Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 982 insertions, 0 deletions

diff --git a/library/std/src/env.rs b/library/std/src/env.rs
new file mode 100644
index 000000000..463f71406
--- /dev/null
+++ b/library/std/src/env.rs
@@ -0,0 +1,982 @@
+//! Inspection and manipulation of the process's environment.
+//!
+//! This module contains functions to inspect various aspects such as
+//! environment variables, process arguments, the current directory, and various
+//! other important directories.
+//!
+//! There are several functions and structs in this module that have a
+//! counterpart ending in `os`. Those ending in `os` will return an [`OsString`]
+//! and those without will return a [`String`].
+
+#![stable(feature = "env", since = "1.0.0")]
+
+#[cfg(test)]
+mod tests;
+
+use crate::error::Error;
+use crate::ffi::{OsStr, OsString};
+use crate::fmt;
+use crate::io;
+use crate::path::{Path, PathBuf};
+use crate::sys;
+use crate::sys::os as os_imp;
+
+/// Returns the current working directory as a [`PathBuf`].
+///
+/// # Platform-specific behavior
+///
+/// This function [currently] corresponds to the `getcwd` function on Unix
+/// and the `GetCurrentDirectoryW` function on Windows.
+///
+/// [currently]: crate::io#platform-specific-behavior
+///
+/// # Errors
+///
+/// Returns an [`Err`] if the current working directory value is invalid.
+/// Possible cases:
+///
+/// * Current directory does not exist.
+/// * There are insufficient permissions to access the current directory.
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// fn main() -> std::io::Result<()> {
+///     let path = env::current_dir()?;
+///     println!("The current directory is {}", path.display());
+///     Ok(())
+/// }
+/// ```
+#[doc(alias = "pwd")]
+#[doc(alias = "getcwd")]
+#[doc(alias = "GetCurrentDirectory")]
+#[stable(feature = "env", since = "1.0.0")]
+pub fn current_dir() -> io::Result<PathBuf> {
+    os_imp::getcwd()
+}
+
+/// Changes the current working directory to the specified path.
+///
+/// # Platform-specific behavior
+///
+/// This function [currently] corresponds to the `chdir` function on Unix
+/// and the `SetCurrentDirectoryW` function on Windows.
+///
+/// Returns an [`Err`] if the operation fails.
+///
+/// [currently]: crate::io#platform-specific-behavior
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+/// use std::path::Path;
+///
+/// let root = Path::new("/");
+/// assert!(env::set_current_dir(&root).is_ok());
+/// println!("Successfully changed working directory to {}!", root.display());
+/// ```
+#[doc(alias = "chdir")]
+#[stable(feature = "env", since = "1.0.0")]
+pub fn set_current_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
+    os_imp::chdir(path.as_ref())
+}
+
+/// An iterator over a snapshot of the environment variables of this process.
+///
+/// This structure is created by [`env::vars()`]. See its documentation for more.
+///
+/// [`env::vars()`]: vars
+#[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 structure is created by [`env::vars_os()`]. See its documentation for more.
+///
+/// [`env::vars_os()`]: vars_os
+#[stable(feature = "env", since = "1.0.0")]
+pub struct VarsOs {
+    inner: os_imp::Env,
+}
+
+/// Returns an iterator of (variable, value) pairs of strings, for all the
+/// environment variables of the current process.
+///
+/// The returned iterator contains a snapshot of the process's environment
+/// variables at the time of this invocation. Modifications to environment
+/// variables afterwards will not be reflected in the returned iterator.
+///
+/// # Panics
+///
+/// While iterating, the returned iterator will panic if any key or value in the
+/// environment is not valid unicode. If this is not desired, consider using
+/// [`env::vars_os()`].
