Struct std::process::ChildStderr

pub struct ChildStderr { /* private fields */ }

A handle to a child process’s stderr.

This struct is used in the stderr field on Child.

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

Trait Implementations

impl AsFd for ChildStderr

This is supported on Unix only.

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

🔬 This is a nightly-only experimental API. (io_safety #87074)

Borrows the file descriptor.

impl AsHandle for ChildStderr

This is supported on Windows only.

fn as_handle(&self) -> BorrowedHandle<'_>

🔬 This is a nightly-only experimental API. (io_safety #87074)

Borrows the handle.

impl AsRawFd for ChildStderr

This is supported on Unix only.

fn as_raw_fd(&self) -> RawFd

Extracts the raw file descriptor.

impl AsRawHandle for ChildStderr

This is supported on Windows only.

fn as_raw_handle(&self) -> RawHandle

Extracts the raw handle, without taking any ownership.

impl Debug for ChildStderr

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

Formats the value using the given formatter.

impl From<ChildStderr> for OwnedFd

This is supported on Unix only.

fn from(child_stderr: ChildStderr) -> OwnedFd

Performs the conversion.

impl From<ChildStderr> for OwnedHandle

This is supported on Windows only.

fn from(child_stderr: ChildStderr) -> OwnedHandle

Performs the conversion.

impl From<ChildStderr> for Stdio

fn from(child: ChildStderr) -> Stdio

Converts a ChildStderr into a Stdio

Examples

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

let reverse = Command::new("rev")
    .arg("non_existing_file.txt")
    .stderr(Stdio::piped())
    .spawn()
    .expect("failed reverse command");

let cat = Command::new("cat")
    .arg("-")
    .stdin(reverse.stderr.unwrap()) // Converted into a Stdio here
    .output()
    .expect("failed echo command");

assert_eq!(
    String::from_utf8_lossy(&cat.stdout),
    "rev: cannot open non_existing_file.txt: No such file or directory\n"
);

impl IntoRawFd for ChildStderr

This is supported on Unix only.

fn into_raw_fd(self) -> RawFd

Consumes this object, returning the raw underlying file descriptor.

impl IntoRawHandle for ChildStderr

This is supported on Windows only.

fn into_raw_handle(self) -> RawHandle

Consumes this object, returning the raw underlying handle.

impl Read for ChildStderr

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.

fn is_read_vectored(&self) -> bool

🔬 This is a nightly-only experimental API. (can_vector #69941)

Determines if this Reader has an efficient read_vectored implementation.

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.

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

🔬 This is a nightly-only experimental API. (read_buf #78485)

Pull some bytes from this source into the specified buffer.

fn read_buf_exact(&mut self, buf: &mut ReadBuf<'_>) -> Result<()>

🔬 This is a nightly-only experimental API. (read_buf #78485)

Read the exact number of bytes required to fill buf.

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

Creates a “by reference” adaptor 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: Read>(self, next: R) -> Chain<Self, R> where
    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.