Struct std::io::Stderr

1.0.0 · source ·

pub struct Stderr { /* private fields */ }

Expand description

A handle to the standard error stream of a process.

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

Note: Windows Portability Considerations

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.

In a process with a detached console, such as one using #![windows_subsystem = "windows"], or in a child process spawned from such a process, the contained handle will be null. In such cases, the standard library’s Read and Write will do nothing and silently succeed. All other I/O operations, via the standard library or via raw Windows API calls, will fail.

Implementations

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impl Stderr

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pub fn lock(&self) -> StderrLock<'static>iNotable traits for StderrLock<'_>impl Write for StderrLock<'_>

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

1.63.0 · source

impl AsFd for Stderr

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

Available on Unix only.

Borrows the file descriptor. Read more

1.63.0 · source

impl AsHandle for Stderr

Available on Windows only.

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

Borrows the handle. Read more

1.21.0 · source

impl AsRawFd for Stderr

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fn as_raw_fd(&self) -> RawFd

Available on Unix only.

Extracts the raw file descriptor. Read more

1.21.0 · source

impl AsRawHandle for Stderr

Available on Windows only.

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fn as_raw_handle(&self) -> RawHandle

Extracts the raw handle. Read more

1.16.0 · source

impl Debug for Stderr

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

Formats the value using the given formatter. Read more

1.48.0 · source

impl Write for &Stderr

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

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

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fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize>

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

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fn is_write_vectored(&self) -> bool

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

Determines if this Writer has an efficient write_vectored implementation. Read more

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fn flush(&mut self) -> Result<()>

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

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

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

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fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<()>

🔬 This is a nightly-only experimental API. (write_all_vectored #70436)

Attempts to write multiple buffers into this writer. Read more

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fn write_fmt(&mut self, args: Arguments<'_>) -> Result<()>

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

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

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

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impl Write for Stderr

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

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

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fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize>

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

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fn is_write_vectored(&self) -> bool

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

Determines if this Writer has an efficient write_vectored implementation. Read more

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fn flush(&mut self) -> Result<()>

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

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

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

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fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<()>

🔬 This is a nightly-only experimental API. (write_all_vectored #70436)

Attempts to write multiple buffers into this writer. Read more

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fn write_fmt(&mut self, args: Arguments<'_>) -> Result<()>

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

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

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