library/std/src/os/unix/process.rs - toolchain/rustc - Git at Google

 //! Unix-specific extensions to primitives in the `std::process` module.

 #![stable(feature = "rust1", since = "1.0.0")]

 use crate::ffi::OsStr;
 use crate::io;
 use crate::os::unix::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, OwnedFd, RawFd};
 use crate::process;
 use crate::sealed::Sealed;
 use crate::sys;
 use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner};

 /// Unix-specific extensions to the [`process::Command`] builder.
 ///
 /// This trait is sealed: it cannot be implemented outside the standard library.
 /// This is so that future additional methods are not breaking changes.
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait CommandExt: Sealed {
     /// Sets the child process's user ID. This translates to a
     /// `setuid` call in the child process. Failure in the `setuid`
     /// call will cause the spawn to fail.
     #[stable(feature = "rust1", since = "1.0.0")]
     fn uid(
         &mut self,
         #[cfg(not(target_os = "vxworks"))] id: u32,
         #[cfg(target_os = "vxworks")] id: u16,
     ) -> &mut process::Command;

     /// Similar to `uid`, but sets the group ID of the child process. This has
     /// the same semantics as the `uid` field.
     #[stable(feature = "rust1", since = "1.0.0")]
     fn gid(
         &mut self,
         #[cfg(not(target_os = "vxworks"))] id: u32,
         #[cfg(target_os = "vxworks")] id: u16,
     ) -> &mut process::Command;

     /// Sets the supplementary group IDs for the calling process. Translates to
     /// a `setgroups` call in the child process.
     #[unstable(feature = "setgroups", issue = "38527", reason = "")]
     fn groups(
         &mut self,
         #[cfg(not(target_os = "vxworks"))] groups: &[u32],
         #[cfg(target_os = "vxworks")] groups: &[u16],
     ) -> &mut process::Command;

     /// Schedules a closure to be run just before the `exec` function is
     /// invoked.
     ///
     /// The closure is allowed to return an I/O error whose OS error code will
     /// be communicated back to the parent and returned as an error from when
     /// the spawn was requested.
     ///
     /// Multiple closures can be registered and they will be called in order of
     /// their registration. If a closure returns `Err` then no further closures
     /// will be called and the spawn operation will immediately return with a
     /// failure.
     ///
     /// # Notes and Safety
     ///
     /// This closure will be run in the context of the child process after a
     /// `fork`. This primarily means that any modifications made to memory on
     /// behalf of this closure will **not** be visible to the parent process.
     /// This is often a very constrained environment where normal operations
     /// like `malloc`, accessing environment variables through [`std::env`]
     /// or acquiring a mutex are not guaranteed to work (due to
     /// other threads perhaps still running when the `fork` was run).
     ///
     /// For further details refer to the [POSIX fork() specification]
     /// and the equivalent documentation for any targeted
     /// platform, especially the requirements around *async-signal-safety*.
     ///
     /// This also means that all resources such as file descriptors and
     /// memory-mapped regions got duplicated. It is your responsibility to make
     /// sure that the closure does not violate library invariants by making
     /// invalid use of these duplicates.
     ///
     /// Panicking in the closure is safe only if all the format arguments for the
     /// panic message can be safely formatted; this is because although
     /// `Command` calls [`std::panic::always_abort`](crate::panic::always_abort)
     /// before calling the pre_exec hook, panic will still try to format the
     /// panic message.
     ///
     /// When this closure is run, aspects such as the stdio file descriptors and
     /// working directory have successfully been changed, so output to these
     /// locations might not appear where intended.
     ///
     /// [POSIX fork() specification]:
     ///     https://pubs.opengroup.org/onlinepubs/9699919799/functions/fork.html
     /// [`std::env`]: mod@crate::env
     #[stable(feature = "process_pre_exec", since = "1.34.0")]
     unsafe fn pre_exec<F>(&mut self, f: F) -> &mut process::Command
     where
         F: FnMut() -> io::Result<()> + Send + Sync + 'static;

