# Struct std::process::Stdio 1.0.0[−][src]

    pub struct Stdio(_);

Describes what to do with a standard I/O stream for a child process when passed to the `stdin`, `stdout`, and `stderr` methods of `Command`.

## Implementations

### `impl Stdio`[src]

#### `pub fn piped() -> Stdio`[src]

A new pipe should be arranged to connect the parent and child processes.

# Examples

With stdout:

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

    let output = Command::new("echo")
        .arg("Hello, world!")
        .stdout(Stdio::piped())
        .output()
        .expect("Failed to execute command");

    assert_eq!(String::from_utf8_lossy(&output.stdout), "Hello, world!\n");
    // Nothing echoed to console

Run

With stdin:

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

    let mut child = Command::new("rev")
        .stdin(Stdio::piped())
        .stdout(Stdio::piped())
        .spawn()
        .expect("Failed to spawn child process");

    {
        let stdin = child.stdin.as_mut().expect("Failed to open stdin");
        stdin.write_all("Hello, world!".as_bytes()).expect("Failed to write to stdin");
    }

    let output = child.wait_with_output().expect("Failed to read stdout");
    assert_eq!(String::from_utf8_lossy(&output.stdout), "!dlrow ,olleH");

Run

#### `pub fn inherit() -> Stdio`[src]

The child inherits from the corresponding parent descriptor.

# Examples

With stdout:

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

    let output = Command::new("echo")
        .arg("Hello, world!")
        .stdout(Stdio::inherit())
        .output()
        .expect("Failed to execute command");

    assert_eq!(String::from_utf8_lossy(&output.stdout), "");
    // "Hello, world!" echoed to console

Run

With stdin:

    use std::process::{Command, Stdio};
    use std::io::{self, Write};

    let output = Command::new("rev")
        .stdin(Stdio::inherit())
        .stdout(Stdio::piped())
        .output()
        .expect("Failed to execute command");

    print!("You piped in the reverse of: ");
    io::stdout().write_all(&output.stdout).unwrap();

Run

#### `pub fn null() -> Stdio`[src]

This stream will be ignored. This is the equivalent of attaching the stream to `/dev/null`.

# Examples

With stdout:

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

    let output = Command::new("echo")
        .arg("Hello, world!")
        .stdout(Stdio::null())
        .output()
        .expect("Failed to execute command");

    assert_eq!(String::from_utf8_lossy(&output.stdout), "");
    // Nothing echoed to console

Run

With stdin:

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

    let output = Command::new("rev")
        .stdin(Stdio::null())
        .stdout(Stdio::piped())
        .output()
        .expect("Failed to execute command");

    assert_eq!(String::from_utf8_lossy(&output.stdout), "");
    // Ignores any piped-in input

Run

## Trait Implementations

### `impl Debug for Stdio` 1.16.0[src]

#### `fn fmt(&self, f: &mut Formatter<'_>) -> Result`[src]

Formats the value using the given formatter. Read more

### `impl From<ChildStderr> for Stdio` 1.20.0[src]

#### `fn from(child: ChildStderr) -> Stdio`[src]

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"
    );

Run

### `impl From<ChildStdin> for Stdio` 1.20.0[src]

#### `fn from(child: ChildStdin) -> Stdio`[src]

Converts a `ChildStdin` into a `Stdio`

# Examples

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

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

    let reverse = Command::new("rev")
        .stdin(Stdio::piped())
        .spawn()
        .expect("failed reverse command");

    let _echo = Command::new("echo")
        .arg("Hello, world!")
        .stdout(reverse.stdin.unwrap()) // Converted into a Stdio here
        .output()
        .expect("failed echo command");

    // "!dlrow ,olleH" echoed to console

Run

### `impl From<ChildStdout> for Stdio` 1.20.0[src]

#### `fn from(child: ChildStdout) -> Stdio`[src]

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");

Run

### `impl From<File> for Stdio` 1.20.0[src]

#### `fn from(file: File) -> Stdio`[src]

Converts a `File` into a `Stdio`

# Examples

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

    use std::fs::File;
    use std::process::Command;

    // With the `foo.txt` file containing `Hello, world!"
    let file = File::open("foo.txt").unwrap();

    let reverse = Command::new("rev")
        .stdin(file)  // Implicit File conversion into a Stdio
        .output()
        .expect("failed reverse command");

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

Run

### `impl FromRawFd for Stdio` 1.2.0[src]

This is supported on Unix only.

#### `unsafe fn from_raw_fd(fd: RawFd) -> Stdio`[src]

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

### `impl FromRawHandle for Stdio` 1.2.0[src]

This is supported on Windows only.

#### `unsafe fn from_raw_handle(handle: RawHandle) -> Stdio`[src]

Constructs a new I/O object from the specified raw handle. Read more

## Auto Trait Implementations

### `impl RefUnwindSafe for Stdio`[src]

### `impl Send for Stdio`[src]

### `impl Sync for Stdio`[src]

### `impl Unpin for Stdio`[src]

### `impl UnwindSafe for Stdio`[src]

## Blanket Implementations

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `pub fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow(&self) -> &Tⓘ

### Notable 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`
`[src]

Immutably borrows from an owned value. Read more

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow_mut(&mut self) -> &mut Tⓘ

### Notable 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`
`[src]

Mutably borrows from an owned value. Read more

### `impl<T> From<T> for T`[src]

#### `pub fn from(t: T) -> T`[src]

Performs the conversion.

### `impl<T, U> Into<U> for T where
U: From<T>,` [src]

#### `pub fn into(self) -> U`[src]

Performs the conversion.

### `impl<T, U> TryFrom<U> for T where
U: Into<T>,` [src]

#### `type Error = Infallible`

The type returned in the event of a conversion error.

#### `pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

Performs the conversion.

### `impl<T, U> TryInto<U> for T where
U: TryFrom<T>,` [src]

#### `type Error = <U as TryFrom<T>>::Error`

The type returned in the event of a conversion error.

#### `pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`[src]

Performs the conversion.