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pub struct Child {
    pub stdin: Option<ChildStdin>,
    pub stdout: Option<ChildStdout>,
    pub stderr: Option<ChildStderr>,
    /* private fields */
}
Expand description

A spawned child process.

The process can be in running or exited state. Use status() or output() to wait for it to exit.

If the Child is dropped, the process keeps running in the background.

Examples

Spawn a process and wait for it to complete:

use async_process::Command;

Command::new("cp").arg("a.txt").arg("b.txt").status().await?;

Fields

stdin: Option<ChildStdin>

The handle for writing to the child’s standard input (stdin), if it has been captured.

stdout: Option<ChildStdout>

The handle for reading from the child’s standard output (stdout), if it has been captured.

stderr: Option<ChildStderr>

The handle for reading from the child’s standard error (stderr), if it has been captured.

Implementations

Returns the OS-assigned process identifier associated with this child.

Examples
use async_process::Command;

let mut child = Command::new("ls").spawn()?;
println!("id: {}", child.id());

Forces the child process to exit.

If the child has already exited, an InvalidInput error is returned.

This is equivalent to sending a SIGKILL on Unix platforms.

Examples
use async_process::Command;

let mut child = Command::new("yes").spawn()?;
child.kill()?;
println!("exit status: {}", child.status().await?);

Returns the exit status if the process has exited.

Unlike status(), this method will not drop the stdin handle.

Examples
use async_process::Command;

let mut child = Command::new("ls").spawn()?;

match child.try_status()? {
    None => println!("still running"),
    Some(status) => println!("exited with: {}", status),
}

Drops the stdin handle and waits for the process to exit.

Closing the stdin of the process helps avoid deadlocks. It ensures that the process does not block waiting for input from the parent process while the parent waits for the child to exit.

Examples
use async_process::{Command, Stdio};

let mut child = Command::new("cp")
    .arg("a.txt")
    .arg("b.txt")
    .spawn()?;

println!("exit status: {}", child.status().await?);

Drops the stdin handle and collects the output of the process.

Closing the stdin of the process helps avoid deadlocks. It ensures that the process does not block waiting for input from the parent process while the parent waits for the child to exit.

In order to capture the output of the process, Command::stdout() and Command::stderr() must be configured with Stdio::piped().

Examples
use async_process::{Command, Stdio};

let child = Command::new("ls")
    .stdout(Stdio::piped())
    .stderr(Stdio::piped())
    .spawn()?;

let out = child.output().await?;

Trait Implementations

Formats the value using the given formatter. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.