     /// Schedules a closure to be run just before the `exec` function is
     /// invoked.
     ///
     /// This method is stable and usable, but it should be unsafe. To fix
     /// that, it got deprecated in favor of the unsafe [`pre_exec`].
     ///
     /// [`pre_exec`]: CommandExt::pre_exec
     #[stable(feature = "process_exec", since = "1.15.0")]
     #[rustc_deprecated(since = "1.37.0", reason = "should be unsafe, use `pre_exec` instead")]
     fn before_exec<F>(&mut self, f: F) -> &mut process::Command
     where
         F: FnMut() -> io::Result<()> + Send + Sync + 'static,
     {
         unsafe { self.pre_exec(f) }
     }

     /// Performs all the required setup by this `Command`, followed by calling
     /// the `execvp` syscall.
     ///
     /// On success this function will not return, and otherwise it will return
     /// an error indicating why the exec (or another part of the setup of the
     /// `Command`) failed.
     ///
     /// `exec` not returning has the same implications as calling
     /// [`process::exit`] – no destructors on the current stack or any other
     /// thread’s stack will be run. Therefore, it is recommended to only call
     /// `exec` at a point where it is fine to not run any destructors. Note,
     /// that the `execvp` syscall independently guarantees that all memory is
     /// freed and all file descriptors with the `CLOEXEC` option (set by default
     /// on all file descriptors opened by the standard library) are closed.
     ///
     /// This function, unlike `spawn`, will **not** `fork` the process to create
     /// a new child. Like spawn, however, the default behavior for the stdio
     /// descriptors will be to inherited from the current process.
     ///
     /// # Notes
     ///
     /// The process may be in a "broken state" if this function returns in
     /// error. For example the working directory, environment variables, signal
     /// handling settings, various user/group information, or aspects of stdio
     /// file descriptors may have changed. If a "transactional spawn" is
     /// required to gracefully handle errors it is recommended to use the
     /// cross-platform `spawn` instead.
     #[stable(feature = "process_exec2", since = "1.9.0")]
     fn exec(&mut self) -> io::Error;

     /// Set executable argument
     ///
     /// Set the first process argument, `argv[0]`, to something other than the
     /// default executable path.
     #[stable(feature = "process_set_argv0", since = "1.45.0")]
     fn arg0<S>(&mut self, arg: S) -> &mut process::Command
     where
         S: AsRef<OsStr>;
 }

 #[stable(feature = "rust1", since = "1.0.0")]
 impl CommandExt for process::Command {
     fn uid(
         &mut self,
         #[cfg(not(target_os = "vxworks"))] id: u32,
         #[cfg(target_os = "vxworks")] id: u16,
     ) -> &mut process::Command {
         self.as_inner_mut().uid(id);
         self
     }

     fn gid(
         &mut self,
         #[cfg(not(target_os = "vxworks"))] id: u32,
         #[cfg(target_os = "vxworks")] id: u16,
     ) -> &mut process::Command {
         self.as_inner_mut().gid(id);
         self
     }

     fn groups(
         &mut self,
         #[cfg(not(target_os = "vxworks"))] groups: &[u32],
         #[cfg(target_os = "vxworks")] groups: &[u16],
     ) -> &mut process::Command {
         self.as_inner_mut().groups(groups);
         self
     }

     unsafe fn pre_exec<F>(&mut self, f: F) -> &mut process::Command
     where
         F: FnMut() -> io::Result<()> + Send + Sync + 'static,
     {
         self.as_inner_mut().pre_exec(Box::new(f));
         self
     }

     fn exec(&mut self) -> io::Error {
         // NOTE: This may *not* be safe to call after `libc::fork`, because it
         // may allocate. That may be worth fixing at some point in the future.
         self.as_inner_mut().exec(sys::process::Stdio::Inherit)
     }

     fn arg0<S>(&mut self, arg: S) -> &mut process::Command
     where
         S: AsRef<OsStr>,
     {
         self.as_inner_mut().set_arg_0(arg.as_ref());
         self
     }
 }

 /// Unix-specific extensions to [`process::ExitStatus`] and
 /// [`ExitStatusError`](process::ExitStatusError).
 ///
 /// On Unix, `ExitStatus` **does not necessarily represent an exit status**, as
 /// passed to the `exit` system call or returned by
 /// [`ExitStatus::code()`](crate::process::ExitStatus::code).  It represents **any wait status**
 /// as returned by one of the `wait` family of system
 /// calls.
 ///
 /// A Unix wait status (a Rust `ExitStatus`) can represent a Unix exit status, but can also
 /// represent other kinds of process event.
 ///
 /// This trait is sealed: it cannot be implemented outside the standard library.
 /// This is so that future additional methods are not breaking changes.
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait ExitStatusExt: Sealed {
     /// Creates a new `ExitStatus` or `ExitStatusError` from the raw underlying integer status
     /// value from `wait`
     ///
     /// The value should be a **wait status, not an exit status**.
     ///
     /// # Panics
     ///
     /// Panics on an attempt to make an `ExitStatusError` from a wait status of `0`.
     ///
     /// Making an `ExitStatus` always succeeds and never panics.
     #[stable(feature = "exit_status_from", since = "1.12.0")]
     fn from_raw(raw: i32) -> Self;

