std: Implement stdio for `std::io`

This is an implementation of RFC 899 and adds stdio functionality to the new
`std::io` module. Details of the API can be found on the RFC, but from a high
level:

* `io::{stdin, stdout, stderr}` constructors are now available. There are also
  `*_raw` variants for unbuffered and unlocked access.
* All handles are globally shared (excluding raw variants).
* The stderr handle is no longer buffered.
* All handles can be explicitly locked (excluding the raw variants).

The `print!` and `println!` machinery has not yet been hooked up to these
streams just yet. The `std::fmt::output` module has also not yet been
implemented as part of this commit.

1 files changed, 4 insertions, 4 deletions

diff --git a/src/libstd/old_io/stdio.rs b/src/libstd/old_io/stdio.rs
index 56a707c24a6..a5df21749e2 100644
--- a/src/libstd/old_io/stdio.rs
+++ b/src/libstd/old_io/stdio.rs
@@ -224,10 +224,10 @@ pub fn stdin() -> StdinReader {
 
     unsafe {
         ONCE.call_once(|| {
-            // The default buffer capacity is 64k, but apparently windows doesn't like
-            // 64k reads on stdin. See #13304 for details, but the idea is that on
-            // windows we use a slightly smaller buffer that's been seen to be
-            // acceptable.
+            // The default buffer capacity is 64k, but apparently windows
+            // doesn't like 64k reads on stdin. See #13304 for details, but the
+            // idea is that on windows we use a slightly smaller buffer that's
+            // been seen to be acceptable.
             let stdin = if cfg!(windows) {
                 BufferedReader::with_capacity(8 * 1024, stdin_raw())
             } else {