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// // We will iterate through the references to the element returned by
+/// // env::vars();
+/// for (key, value) in env::vars() {
+///     println!("{key}: {value}");
+/// }
+/// ```
+///
+/// [`env::vars_os()`]: vars_os
+#[must_use]
+#[stable(feature = "env", since = "1.0.0")]
+pub fn vars() -> Vars {
+    Vars { inner: vars_os() }
+}
+
+/// Returns an iterator of (variable, value) pairs of OS strings, for all the
+/// environment variables of the current process.
+///
+/// The returned iterator contains a snapshot of the process's environment
+/// variables at the time of this invocation. Modifications to environment
+/// variables afterwards will not be reflected in the returned iterator.
+///
+/// Note that the returned iterator will not check if the environment variables
+/// are valid Unicode. If you want to panic on invalid UTF-8,
+/// use the [`vars`] function instead.
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// // We will iterate through the references to the element returned by
+/// // env::vars_os();
+/// for (key, value) in env::vars_os() {
+///     println!("{key:?}: {value:?}");
+/// }
+/// ```
+#[must_use]
+#[stable(feature = "env", since = "1.0.0")]
+pub fn vars_os() -> VarsOs {
+    VarsOs { inner: os_imp::env() }
+}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl Iterator for Vars {
+    type Item = (String, String);
+    fn next(&mut self) -> Option<(String, String)> {
+        self.inner.next().map(|(a, b)| (a.into_string().unwrap(), b.into_string().unwrap()))
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.inner.size_hint()
+    }
+}
+
+#[stable(feature = "std_debug", since = "1.16.0")]
+impl fmt::Debug for Vars {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("Vars").finish_non_exhaustive()
+    }
+}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl Iterator for VarsOs {
+    type Item = (OsString, OsString);
+    fn next(&mut self) -> Option<(OsString, OsString)> {
+        self.inner.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.inner.size_hint()
+    }
+}
+
+#[stable(feature = "std_debug", since = "1.16.0")]
+impl fmt::Debug for VarsOs {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("VarOs").finish_non_exhaustive()
+    }
+}
+
+/// Fetches the environment variable `key` from the current process.
+///
+/// # Errors
+///
+/// This function will return an error if the environment variable isn't set.
+///
+/// This function may return an error if the environment variable's name contains
+/// the equal sign character (`=`) or the NUL character.
+///
+/// This function will return an error if the environment variable's value is
+/// not valid Unicode. If this is not desired, consider using [`var_os`].
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// let key = "HOME";
+/// match env::var(key) {
+///     Ok(val) => println!("{key}: {val:?}"),
+///     Err(e) => println!("couldn't interpret {key}: {e}"),
+/// }
+/// ```
+#[stable(feature = "env", since = "1.0.0")]
+pub fn var<K: AsRef<OsStr>>(key: K) -> Result<String, VarError> {
+    _var(key.as_ref())
+}
+
+fn _var(key: &OsStr) -> Result<String, VarError> {
+    match var_os(key) {
+        Some(s) => s.into_string().map_err(VarError::NotUnicode),
+        None => Err(VarError::NotPresent),
+    }
+}
+
+/// Fetches the environment variable `key` from the current process, returning
+/// [`None`] if the variable isn't set or there's another error.
+///
+/// Note that the method will not check if the environment variable
+/// is valid Unicode. If you want to have an error on invalid UTF-8,
+/// use the [`var`] function instead.
+///
+/// # Errors
+///
+/// This function returns an error if the environment variable isn't set.
+///
+/// This function may return an error if the environment variable's name contains
+/// the equal sign character (`=`) or the NUL character.
+///
+/// This function may return an error if the environment variable's value contains
+/// the NUL character.
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// let key = "HOME";
+/// match env::var_os(key) {
+///     Some(val) => println!("{key}: {val:?}"),
+///     None => println!("{key} is not defined in the environment.")
+/// }
+/// ```
+#[must_use]
+#[stable(feature = "env", since = "1.0.0")]
+pub fn var_os<K: AsRef<OsStr>>(key: K) -> Option<OsString> {
+    _var_os(key.as_ref())
+}
+
+fn _var_os(key: &OsStr) -> Option<OsString> {
+    os_imp::getenv(key)
+}
+
+/// The error type for operations interacting with environment variables.