     /// If the process was terminated by a signal, returns that signal.
     ///
     /// In other words, if `WIFSIGNALED`, this returns `WTERMSIG`.
     #[stable(feature = "rust1", since = "1.0.0")]
     fn signal(&self) -> Option<i32>;

     /// If the process was terminated by a signal, says whether it dumped core.
     #[unstable(feature = "unix_process_wait_more", issue = "80695")]
     fn core_dumped(&self) -> bool;

     /// If the process was stopped by a signal, returns that signal.
     ///
     /// In other words, if `WIFSTOPPED`, this returns `WSTOPSIG`.  This is only possible if the status came from
     /// a `wait` system call which was passed `WUNTRACED`, and was then converted into an `ExitStatus`.
     #[unstable(feature = "unix_process_wait_more", issue = "80695")]
     fn stopped_signal(&self) -> Option<i32>;

     /// Whether the process was continued from a stopped status.
     ///
     /// Ie, `WIFCONTINUED`.  This is only possible if the status came from a `wait` system call
     /// which was passed `WCONTINUED`, and was then converted into an `ExitStatus`.
     #[unstable(feature = "unix_process_wait_more", issue = "80695")]
     fn continued(&self) -> bool;

     /// Returns the underlying raw `wait` status.
     ///
     /// The returned integer is a **wait status, not an exit status**.
     #[unstable(feature = "unix_process_wait_more", issue = "80695")]
     fn into_raw(self) -> i32;
 }

 #[stable(feature = "rust1", since = "1.0.0")]
 impl ExitStatusExt for process::ExitStatus {
     fn from_raw(raw: i32) -> Self {
         process::ExitStatus::from_inner(From::from(raw))
     }

     fn signal(&self) -> Option<i32> {
         self.as_inner().signal()
     }

     fn core_dumped(&self) -> bool {
         self.as_inner().core_dumped()
     }

     fn stopped_signal(&self) -> Option<i32> {
         self.as_inner().stopped_signal()
     }

     fn continued(&self) -> bool {
         self.as_inner().continued()
     }

     fn into_raw(self) -> i32 {
         self.as_inner().into_raw().into()
     }
 }

 #[unstable(feature = "exit_status_error", issue = "84908")]
 impl ExitStatusExt for process::ExitStatusError {
     fn from_raw(raw: i32) -> Self {
         process::ExitStatus::from_raw(raw)
             .exit_ok()
             .expect_err("<ExitStatusError as ExitStatusExt>::from_raw(0) but zero is not an error")
     }

     fn signal(&self) -> Option<i32> {
         self.into_status().signal()
     }

     fn core_dumped(&self) -> bool {
         self.into_status().core_dumped()
     }

     fn stopped_signal(&self) -> Option<i32> {
         self.into_status().stopped_signal()
     }

     fn continued(&self) -> bool {
         self.into_status().continued()
     }

     fn into_raw(self) -> i32 {
         self.into_status().into_raw()
     }
 }

 #[stable(feature = "process_extensions", since = "1.2.0")]
 impl FromRawFd for process::Stdio {
     #[inline]
     unsafe fn from_raw_fd(fd: RawFd) -> process::Stdio {
         let fd = sys::fd::FileDesc::from_raw_fd(fd);
         let io = sys::process::Stdio::Fd(fd);
         process::Stdio::from_inner(io)
     }
 }

 #[unstable(feature = "io_safety", issue = "87074")]
 impl From<OwnedFd> for process::Stdio {
     #[inline]
     fn from(fd: OwnedFd) -> process::Stdio {
         let fd = sys::fd::FileDesc::from_inner(fd);
         let io = sys::process::Stdio::Fd(fd);
         process::Stdio::from_inner(io)
     }
 }

