverse command");

assert_eq!(reverse.stdout, b"!dlrow ,olleH\n");