+/// Possibly returned from [`env::var()`].
+///
+/// [`env::var()`]: var
+#[derive(Debug, PartialEq, Eq, Clone)]
+#[stable(feature = "env", since = "1.0.0")]
+pub enum VarError {
+    /// The specified environment variable was not present in the current
+    /// process's environment.
+    #[stable(feature = "env", since = "1.0.0")]
+    NotPresent,
+
+    /// The specified environment variable was found, but it did not contain
+    /// valid unicode data. The found data is returned as a payload of this
+    /// variant.
+    #[stable(feature = "env", since = "1.0.0")]
+    NotUnicode(#[stable(feature = "env", since = "1.0.0")] OsString),
+}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl fmt::Display for VarError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            VarError::NotPresent => write!(f, "environment variable not found"),
+            VarError::NotUnicode(ref s) => {
+                write!(f, "environment variable was not valid unicode: {:?}", s)
+            }
+        }
+    }
+}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl Error for VarError {
+    #[allow(deprecated)]
+    fn description(&self) -> &str {
+        match *self {
+            VarError::NotPresent => "environment variable not found",
+            VarError::NotUnicode(..) => "environment variable was not valid unicode",
+        }
+    }
+}
+
+/// Sets the environment variable `key` to the value `value` for the currently running
+/// process.
+///
+/// Note that while concurrent access to environment variables is safe in Rust,
+/// some platforms only expose inherently unsafe non-threadsafe APIs for
+/// inspecting the environment. As a result, extra care needs to be taken when
+/// auditing calls to unsafe external FFI functions to ensure that any external
+/// environment accesses are properly synchronized with accesses in Rust.
+///
+/// Discussion of this unsafety on Unix may be found in:
+///
+///  - [Austin Group Bugzilla](https://austingroupbugs.net/view.php?id=188)
+///  - [GNU C library Bugzilla](https://sourceware.org/bugzilla/show_bug.cgi?id=15607#c2)
+///
+/// # Panics
+///
+/// This function may panic if `key` is empty, contains an ASCII equals sign `'='`
+/// or the NUL character `'\0'`, or when `value` contains the NUL character.
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// let key = "KEY";
+/// env::set_var(key, "VALUE");
+/// assert_eq!(env::var(key), Ok("VALUE".to_string()));
+/// ```
+#[stable(feature = "env", since = "1.0.0")]
+pub fn set_var<K: AsRef<OsStr>, V: AsRef<OsStr>>(key: K, value: V) {
+    _set_var(key.as_ref(), value.as_ref())
+}
+
+fn _set_var(key: &OsStr, value: &OsStr) {
+    os_imp::setenv(key, value).unwrap_or_else(|e| {
+        panic!("failed to set environment variable `{key:?}` to `{value:?}`: {e}")
+    })
+}
+
+/// Removes an environment variable from the environment of the currently running process.
+///
+/// Note that while concurrent access to environment variables is safe in Rust,
+/// some platforms only expose inherently unsafe non-threadsafe APIs for
+/// inspecting the environment. As a result extra care needs to be taken when
+/// auditing calls to unsafe external FFI functions to ensure that any external
+/// environment accesses are properly synchronized with accesses in Rust.
+///
+/// Discussion of this unsafety on Unix may be found in:
+///
+///  - [Austin Group Bugzilla](https://austingroupbugs.net/view.php?id=188)
+///  - [GNU C library Bugzilla](https://sourceware.org/bugzilla/show_bug.cgi?id=15607#c2)
+///
+/// # Panics
+///
+/// This function may panic if `key` is empty, contains an ASCII equals sign
+/// `'='` or the NUL character `'\0'`, or when the value contains the NUL
+/// character.
