Function std::io::stdout

1.0.0 · source ·
pub fn stdout() -> Stdout 
Expand description

Constructs a new handle to the standard output of the current process.

Each handle returned is a reference to a shared global buffer whose access is synchronized via a mutex. If you need more explicit control over locking, see the Stdout::lock 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.

§Examples

Using implicit synchronization:

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

fn main() -> io::Result<()> {
    io::stdout().write_all(b"hello world")?;

    Ok(())
}

Using explicit synchronization:

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

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

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

    Ok(())
}