 #[stable(feature = "process_extensions", since = "1.2.0")]
 impl AsRawFd for process::ChildStdin {
     #[inline]
     fn as_raw_fd(&self) -> RawFd {
         self.as_inner().as_raw_fd()
     }
 }

 #[stable(feature = "process_extensions", since = "1.2.0")]
 impl AsRawFd for process::ChildStdout {
     #[inline]
     fn as_raw_fd(&self) -> RawFd {
         self.as_inner().as_raw_fd()
     }
 }

 #[stable(feature = "process_extensions", since = "1.2.0")]
 impl AsRawFd for process::ChildStderr {
     #[inline]
     fn as_raw_fd(&self) -> RawFd {
         self.as_inner().as_raw_fd()
     }
 }

 #[stable(feature = "into_raw_os", since = "1.4.0")]
 impl IntoRawFd for process::ChildStdin {
     #[inline]
     fn into_raw_fd(self) -> RawFd {
         self.into_inner().into_inner().into_raw_fd()
     }
 }

 #[stable(feature = "into_raw_os", since = "1.4.0")]
 impl IntoRawFd for process::ChildStdout {
     #[inline]
     fn into_raw_fd(self) -> RawFd {
         self.into_inner().into_inner().into_raw_fd()
     }
 }

 #[stable(feature = "into_raw_os", since = "1.4.0")]
 impl IntoRawFd for process::ChildStderr {
     #[inline]
     fn into_raw_fd(self) -> RawFd {
         self.into_inner().into_inner().into_raw_fd()
     }
 }

 #[unstable(feature = "io_safety", issue = "87074")]
 impl AsFd for crate::process::ChildStdin {
     #[inline]
     fn as_fd(&self) -> BorrowedFd<'_> {
         self.as_inner().as_fd()
     }
 }

 #[unstable(feature = "io_safety", issue = "87074")]
 impl From<crate::process::ChildStdin> for OwnedFd {
     #[inline]
     fn from(child_stdin: crate::process::ChildStdin) -> OwnedFd {
         child_stdin.into_inner().into_inner().into_inner()
     }
 }

 #[unstable(feature = "io_safety", issue = "87074")]
 impl AsFd for crate::process::ChildStdout {
     #[inline]
     fn as_fd(&self) -> BorrowedFd<'_> {
         self.as_inner().as_fd()
     }
 }

 #[unstable(feature = "io_safety", issue = "87074")]
 impl From<crate::process::ChildStdout> for OwnedFd {
     #[inline]
     fn from(child_stdout: crate::process::ChildStdout) -> OwnedFd {
         child_stdout.into_inner().into_inner().into_inner()
     }
 }

 #[unstable(feature = "io_safety", issue = "87074")]
 impl AsFd for crate::process::ChildStderr {
     #[inline]
     fn as_fd(&self) -> BorrowedFd<'_> {
         self.as_inner().as_fd()
     }
 }

 #[unstable(feature = "io_safety", issue = "87074")]
 impl From<crate::process::ChildStderr> for OwnedFd {
     #[inline]
     fn from(child_stderr: crate::process::ChildStderr) -> OwnedFd {
         child_stderr.into_inner().into_inner().into_inner()
     }
 }

 /// Returns the OS-assigned process identifier associated with this process's parent.
 #[stable(feature = "unix_ppid", since = "1.27.0")]
 pub fn parent_id() -> u32 {
     crate::sys::os::getppid()
 }
	//! Unix-specific extensions to primitives in the `std::process` module.

	#![stable(feature = "rust1", since = "1.0.0")]

	use crate::ffi::OsStr;
	use crate::io;
	use crate::os::unix::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, OwnedFd, RawFd};
	use crate::process;
	use crate::sealed::Sealed;
	use crate::sys;
	use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner};

	/// Unix-specific extensions to the [`process::Command`] builder.
	///
	/// This trait is sealed: it cannot be implemented outside the standard library.
	/// This is so that future additional methods are not breaking changes.
	#[stable(feature = "rust1", since = "1.0.0")]
	pub trait CommandExt: Sealed {
	/// Sets the child process's user ID. This translates to a
	/// `setuid` call in the child process. Failure in the `setuid`
	/// call will cause the spawn to fail.
	#[stable(feature = "rust1", since = "1.0.0")]
	fn uid(
	&mut self,
	#[cfg(not(target_os = "vxworks"))] id: u32,
	#[cfg(target_os = "vxworks")] id: u16,
	) -> &mut process::Command;