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// let key = "KEY";
+/// env::set_var(key, "VALUE");
+/// assert_eq!(env::var(key), Ok("VALUE".to_string()));
+///
+/// env::remove_var(key);
+/// assert!(env::var(key).is_err());
+/// ```
+#[stable(feature = "env", since = "1.0.0")]
+pub fn remove_var<K: AsRef<OsStr>>(key: K) {
+    _remove_var(key.as_ref())
+}
+
+fn _remove_var(key: &OsStr) {
+    os_imp::unsetenv(key)
+        .unwrap_or_else(|e| panic!("failed to remove environment variable `{key:?}`: {e}"))
+}
+
+/// An iterator that splits an environment variable into paths according to
+/// platform-specific conventions.
+///
+/// The iterator element type is [`PathBuf`].
+///
+/// This structure is created by [`env::split_paths()`]. See its
+/// documentation for more.
+///
+/// [`env::split_paths()`]: split_paths
+#[must_use = "iterators are lazy and do nothing unless consumed"]
+#[stable(feature = "env", since = "1.0.0")]
+pub struct SplitPaths<'a> {
+    inner: os_imp::SplitPaths<'a>,
+}
+
+/// Parses input according to platform conventions for the `PATH`
+/// environment variable.
+///
+/// Returns an iterator over the paths contained in `unparsed`. The iterator
+/// element type is [`PathBuf`].
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// let key = "PATH";
+/// match env::var_os(key) {
+///     Some(paths) => {
+///         for path in env::split_paths(&paths) {
+///             println!("'{}'", path.display());
+///         }
+///     }
+///     None => println!("{key} is not defined in the environment.")
+/// }
+/// ```
+#[stable(feature = "env", since = "1.0.0")]
+pub fn split_paths<T: AsRef<OsStr> + ?Sized>(unparsed: &T) -> SplitPaths<'_> {
+    SplitPaths { inner: os_imp::split_paths(unparsed.as_ref()) }
+}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl<'a> Iterator for SplitPaths<'a> {
+    type Item = PathBuf;
+    fn next(&mut self) -> Option<PathBuf> {
+        self.inner.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.inner.size_hint()
+    }
+}
+
+#[stable(feature = "std_debug", since = "1.16.0")]
+impl fmt::Debug for SplitPaths<'_> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("SplitPaths").finish_non_exhaustive()
+    }
+}
+
+/// The error type for operations on the `PATH` variable. Possibly returned from
+/// [`env::join_paths()`].
+///
+/// [`env::join_paths()`]: join_paths
+#[derive(Debug)]
+#[stable(feature = "env", since = "1.0.0")]
+pub struct JoinPathsError {
+    inner: os_imp::JoinPathsError,
+}
+
+/// Joins a collection of [`Path`]s appropriately for the `PATH`
+/// environment variable.
+///
+/// # Errors
+///
+/// Returns an [`Err`] (containing an error message) if one of the input
+/// [`Path`]s contains an invalid character for constructing the `PATH`
+/// variable (a double quote on Windows or a colon on Unix).
