Trait sgx_tstd::io::Write [−][src]
pub trait Write { fn write(&mut self, buf: &[u8]) -> Result<usize>; fn flush(&mut self) -> Result<()>; fn write_all(&mut self, buf: &[u8]) -> Result<()> { ... } fn write_fmt(&mut self, fmt: Arguments) -> Result<()> { ... } fn by_ref(&mut self) -> &mut Self
where
Self: Sized, { ... } }
A trait for objects which are byte-oriented sinks.
Implementors of the Write
trait are sometimes called 'writers'.
Writers are defined by two required methods, write
and flush
:
-
The
write
method will attempt to write some data into the object, returning how many bytes were successfully written. -
The
flush
method is useful for adaptors and explicit buffers themselves for ensuring that all buffered data has been pushed out to the 'true sink'.
Writers are intended to be composable with one another. Many implementors
throughout std::io
take and provide types which implement the Write
trait.
Required Methods
fn write(&mut self, buf: &[u8]) -> Result<usize>
Write a buffer into this object, returning how many bytes were written.
This function will attempt to write the entire contents of buf
, but
the entire write may not succeed, or the write may also generate an
error. A call to write
represents at most one attempt to write to
any wrapped object.
Calls to write
are not guaranteed to block waiting for data to be
written, and a write which would otherwise block can be indicated through
an Err
variant.
If the return value is Ok(n)
then it must be guaranteed that
0 <= n <= buf.len()
. A return value of 0
typically means that the
underlying object is no longer able to accept bytes and will likely not
be able to in the future as well, or that the buffer provided is empty.
Errors
Each call to write
may generate an I/O error indicating that the
operation could not be completed. If an error is returned then no bytes
in the buffer were written to this writer.
It is not considered an error if the entire buffer could not be written to this writer.
An error of the ErrorKind::Interrupted
kind is non-fatal and the
write operation should be retried if there is nothing else to do.
fn flush(&mut self) -> Result<()>
Flush this output stream, ensuring that all intermediately buffered contents reach their destination.
Errors
It is considered an error if not all bytes could be written due to I/O errors or EOF being reached.
Provided Methods
fn write_all(&mut self, buf: &[u8]) -> Result<()>
Attempts to write an entire buffer into this write.
This method will continuously call write
until there is no more data
to be written or an error of non-ErrorKind::Interrupted
kind is
returned. This method will not return until the entire buffer has been
successfully written or such an error occurs. The first error that is
not of ErrorKind::Interrupted
kind generated from this method will be
returned.
Errors
This function will return the first error of
non-ErrorKind::Interrupted
kind that write
returns.
fn write_fmt(&mut self, fmt: Arguments) -> Result<()>
Writes a formatted string into this writer, returning any error encountered.
This method is primarily used to interface with the
format_args!
macro, but it is rare that this should
explicitly be called. The write!
macro should be favored to
invoke this method instead.
This function internally uses the write_all
method on
this trait and hence will continuously write data so long as no errors
are received. This also means that partial writes are not indicated in
this signature.
Errors
This function will return any I/O error reported while formatting.
fn by_ref(&mut self) -> &mut Self where
Self: Sized,
Self: Sized,
Creates a "by reference" adaptor for this instance of Write
.
The returned adaptor also implements Write
and will simply borrow this
current writer.
Implementors
impl Write for SgxFile
impl<'a> Write for &'a SgxFile
impl<W: Write> Write for BufWriter<W>
impl<W: Write> Write for LineWriter<W>
impl<'a> Write for Cursor<&'a mut [u8]>
impl<'a> Write for Cursor<&'a mut Vec<u8>>
impl Write for Cursor<Vec<u8>>
impl Write for Cursor<Box<[u8]>>
impl<'a, W: Write + ?Sized> Write for &'a mut W
impl<W: Write + ?Sized> Write for Box<W>
impl<'a> Write for &'a mut [u8]
impl Write for Vec<u8>
impl Write for Sink
impl Write for Stdout
impl<'a> Write for StdoutLock<'a>
impl Write for Stderr
impl<'a> Write for StderrLock<'a>
impl Write for File
impl<'a> Write for &'a File