	/// Similar to `uid`, but sets the group ID of the child process. This has
	/// the same semantics as the `uid` field.
	#[stable(feature = "rust1", since = "1.0.0")]
	fn gid(
	&mut self,
	#[cfg(not(target_os = "vxworks"))] id: u32,
	#[cfg(target_os = "vxworks")] id: u16,
	) -> &mut process::Command;

	/// Sets the supplementary group IDs for the calling process. Translates to
	/// a `setgroups` call in the child process.
	#[unstable(feature = "setgroups", issue = "38527", reason = "")]
	fn groups(
	&mut self,
	#[cfg(not(target_os = "vxworks"))] groups: &[u32],
	#[cfg(target_os = "vxworks")] groups: &[u16],
	) -> &mut process::Command;

	/// Schedules a closure to be run just before the `exec` function is
	/// invoked.
	///
	/// The closure is allowed to return an I/O error whose OS error code will
	/// be communicated back to the parent and returned as an error from when
	/// the spawn was requested.
	///
	/// Multiple closures can be registered and they will be called in order of
	/// their registration. If a closure returns `Err` then no further closures
	/// will be called and the spawn operation will immediately return with a
	/// failure.
	///
	/// # Notes and Safety
	///
	/// This closure will be run in the context of the child process after a
	/// `fork`. This primarily means that any modifications made to memory on
	/// behalf of this closure will not be visible to the parent process.
	/// This is often a very constrained environment where normal operations
	/// like `malloc`, accessing environment variables through [`std::env`]
	/// or acquiring a mutex are not guaranteed to work (due to
	/// other threads perhaps still running when the `fork` was run).
	///
	/// For further details refer to the [POSIX fork() specification]
	/// and the equivalent documentation for any targeted
	/// platform, especially the requirements around async-signal-safety.
	///
	/// This also means that all resources such as file descriptors and
	/// memory-mapped regions got duplicated. It is your responsibility to make
	/// sure that the closure does not violate library invariants by making
	/// invalid use of these duplicates.
	///
	/// Panicking in the closure is safe only if all the format arguments for the
	/// panic message can be safely formatted; this is because although
	/// `Command` calls [`std::panic::always_abort`](crate::panic::always_abort)
	/// before calling the pre_exec hook, panic will still try to format the
	/// panic message.
	///
	/// When this closure is run, aspects such as the stdio file descriptors and
	/// working directory have successfully been changed, so output to these
	/// locations might not appear where intended.
	///
	/// [POSIX fork() specification]:
	/// https://pubs.opengroup.org/onlinepubs/9699919799/functions/fork.html
	/// [`std::env`]: mod@crate::env
	#[stable(feature = "process_pre_exec", since = "1.34.0")]
	unsafe fn pre_exec<F>(&mut self, f: F) -> &mut process::Command
	where
	F: FnMut() -> io::Result<()> + Send + Sync + 'static;

	/// Schedules a closure to be run just before the `exec` function is
	/// invoked.
	///
	/// This method is stable and usable, but it should be unsafe. To fix
	/// that, it got deprecated in favor of the unsafe [`pre_exec`].
	///
	/// [`pre_exec`]: CommandExt::pre_exec
	#[stable(feature = "process_exec", since = "1.15.0")]
	#[rustc_deprecated(since = "1.37.0", reason = "should be unsafe, use `pre_exec` instead")]
	fn before_exec<F>(&mut self, f: F) -> &mut process::Command
	where
	F: FnMut() -> io::Result<()> + Send + Sync + 'static,
	{
	unsafe { self.pre_exec(f) }
	}