+///
+/// # Examples
+///
+/// Joining paths on a Unix-like platform:
+///
+/// ```
+/// use std::env;
+/// use std::ffi::OsString;
+/// use std::path::Path;
+///
+/// fn main() -> Result<(), env::JoinPathsError> {
+/// # if cfg!(unix) {
+///     let paths = [Path::new("/bin"), Path::new("/usr/bin")];
+///     let path_os_string = env::join_paths(paths.iter())?;
+///     assert_eq!(path_os_string, OsString::from("/bin:/usr/bin"));
+/// # }
+///     Ok(())
+/// }
+/// ```
+///
+/// Joining a path containing a colon on a Unix-like platform results in an
+/// error:
+///
+/// ```
+/// # if cfg!(unix) {
+/// use std::env;
+/// use std::path::Path;
+///
+/// let paths = [Path::new("/bin"), Path::new("/usr/bi:n")];
+/// assert!(env::join_paths(paths.iter()).is_err());
+/// # }
+/// ```
+///
+/// Using `env::join_paths()` with [`env::split_paths()`] to append an item to
+/// the `PATH` environment variable:
+///
+/// ```
+/// use std::env;
+/// use std::path::PathBuf;
+///
+/// fn main() -> Result<(), env::JoinPathsError> {
+///     if let Some(path) = env::var_os("PATH") {
+///         let mut paths = env::split_paths(&path).collect::<Vec<_>>();
+///         paths.push(PathBuf::from("/home/xyz/bin"));
+///         let new_path = env::join_paths(paths)?;
+///         env::set_var("PATH", &new_path);
+///     }
+///
+///     Ok(())
+/// }
+/// ```
+///
+/// [`env::split_paths()`]: split_paths
+#[stable(feature = "env", since = "1.0.0")]
+pub fn join_paths<I, T>(paths: I) -> Result<OsString, JoinPathsError>
+where
+    I: IntoIterator<Item = T>,
+    T: AsRef<OsStr>,
+{
+    os_imp::join_paths(paths.into_iter()).map_err(|e| JoinPathsError { inner: e })
+}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl fmt::Display for JoinPathsError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.inner.fmt(f)
+    }
+}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl Error for JoinPathsError {
+    #[allow(deprecated, deprecated_in_future)]
+    fn description(&self) -> &str {
+        self.inner.description()
+    }
+}
+
+/// Returns the path of the current user's home directory if known.
+///
+/// # Unix
+///
+/// - Returns the value of the 'HOME' environment variable if it is set
+///   (including to an empty string).
+/// - Otherwise, it tries to determine the home directory by invoking the `getpwuid_r` function
+///   using the UID of the current user. An empty home directory field returned from the
+///   `getpwuid_r` function is considered to be a valid value.
+/// - Returns `None` if the current user has no entry in the /etc/passwd file.
+///
+/// # Windows
+///
+/// - Returns the value of the 'HOME' environment variable if it is set
+///   (including to an empty string).
+/// - Otherwise, returns the value of the 'USERPROFILE' environment variable if it is set
+///   (including to an empty string).
+/// - If both do not exist, [`GetUserProfileDirectory`][msdn] is used to return the path.
+///
+/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/userenv/nf-userenv-getuserprofiledirectorya
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// match env::home_dir() {
+///     Some(path) => println!("Your home directory, probably: {}", path.display()),
+///     None => println!("Impossible to get your home dir!"),
+/// }
+/// ```
+#[deprecated(
+    since = "1.29.0",
+    note = "This function's behavior is unexpected and probably not what you want. \
+            Consider using a crate from crates.io instead."
+)]
+#[must_use]
+#[stable(feature = "env", since = "1.0.0")]
+pub fn home_dir() -> Option<PathBuf> {
+    os_imp::home_dir()
+}
+
+/// Returns the path of a temporary directory.
+///
+/// The temporary directory may be shared among users, or between processes
+/// with different privileges; thus, the creation of any files or directories
+/// in the temporary directory must use a secure method to create a uniquely
+/// named file. Creating a file or directory with a fixed or predictable name
+/// may result in "insecure temporary file" security vulnerabilities. Consider
+/// using a crate that securely creates temporary files or directories.
+///
+/// # Platform-specific behavior
+///
+/// On Unix, returns the value of the `TMPDIR` environment variable if it is
+/// set, otherwise for non-Android it returns `/tmp`. If Android, since there
+/// is no global temporary folder (it is usually allocated per-app), it returns
+/// `/data/local/tmp`.
+/// On Windows, the behavior is equivalent to that of [`GetTempPath2`][GetTempPath2] /
+/// [`GetTempPath`][GetTempPath], which this function uses internally.
+/// Note that, this [may change in the future][changes].
