pub struct Stdin { /* private fields */ }
Expand description
A handle to the standard input stream of a process.
Each handle is a shared reference to a global buffer of input data to this
process. A handle can be lock
’d to gain full access to BufRead
methods
(e.g., .lines()
). Reads to this handle are otherwise locked with respect
to other reads.
This handle implements the Read
trait, but beware that concurrent reads
of Stdin
must be executed with care.
Created by the io::stdin
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 read 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
use std::io;
fn main() -> io::Result<()> {
let mut buffer = String::new();
let stdin = io::stdin(); // We get `Stdin` here.
stdin.read_line(&mut buffer)?;
Ok(())
}
RunImplementations
sourceimpl Stdin
impl Stdin
sourcepub fn lock(&self) -> StdinLock<'static>ⓘNotable traits for StdinLock<'_>impl Read for StdinLock<'_>
pub fn lock(&self) -> StdinLock<'static>ⓘNotable traits for StdinLock<'_>impl Read for StdinLock<'_>
Locks this handle to the standard input stream, returning a readable guard.
The lock is released when the returned lock goes out of scope. The
returned guard also implements the Read
and BufRead
traits for
accessing the underlying data.
Examples
use std::io::{self, BufRead};
fn main() -> io::Result<()> {
let mut buffer = String::new();
let stdin = io::stdin();
let mut handle = stdin.lock();
handle.read_line(&mut buffer)?;
Ok(())
}
Runsourcepub fn read_line(&self, buf: &mut String) -> Result<usize>
pub fn read_line(&self, buf: &mut String) -> Result<usize>
Locks this handle and reads a line of input, appending it to the specified buffer.
For detailed semantics of this method, see the documentation on
BufRead::read_line
.
Examples
use std::io;
let mut input = String::new();
match io::stdin().read_line(&mut input) {
Ok(n) => {
println!("{n} bytes read");
println!("{input}");
}
Err(error) => println!("error: {error}"),
}
RunYou can run the example one of two ways:
- Pipe some text to it, e.g.,
printf foo | path/to/executable
- Give it text interactively by running the executable directly, in which case it will wait for the Enter key to be pressed before continuing
1.62.0 · sourcepub fn lines(self) -> Lines<StdinLock<'static>>ⓘNotable traits for Lines<B>impl<B: BufRead> Iterator for Lines<B> type Item = Result<String>;
pub fn lines(self) -> Lines<StdinLock<'static>>ⓘNotable traits for Lines<B>impl<B: BufRead> Iterator for Lines<B> type Item = Result<String>;
Consumes this handle and returns an iterator over input lines.
For detailed semantics of this method, see the documentation on
BufRead::lines
.
Examples
use std::io;
let lines = io::stdin().lines();
for line in lines {
println!("got a line: {}", line.unwrap());
}
RunTrait Implementations
1.63.0 · sourceimpl AsFd for Stdin
impl AsFd for Stdin
sourcefn as_fd(&self) -> BorrowedFd<'_>
fn as_fd(&self) -> BorrowedFd<'_>
1.63.0 · sourceimpl AsHandle for Stdin
Available on Windows only.
impl AsHandle for Stdin
sourcefn as_handle(&self) -> BorrowedHandle<'_>
fn as_handle(&self) -> BorrowedHandle<'_>
1.21.0 · sourceimpl AsRawHandle for Stdin
Available on Windows only.
impl AsRawHandle for Stdin
sourcefn as_raw_handle(&self) -> RawHandle
fn as_raw_handle(&self) -> RawHandle
sourceimpl Read for Stdin
impl Read for Stdin
sourcefn read(&mut self, buf: &mut [u8]) -> Result<usize>
fn read(&mut self, buf: &mut [u8]) -> Result<usize>
sourcefn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize>
fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize>
read
, except that it reads into a slice of buffers. Read moresourcefn is_read_vectored(&self) -> bool
fn is_read_vectored(&self) -> bool
can_vector
#69941)sourcefn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize>
fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize>
buf
. Read moresourcefn read_to_string(&mut self, buf: &mut String) -> Result<usize>
fn read_to_string(&mut self, buf: &mut String) -> Result<usize>
buf
. Read moresourcefn read_exact(&mut self, buf: &mut [u8]) -> Result<()>
fn read_exact(&mut self, buf: &mut [u8]) -> Result<()>
buf
. Read moresourcefn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<()>
fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<()>
read_buf
#78485)sourcefn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<()>
fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<()>
read_buf
#78485)cursor
. Read moresourcefn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
Read
. Read more