	/// Performs all the required setup by this `Command`, followed by calling
	/// the `execvp` syscall.
	///
	/// On success this function will not return, and otherwise it will return
	/// an error indicating why the exec (or another part of the setup of the
	/// `Command`) failed.
	///
	/// `exec` not returning has the same implications as calling
	/// [`process::exit`] – no destructors on the current stack or any other
	/// thread’s stack will be run. Therefore, it is recommended to only call
	/// `exec` at a point where it is fine to not run any destructors. Note,
	/// that the `execvp` syscall independently guarantees that all memory is
	/// freed and all file descriptors with the `CLOEXEC` option (set by default
	/// on all file descriptors opened by the standard library) are closed.
	///
	/// This function, unlike `spawn`, will not `fork` the process to create
	/// a new child. Like spawn, however, the default behavior for the stdio
	/// descriptors will be to inherited from the current process.
	///
	/// # Notes
	///
	/// The process may be in a "broken state" if this function returns in
	/// error. For example the working directory, environment variables, signal
	/// handling settings, various user/group information, or aspects of stdio
	/// file descriptors may have changed. If a "transactional spawn" is
	/// required to gracefully handle errors it is recommended to use the
	/// cross-platform `spawn` instead.
	#[stable(feature = "process_exec2", since = "1.9.0")]
	fn exec(&mut self) -> io::Error;

	/// Set executable argument
	///
	/// Set the first process argument, `argv[0]`, to something other than the
	/// default executable path.
	#[stable(feature = "process_set_argv0", since = "1.45.0")]
	fn arg0<S>(&mut self, arg: S) -> &mut process::Command
	where
	S: AsRef<OsStr>;
	}

	#[stable(feature = "rust1", since = "1.0.0")]
	impl CommandExt for process::Command {
	fn uid(
	&mut self,
	#[cfg(not(target_os = "vxworks"))] id: u32,
	#[cfg(target_os = "vxworks")] id: u16,
	) -> &mut process::Command {
	self.as_inner_mut().uid(id);
	self
	}

	fn gid(
	&mut self,
	#[cfg(not(target_os = "vxworks"))] id: u32,
	#[cfg(target_os = "vxworks")] id: u16,
	) -> &mut process::Command {
	self.as_inner_mut().gid(id);
	self
	}

	fn groups(
	&mut self,
	#[cfg(not(target_os = "vxworks"))] groups: &[u32],
	#[cfg(target_os = "vxworks")] groups: &[u16],
	) -> &mut process::Command {
	self.as_inner_mut().groups(groups);
	self
	}

	unsafe fn pre_exec<F>(&mut self, f: F) -> &mut process::Command
	where
	F: FnMut() -> io::Result<()> + Send + Sync + 'static,
	{
	self.as_inner_mut().pre_exec(Box::new(f));
	self
	}

	fn exec(&mut self) -> io::Error {
	// NOTE: This may not be safe to call after `libc::fork`, because it
	// may allocate. That may be worth fixing at some point in the future.
	self.as_inner_mut().exec(sys::process::Stdio::Inherit)
	}

	fn arg0<S>(&mut self, arg: S) -> &mut process::Command
	where
	S: AsRef<OsStr>,
	{
	self.as_inner_mut().set_arg_0(arg.as_ref());
	self
	}
	}

	/// Unix-specific extensions to [`process::ExitStatus`] and
	/// [`ExitStatusError`](process::ExitStatusError).
	///
	/// On Unix, `ExitStatus` does not necessarily represent an exit status, as
	/// passed to the `exit` system call or returned by
	/// [`ExitStatus::code()`](crate::process::ExitStatus::code). It represents any wait status
	/// as returned by one of the `wait` family of system
	/// calls.
	///
	/// A Unix wait status (a Rust `ExitStatus`) can represent a Unix exit status, but can also
	/// represent other kinds of process event.
	///
	/// This trait is sealed: it cannot be implemented outside the standard library.
	/// This is so that future additional methods are not breaking changes.
	#[stable(feature = "rust1", since = "1.0.0")]
	pub trait ExitStatusExt: Sealed {
	/// Creates a new `ExitStatus` or `ExitStatusError` from the raw underlying integer status
	/// value from `wait`
	///
	/// The value should be a wait status, not an exit status.
	///
	/// # Panics
	///
	/// Panics on an attempt to make an `ExitStatusError` from a wait status of `0`.
	///
	/// Making an `ExitStatus` always succeeds and never panics.
	#[stable(feature = "exit_status_from", since = "1.12.0")]
	fn from_raw(raw: i32) -> Self;

	/// If the process was terminated by a signal, returns that signal.
	///
	/// In other words, if `WIFSIGNALED`, this returns `WTERMSIG`.
	#[stable(feature = "rust1", since = "1.0.0")]
	fn signal(&self) -> Option<i32>;

	/// If the process was terminated by a signal, says whether it dumped core.
	#[unstable(feature = "unix_process_wait_more", issue = "80695")]
	fn core_dumped(&self) -> bool;