+///
+/// [changes]: io#platform-specific-behavior
+/// [GetTempPath2]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-gettemppath2a
+/// [GetTempPath]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-gettemppatha
+///
+/// ```no_run
+/// use std::env;
+///
+/// fn main() {
+///     let dir = env::temp_dir();
+///     println!("Temporary directory: {}", dir.display());
+/// }
+/// ```
+#[must_use]
+#[stable(feature = "env", since = "1.0.0")]
+pub fn temp_dir() -> PathBuf {
+    os_imp::temp_dir()
+}
+
+/// Returns the full filesystem path of the current running executable.
+///
+/// # Platform-specific behavior
+///
+/// If the executable was invoked through a symbolic link, some platforms will
+/// return the path of the symbolic link and other platforms will return the
+/// path of the symbolic link’s target.
+///
+/// If the executable is renamed while it is running, platforms may return the
+/// path at the time it was loaded instead of the new path.
+///
+/// # Errors
+///
+/// Acquiring the path of the current executable is a platform-specific operation
+/// that can fail for a good number of reasons. Some errors can include, but not
+/// be limited to, filesystem operations failing or general syscall failures.
+///
+/// # Security
+///
+/// The output of this function should not be trusted for anything
+/// that might have security implications. Basically, if users can run
+/// the executable, they can change the output arbitrarily.
+///
+/// As an example, you can easily introduce a race condition. It goes
+/// like this:
+///
+/// 1. You get the path to the current executable using `current_exe()`, and
+///    store it in a variable.
+/// 2. Time passes. A malicious actor removes the current executable, and
+///    replaces it with a malicious one.
+/// 3. You then use the stored path to re-execute the current
+///    executable.
+///
+/// You expected to safely execute the current executable, but you're
+/// instead executing something completely different. The code you
+/// just executed run with your privileges.
+///
+/// This sort of behavior has been known to [lead to privilege escalation] when
+/// used incorrectly.
+///
+/// [lead to privilege escalation]: https://securityvulns.com/Wdocument183.html
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// match env::current_exe() {
+///     Ok(exe_path) => println!("Path of this executable is: {}",
+///                              exe_path.display()),
+///     Err(e) => println!("failed to get current exe path: {e}"),
+/// };
+/// ```
+#[stable(feature = "env", since = "1.0.0")]
+pub fn current_exe() -> io::Result<PathBuf> {
+    os_imp::current_exe()
+}
+
+/// An iterator over the arguments of a process, yielding a [`String`] value for
+/// each argument.
+///
+/// This struct is created by [`env::args()`]. See its documentation
+/// for more.
+///
+/// The first element is traditionally the path of the executable, but it can be
+/// set to arbitrary text, and might not even exist. This means this property
+/// should not be relied upon for security purposes.
+///
+/// [`env::args()`]: args
+#[must_use = "iterators are lazy and do nothing unless consumed"]
+#[stable(feature = "env", since = "1.0.0")]
+pub struct Args {
+    inner: ArgsOs,
+}
+
+/// An iterator over the arguments of a process, yielding an [`OsString`] value
+/// for each argument.
+///
+/// This struct is created by [`env::args_os()`]. See its documentation
+/// for more.
+///
+/// The first element is traditionally the path of the executable, but it can be
+/// set to arbitrary text, and might not even exist. This means this property
+/// should not be relied upon for security purposes.
+///
+/// [`env::args_os()`]: args_os
+#[must_use = "iterators are lazy and do nothing unless consumed"]
+#[stable(feature = "env", since = "1.0.0")]
+pub struct ArgsOs {
+    inner: sys::args::Args,
+}
+
+/// Returns the arguments that this program was started with (normally passed
+/// via the command line).
+///
+/// The first element is traditionally the path of the executable, but it can be
+/// set to arbitrary text, and might not even exist. This means this property should
+/// not be relied upon for security purposes.
+///
+/// On Unix systems the shell usually expands unquoted arguments with glob patterns
+/// (such as `*` and `?`). On Windows this is not done, and such arguments are
+/// passed as-is.
