pub struct SharedWriter { /* private fields */ }Expand description
Clonable object that implements Write and
[AsyncWrite][futures::io::AsyncWrite] and allows for sending data to the
terminal without messing up the readline.
A SharedWriter instance is obtained by calling Readline::new(), which
also returns a Readline instance associated with the writer.
Data written to a SharedWriter is only output when a line feed ('\n')
has been written and either Readline::readline() or
Readline::flush() is executing on the associated Readline instance.
Trait Implementations§
Source§fn poll_write(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<Result<usize>>
fn poll_write( self: Pin<&mut Self>, cx: &mut Context<'_>, buf: &[u8], ) -> Poll<Result<usize>>
buf into the object. Read moreSource§fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>>
fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>>
Source§fn write(&mut self, buf: &[u8]) -> Result<usize>
fn write(&mut self, buf: &[u8]) -> Result<usize>
Source§fn flush(&mut self) -> Result<()>
fn flush(&mut self) -> Result<()>
Source§fn is_write_vectored(&self) -> bool
fn is_write_vectored(&self) -> bool
can_vector)1.0.0 · Source§fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>
fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>
Source§fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>
fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>
write_all_vectored)Auto Trait Implementations§
Blanket Implementations§
Source§impl<W> AsyncWriteExt for Wwhere
W: AsyncWrite + ?Sized,
impl<W> AsyncWriteExt for Wwhere
W: AsyncWrite + ?Sized,
Source§fn flush(&mut self) -> Flush<'_, Self>where
Self: Unpin,
fn flush(&mut self) -> Flush<'_, Self>where
Self: Unpin,
AsyncWrite. Read moreSource§fn close(&mut self) -> Close<'_, Self>where
Self: Unpin,
fn close(&mut self) -> Close<'_, Self>where
Self: Unpin,
AsyncWrite.Source§fn write<'a>(&'a mut self, buf: &'a [u8]) -> Write<'a, Self>where
Self: Unpin,
fn write<'a>(&'a mut self, buf: &'a [u8]) -> Write<'a, Self>where
Self: Unpin,
buf into the object. Read moreSource§fn write_vectored<'a>(
&'a mut self,
bufs: &'a [IoSlice<'a>],
) -> WriteVectored<'a, Self>where
Self: Unpin,
fn write_vectored<'a>(
&'a mut self,
bufs: &'a [IoSlice<'a>],
) -> WriteVectored<'a, Self>where
Self: Unpin,
bufs into the object using vectored
IO operations. Read moreSource§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
Source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
Source§impl<T> ExecutableCommand for T
impl<T> ExecutableCommand for T
Source§fn execute(&mut self, command: impl Command) -> Result<&mut T, Error>
fn execute(&mut self, command: impl Command) -> Result<&mut T, Error>
Executes the given command directly.
The given command its ANSI escape code will be written and flushed onto Self.
§Arguments
-
The command that you want to execute directly.
§Example
use std::io;
use crossterm::{ExecutableCommand, style::Print};
fn main() -> io::Result<()> {
// will be executed directly
io::stdout()
.execute(Print("sum:\n".to_string()))?
.execute(Print(format!("1 + 1= {} ", 1 + 1)))?;
Ok(())
// ==== Output ====
// sum:
// 1 + 1 = 2
}Have a look over at the Command API for more details.
§Notes
- In the case of UNIX and Windows 10, ANSI codes are written to the given ‘writer’.
- In case of Windows versions lower than 10, a direct WinAPI call will be made.
The reason for this is that Windows versions lower than 10 do not support ANSI codes,
and can therefore not be written to the given
writer. Therefore, there is no difference between execute and queue for those old Windows versions.
Source§impl<T> QueueableCommand for T
impl<T> QueueableCommand for T
Source§fn queue(&mut self, command: impl Command) -> Result<&mut T, Error>
fn queue(&mut self, command: impl Command) -> Result<&mut T, Error>
Queues the given command for further execution.
Queued commands will be executed in the following cases:
- When
flushis called manually on the given type implementingio::Write. - The terminal will
flushautomatically if the buffer is full. - Each line is flushed in case of
stdout, because it is line buffered.
§Arguments
-
The command that you want to queue for later execution.
§Examples
use std::io::{self, Write};
use crossterm::{QueueableCommand, style::Print};
fn main() -> io::Result<()> {
let mut stdout = io::stdout();
// `Print` will executed executed when `flush` is called.
stdout
.queue(Print("foo 1\n".to_string()))?
.queue(Print("foo 2".to_string()))?;
// some other code (no execution happening here) ...
// when calling `flush` on `stdout`, all commands will be written to the stdout and therefore executed.
stdout.flush()?;
Ok(())
// ==== Output ====
// foo 1
// foo 2
}Have a look over at the Command API for more details.
§Notes
- In the case of UNIX and Windows 10, ANSI codes are written to the given ‘writer’.
- In case of Windows versions lower than 10, a direct WinAPI call will be made.
The reason for this is that Windows versions lower than 10 do not support ANSI codes,
and can therefore not be written to the given
writer. Therefore, there is no difference between execute and queue for those old Windows versions.
Source§impl<W> SynchronizedUpdate for W
impl<W> SynchronizedUpdate for W
Source§fn sync_update<T>(
&mut self,
operations: impl FnOnce(&mut W) -> T,
) -> Result<T, Error>
fn sync_update<T>( &mut self, operations: impl FnOnce(&mut W) -> T, ) -> Result<T, Error>
Performs a set of actions within a synchronous update.
Updates will be suspended in the terminal, the function will be executed against self, updates will be resumed, and a flush will be performed.
§Arguments
-
Function
A function that performs the operations that must execute in a synchronized update.
§Examples
use std::io;
use crossterm::{ExecutableCommand, SynchronizedUpdate, style::Print};
fn main() -> io::Result<()> {
let mut stdout = io::stdout();
stdout.sync_update(|stdout| {
stdout.execute(Print("foo 1\n".to_string()))?;
stdout.execute(Print("foo 2".to_string()))?;
// The effects of the print command will not be present in the terminal
// buffer, but not visible in the terminal.
std::io::Result::Ok(())
})?;
// The effects of the commands will be visible.
Ok(())
// ==== Output ====
// foo 1
// foo 2
}§Notes
This command is performed only using ANSI codes, and will do nothing on terminals that do not support ANSI codes, or this specific extension.
When rendering the screen of the terminal, the Emulator usually iterates through each visible grid cell and renders its current state. With applications updating the screen a at higher frequency this can cause tearing.
This mode attempts to mitigate that.
When the synchronization mode is enabled following render calls will keep rendering the last rendered state. The terminal Emulator keeps processing incoming text and sequences. When the synchronized update mode is disabled again the renderer may fetch the latest screen buffer state again, effectively avoiding the tearing effect by unintentionally rendering in the middle a of an application screen update.