Auto merge of rust-lang#116057 - RalfJung:io-safety, r=Mark-Simulacrum

fix OS-specific I/O safety docs since the io_safety feature is stable

Looks like this text was forgotten to be updated when `io_safety` got stabilized: it still says "once the io_safety feature is stable".

Also adjust the wording a bit for how these docs relate to the general concept of I/O safety.

library/std/src/os/unix/io/mod.rs

@@ -6,7 +6,8 @@
 //!
 //! This module provides three types for representing file descriptors,
 //! with different ownership properties: raw, borrowed, and owned, which are
-//! analogous to types used for representing pointers. These types reflect the Unix version of [I/O safety].
+//! analogous to types used for representing pointers. These types reflect concepts of [I/O
+//! safety][io-safety] on Unix.
 //!
 //! | Type               | Analogous to |
 //! | ------------------ | ------------ |
@@ -17,8 +18,8 @@
 //! Like raw pointers, `RawFd` values are primitive values. And in new code,
 //! they should be considered unsafe to do I/O on (analogous to dereferencing
 //! them). Rust did not always provide this guidance, so existing code in the
-//! Rust ecosystem often doesn't mark `RawFd` usage as unsafe. Once the
-//! `io_safety` feature is stable, libraries will be encouraged to migrate,
+//! Rust ecosystem often doesn't mark `RawFd` usage as unsafe.
+//! Libraries are encouraged to migrate,
 //! either by adding `unsafe` to APIs that dereference `RawFd` values, or by
 //! using to `BorrowedFd` or `OwnedFd` instead.
 //!
@@ -54,6 +55,8 @@
 //! Like boxes, `OwnedFd` values conceptually own the resource they point to,
 //! and free (close) it when they are dropped.
 //!
+//! See the [`io` module docs][io-safety] for a general explanation of I/O safety.
+//!
 //! ## `/proc/self/mem` and similar OS features
 //!
 //! Some platforms have special files, such as `/proc/self/mem`, which
@@ -74,7 +77,7 @@
 //! necessary to use *sandboxing*, which is outside the scope of `std`.
 //!
 //! [`BorrowedFd<'a>`]: crate::os::unix::io::BorrowedFd
-//! [I/O safety]: crate::io#io-safety
+//! [io-safety]: crate::io#io-safety
 
 #![stable(feature = "rust1", since = "1.0.0")]
 

library/std/src/os/windows/io/mod.rs

@@ -6,7 +6,8 @@
 //!
 //! This module provides three types for representing raw handles and sockets
 //! with different ownership properties: raw, borrowed, and owned, which are
-//! analogous to types used for representing pointers. These types reflect the Windows version of [I/O safety].
+//! analogous to types used for representing pointers. These types reflect concepts of [I/O
+//! safety][io-safety] on Windows.
 //!
 //! | Type                   | Analogous to |
 //! | ---------------------- | ------------ |
@@ -23,8 +24,8 @@
 //! And in new code, they should be considered unsafe to do I/O on (analogous
 //! to dereferencing them). Rust did not always provide this guidance, so
 //! existing code in the Rust ecosystem often doesn't mark `RawHandle` and
-//! `RawSocket` usage as unsafe. Once the `io_safety` feature is stable,
-//! libraries will be encouraged to migrate, either by adding `unsafe` to APIs
+//! `RawSocket` usage as unsafe.
+//! Libraries are encouraged to migrate, either by adding `unsafe` to APIs
 //! that dereference `RawHandle` and `RawSocket` values, or by using to
 //! `BorrowedHandle`, `BorrowedSocket`, `OwnedHandle`, or `OwnedSocket`.
 //!
@@ -45,9 +46,11 @@
 //! Like boxes, `OwnedHandle` and `OwnedSocket` values conceptually own the
 //! resource they point to, and free (close) it when they are dropped.
 //!
+//! See the [`io` module docs][io-safety] for a general explanation of I/O safety.
+//!
 //! [`BorrowedHandle<'a>`]: crate::os::windows::io::BorrowedHandle
 //! [`BorrowedSocket<'a>`]: crate::os::windows::io::BorrowedSocket
-//! [I/O safety]: crate::io#io-safety
+//! [io-safety]: crate::io#io-safety
 
 #![stable(feature = "rust1", since = "1.0.0")]