+///
+/// On glibc Linux systems, arguments are retrieved by placing a function in `.init_array`.
+/// glibc passes `argc`, `argv`, and `envp` to functions in `.init_array`, as a non-standard
+/// extension. This allows `std::env::args` to work even in a `cdylib` or `staticlib`, as it
+/// does on macOS and Windows.
+///
+/// # Panics
+///
+/// The returned iterator will panic during iteration if any argument to the
+/// process is not valid Unicode. If this is not desired,
+/// use the [`args_os`] function instead.
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// // Prints each argument on a separate line
+/// for argument in env::args() {
+///     println!("{argument}");
+/// }
+/// ```
+#[stable(feature = "env", since = "1.0.0")]
+pub fn args() -> Args {
+    Args { inner: args_os() }
+}
+
+/// Returns the arguments that this program was started with (normally passed
+/// via the command line).
+///
+/// The first element is traditionally the path of the executable, but it can be
+/// set to arbitrary text, and might not even exist. This means this property should
+/// not be relied upon for security purposes.
+///
+/// On Unix systems the shell usually expands unquoted arguments with glob patterns
+/// (such as `*` and `?`). On Windows this is not done, and such arguments are
+/// passed as-is.
+///
+/// On glibc Linux systems, arguments are retrieved by placing a function in `.init_array`.
+/// glibc passes `argc`, `argv`, and `envp` to functions in `.init_array`, as a non-standard
+/// extension. This allows `std::env::args_os` to work even in a `cdylib` or `staticlib`, as it
+/// does on macOS and Windows.
+///
+/// Note that the returned iterator will not check if the arguments to the
+/// process are valid Unicode. If you want to panic on invalid UTF-8,
+/// use the [`args`] function instead.
+///
+/// # Examples
+///
+/// ```
+/// use std::env;
+///
+/// // Prints each argument on a separate line
+/// for argument in env::args_os() {
+///     println!("{argument:?}");
+/// }
+/// ```
+#[stable(feature = "env", since = "1.0.0")]
+pub fn args_os() -> ArgsOs {
+    ArgsOs { inner: sys::args::args() }
+}
+
+#[stable(feature = "env_unimpl_send_sync", since = "1.26.0")]
+impl !Send for Args {}
+
+#[stable(feature = "env_unimpl_send_sync", since = "1.26.0")]
+impl !Sync for Args {}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl Iterator for Args {
+    type Item = String;
+    fn next(&mut self) -> Option<String> {
+        self.inner.next().map(|s| s.into_string().unwrap())
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.inner.size_hint()
+    }
+}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl ExactSizeIterator for Args {
+    fn len(&self) -> usize {
+        self.inner.len()
+    }
+    fn is_empty(&self) -> bool {
+        self.inner.is_empty()
+    }
+}
+
+#[stable(feature = "env_iterators", since = "1.12.0")]
+impl DoubleEndedIterator for Args {
+    fn next_back(&mut self) -> Option<String> {
+        self.inner.next_back().map(|s| s.into_string().unwrap())
+    }
+}
+
+#[stable(feature = "std_debug", since = "1.16.0")]
+impl fmt::Debug for Args {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("Args").field("inner", &self.inner.inner).finish()
+    }
+}
+
+#[stable(feature = "env_unimpl_send_sync", since = "1.26.0")]
+impl !Send for ArgsOs {}
+
+#[stable(feature = "env_unimpl_send_sync", since = "1.26.0")]
+impl !Sync for ArgsOs {}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl Iterator for ArgsOs {
+    type Item = OsString;
+    fn next(&mut self) -> Option<OsString> {
+        self.inner.next()
+    }
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.inner.size_hint()
+    }
+}
+
+#[stable(feature = "env", since = "1.0.0")]
+impl ExactSizeIterator for ArgsOs {
+    fn len(&self) -> usize {
+        self.inner.len()
+    }
+    fn is_empty(&self) -> bool {
+        self.inner.is_empty()
+    }
+}
+
+#[stable(feature = "env_iterators", since = "1.12.0")]
+impl DoubleEndedIterator for ArgsOs {
+    fn next_back(&mut self) -> Option<OsString> {
+        self.inner.next_back()
+    }
+}
+
+#[stable(feature = "std_debug", since = "1.16.0")]
+impl fmt::Debug for ArgsOs {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("ArgsOs").field("inner", &self.inner).finish()
+    }
+}
+
+/// Constants associated with the current target
+#[stable(feature = "env", since = "1.0.0")]
+pub mod consts {
+    use crate::sys::env::os;
+
+    /// A string describing the architecture of the CPU that is currently
+    /// in use.
