Auto merge of #39108 - GuillaumeGomez:rollup, r=GuillaumeGomez

Rollup of 6 pull requests

- Successful merges: #38247, #39028, #39065, #39084, #39105, #39106
- Failed merges:

2 files changed, 69 insertions, 11 deletions

diff --git a/src/libstd/env.rs b/src/libstd/env.rs
index d843d97420a..ae83312ec94 100644
--- a/src/libstd/env.rs
+++ b/src/libstd/env.rs
@@ -10,7 +10,7 @@
 
 //! Inspection and manipulation of the process's environment.
 //!
-//! This module contains methods to inspect various aspects such as
+//! This module contains functions to inspect various aspects such as
 //! environment variables, process arguments, the current directory, and various
 //! other important directories.
 
@@ -68,15 +68,17 @@ pub fn set_current_dir<P: AsRef<Path>>(p: P) -> io::Result<()> {
 
 /// An iterator over a snapshot of the environment variables of this process.
 ///
-/// This iterator is created through `std::env::vars()` and yields `(String,
-/// String)` pairs.
+/// This structure is created through the [`std::env::vars`] function.
+///
+/// [`std::env::vars`]: fn.vars.html
 #[stable(feature = "env", since = "1.0.0")]
 pub struct Vars { inner: VarsOs }
 
 /// An iterator over a snapshot of the environment variables of this process.
 ///
-/// This iterator is created through `std::env::vars_os()` and yields
-/// `(OsString, OsString)` pairs.
+/// This structure is created through the [`std::env::vars_os`] function.
+///
+/// [`std::env::vars_os`]: fn.vars_os.html
 #[stable(feature = "env", since = "1.0.0")]
 pub struct VarsOs { inner: os_imp::Env }
 
@@ -218,7 +220,9 @@ fn _var_os(key: &OsStr) -> Option<OsString> {
     })
 }
 
-/// Possible errors from the `env::var` method.
+/// Possible errors from the [`env::var`] function.
+///
+/// [env::var]: fn.var.html
 #[derive(Debug, PartialEq, Eq, Clone)]
 #[stable(feature = "env", since = "1.0.0")]
 pub enum VarError {
@@ -570,7 +574,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
 /// An iterator over the arguments of a process, yielding a [`String`] value
 /// for each argument.
 ///
-/// This structure is created through the [`std::env::args`] method.
+/// This structure is created through the [`std::env::args`] function.
 ///
 /// [`String`]: ../string/struct.String.html
 /// [`std::env::args`]: ./fn.args.html
@@ -580,7 +584,7 @@ pub struct Args { inner: ArgsOs }
 /// An iterator over the arguments of a process, yielding an [`OsString`] value
 /// for each argument.
 ///
-/// This structure is created through the [`std::env::args_os`] method.
+/// This structure is created through the [`std::env::args_os`] function.
 ///
 /// [`OsString`]: ../ffi/struct.OsString.html
 /// [`std::env::args_os`]: ./fn.args_os.html
diff --git a/src/libstd/sys/unix/ext/ffi.rs b/src/libstd/sys/unix/ext/ffi.rs
index d59b4fc0b70..fb9984ccbdd 100644
--- a/src/libstd/sys/unix/ext/ffi.rs
+++ b/src/libstd/sys/unix/ext/ffi.rs
@@ -20,11 +20,38 @@ use sys_common::{FromInner, IntoInner, AsInner};
 /// Unix-specific extensions to `OsString`.
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait OsStringExt {
-    /// Creates an `OsString` from a byte vector.
+    /// Creates an [`OsString`] from a byte vector.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::ffi::OsString;
+    /// use std::os::unix::ffi::OsStringExt;
+    ///
+    /// let bytes = b"foo".to_vec();
+    /// let os_string = OsString::from_vec(bytes);
+    /// assert_eq!(os_string.to_str(), Some("foo"));
+    /// ```
+    ///
+    /// [`OsString`]: ../../../ffi/struct.OsString.html
     #[stable(feature = "rust1", since = "1.0.0")]
     fn from_vec(vec: Vec<u8>) -> Self;
 
-    /// Yields the underlying byte vector of this `OsString`.
+    /// Yields the underlying byte vector of this [`OsString`].
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::ffi::OsString;
+    /// use std::os::unix::ffi::OsStringExt;
+    ///
+    /// let mut os_string = OsString::new();
+    /// os_string.push("foo");
+    /// let bytes = os_string.into_vec();
+    /// assert_eq!(bytes, b"foo");
+    /// ```
+    ///
+    /// [`OsString`]: ../../../ffi/struct.OsString.html
     #[stable(feature = "rust1", since = "1.0.0")]
     fn into_vec(self) -> Vec<u8>;
 }
@@ -43,9 +70,36 @@ impl OsStringExt for OsString {
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait OsStrExt {
     #[stable(feature = "rust1", since = "1.0.0")]
+    /// Creates an [`OsStr`] from a byte slice.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::ffi::OsStr;
+    /// use std::os::unix::ffi::OsStrExt;
+    ///
+    /// let bytes = b"foo";
+    /// let os_str = OsStr::from_bytes(bytes);
+    /// assert_eq!(os_str.to_str(), Some("foo"));
+    /// ```
+    ///
+    /// [`OsStr`]: ../../../ffi/struct.OsStr.html
     fn from_bytes(slice: &[u8]) -> &Self;
 
-    /// Gets the underlying byte view of the `OsStr` slice.
+    /// Gets the underlying byte view of the [`OsStr`] slice.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::ffi::OsStr;
+    /// use std::os::unix::ffi::OsStrExt;
+    ///
+    /// let mut os_str = OsStr::new("foo");
+    /// let bytes = os_str.as_bytes();
+    /// assert_eq!(bytes, b"foo");
+    /// ```
+    ///
+    /// [`OsStr`]: ../../../ffi/struct.OsStr.html
     #[stable(feature = "rust1", since = "1.0.0")]
     fn as_bytes(&self) -> &[u8];
 }