# 1.0.0[−][src]Struct std::io::Stderr

    pub struct Stderr { /* fields omitted */ }

A handle to the standard error stream of a process.

For more information, see the `io::stderr` method.

### Note: Windows Portability Consideration

When operating in a console, the Windows implementation of this stream does not support non-UTF-8 byte sequences. Attempting to write bytes that are not valid UTF-8 will return an error.

## Methods

### `impl Stderr`[src]

####
ⓘImportant traits for StderrLock<'_>

### Important traits for StderrLock<'_>

`impl<'_> Write for StderrLock<'_>`
`pub fn lock(&self) -> StderrLock`[src]

Locks this handle to the standard error stream, returning a writable guard.

The lock is released when the returned lock goes out of scope. The returned guard also implements the `Write` trait for writing data.

# Examples

    use std::io::{self, Write};

    fn foo() -> io::Result<()> {
        let stderr = io::stderr();
        let mut handle = stderr.lock();

        handle.write_all(b"hello world")?;

        Ok(())
    }Run

## Trait Implementations

### `impl AsRawFd for Stderr` 1.21.0[src]

#### `fn as_raw_fd(&self) -> RawFd`[src]

This is supported on Unix only.

Extracts the raw file descriptor. Read more

### `impl AsRawHandle for Stderr` 1.21.0[src]

#### `fn as_raw_handle(&self) -> RawHandle`[src]

This is supported on Windows only.

Extracts the raw handle, without taking any ownership.

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

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

Formats the value using the given formatter. Read more

### `impl Write for Stderr`[src]

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

Write a buffer into this writer, returning how many bytes were written. Read more

#### `fn write_vectored(&mut self, bufs: &[IoSlice]) -> Result<usize>`[src]

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

#### `fn flush(&mut self) -> Result<()>`[src]

Flush this output stream, ensuring that all intermediately buffered contents reach their destination. Read more

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

Attempts to write an entire buffer into this writer. Read more

#### `fn write_fmt(&mut self, args: Arguments) -> Result<()>`[src]

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

####
ⓘImportant traits for &'_ mut F

### 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,` [src]

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

## Auto Trait Implementations

### `impl RefUnwindSafe for Stderr`

### `impl Send for Stderr`

### `impl Sync for Stderr`

### `impl Unpin for Stderr`

### `impl UnwindSafe for Stderr`

## Blanket Implementations

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

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

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

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

####
ⓘImportant traits for &'_ mut F

### 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 borrow(&self) -> &T`[src]

Immutably borrows from an owned value. Read more

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

####
ⓘImportant traits for &'_ mut F

### 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 borrow_mut(&mut self) -> &mut T`[src]

Mutably borrows from an owned value. Read more

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

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

Performs the conversion.

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

#### `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.

#### `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.

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

Performs the conversion.