+    ///
+    /// Some possible values:
+    ///
+    /// - x86
+    /// - x86_64
+    /// - arm
+    /// - aarch64
+    /// - m68k
+    /// - mips
+    /// - mips64
+    /// - powerpc
+    /// - powerpc64
+    /// - riscv64
+    /// - s390x
+    /// - sparc64
+    #[stable(feature = "env", since = "1.0.0")]
+    pub const ARCH: &str = env!("STD_ENV_ARCH");
+
+    /// The family of the operating system. Example value is `unix`.
+    ///
+    /// Some possible values:
+    ///
+    /// - unix
+    /// - windows
+    #[stable(feature = "env", since = "1.0.0")]
+    pub const FAMILY: &str = os::FAMILY;
+
+    /// A string describing the specific operating system in use.
+    /// Example value is `linux`.
+    ///
+    /// Some possible values:
+    ///
+    /// - linux
+    /// - macos
+    /// - ios
+    /// - freebsd
+    /// - dragonfly
+    /// - netbsd
+    /// - openbsd
+    /// - solaris
+    /// - android
+    /// - windows
+    #[stable(feature = "env", since = "1.0.0")]
+    pub const OS: &str = os::OS;
+
+    /// Specifies the filename prefix used for shared libraries on this
+    /// platform. Example value is `lib`.
+    ///
+    /// Some possible values:
+    ///
+    /// - lib
+    /// - `""` (an empty string)
+    #[stable(feature = "env", since = "1.0.0")]
+    pub const DLL_PREFIX: &str = os::DLL_PREFIX;
+
+    /// Specifies the filename suffix used for shared libraries on this
+    /// platform. Example value is `.so`.
+    ///
+    /// Some possible values:
+    ///
+    /// - .so
+    /// - .dylib
+    /// - .dll
+    #[stable(feature = "env", since = "1.0.0")]
+    pub const DLL_SUFFIX: &str = os::DLL_SUFFIX;
+
+    /// Specifies the file extension used for shared libraries on this
+    /// platform that goes after the dot. Example value is `so`.
+    ///
+    /// Some possible values:
+    ///
+    /// - so
+    /// - dylib
+    /// - dll
+    #[stable(feature = "env", since = "1.0.0")]
+    pub const DLL_EXTENSION: &str = os::DLL_EXTENSION;
+
+    /// Specifies the filename suffix used for executable binaries on this
+    /// platform. Example value is `.exe`.
+    ///
+    /// Some possible values:
+    ///
+    /// - .exe
+    /// - .nexe
+    /// - .pexe
+    /// - `""` (an empty string)
+    #[stable(feature = "env", since = "1.0.0")]
+    pub const EXE_SUFFIX: &str = os::EXE_SUFFIX;
+
+    /// Specifies the file extension, if any, used for executable binaries
+    /// on this platform. Example value is `exe`.
+    ///
+    /// Some possible values:
+    ///
+    /// - exe
+    /// - `""` (an empty string)
+    #[stable(feature = "env", since = "1.0.0")]
+    pub const EXE_EXTENSION: &str = os::EXE_EXTENSION;
+}