	/// If the process was stopped by a signal, returns that signal.
	///
	/// In other words, if `WIFSTOPPED`, this returns `WSTOPSIG`. This is only possible if the status came from
	/// a `wait` system call which was passed `WUNTRACED`, and was then converted into an `ExitStatus`.
	#[unstable(feature = "unix_process_wait_more", issue = "80695")]
	fn stopped_signal(&self) -> Option<i32>;

	/// Whether the process was continued from a stopped status.
	///
	/// Ie, `WIFCONTINUED`. This is only possible if the status came from a `wait` system call
	/// which was passed `WCONTINUED`, and was then converted into an `ExitStatus`.
	#[unstable(feature = "unix_process_wait_more", issue = "80695")]
	fn continued(&self) -> bool;

	/// Returns the underlying raw `wait` status.
	///
	/// The returned integer is a wait status, not an exit status.
	#[unstable(feature = "unix_process_wait_more", issue = "80695")]
	fn into_raw(self) -> i32;
	}

	#[stable(feature = "rust1", since = "1.0.0")]
	impl ExitStatusExt for process::ExitStatus {
	fn from_raw(raw: i32) -> Self {
	process::ExitStatus::from_inner(From::from(raw))
	}

	fn signal(&self) -> Option<i32> {
	self.as_inner().signal()
	}

	fn core_dumped(&self) -> bool {
	self.as_inner().core_dumped()
	}

	fn stopped_signal(&self) -> Option<i32> {
	self.as_inner().stopped_signal()
	}

	fn continued(&self) -> bool {
	self.as_inner().continued()
	}

	fn into_raw(self) -> i32 {
	self.as_inner().into_raw().into()
	}
	}

	#[unstable(feature = "exit_status_error", issue = "84908")]
	impl ExitStatusExt for process::ExitStatusError {
	fn from_raw(raw: i32) -> Self {
	process::ExitStatus::from_raw(raw)
	.exit_ok()
	.expect_err("<ExitStatusError as ExitStatusExt>::from_raw(0) but zero is not an error")
	}

	fn signal(&self) -> Option<i32> {
	self.into_status().signal()
	}

	fn core_dumped(&self) -> bool {
	self.into_status().core_dumped()
	}

	fn stopped_signal(&self) -> Option<i32> {
	self.into_status().stopped_signal()
	}

	fn continued(&self) -> bool {
	self.into_status().continued()
	}

	fn into_raw(self) -> i32 {
	self.into_status().into_raw()
	}
	}

	#[stable(feature = "process_extensions", since = "1.2.0")]
	impl FromRawFd for process::Stdio {
	#[inline]
	unsafe fn from_raw_fd(fd: RawFd) -> process::Stdio {
	let fd = sys::fd::FileDesc::from_raw_fd(fd);
	let io = sys::process::Stdio::Fd(fd);
	process::Stdio::from_inner(io)
	}
	}

	#[unstable(feature = "io_safety", issue = "87074")]
	impl From<OwnedFd> for process::Stdio {
	#[inline]
	fn from(fd: OwnedFd) -> process::Stdio {
	let fd = sys::fd::FileDesc::from_inner(fd);
	let io = sys::process::Stdio::Fd(fd);
	process::Stdio::from_inner(io)
	}
	}

	#[stable(feature = "process_extensions", since = "1.2.0")]
	impl AsRawFd for process::ChildStdin {
	#[inline]
	fn as_raw_fd(&self) -> RawFd {
	self.as_inner().as_raw_fd()
	}
	}

	#[stable(feature = "process_extensions", since = "1.2.0")]
	impl AsRawFd for process::ChildStdout {
	#[inline]
	fn as_raw_fd(&self) -> RawFd {
	self.as_inner().as_raw_fd()
	}
	}

	#[stable(feature = "process_extensions", since = "1.2.0")]
	impl AsRawFd for process::ChildStderr {
	#[inline]
	fn as_raw_fd(&self) -> RawFd {
	self.as_inner().as_raw_fd()
	}
	}

	#[stable(feature = "into_raw_os", since = "1.4.0")]
	impl IntoRawFd for process::ChildStdin {
	#[inline]
	fn into_raw_fd(self) -> RawFd {
	self.into_inner().into_inner().into_raw_fd()
	}
	}

	#[stable(feature = "into_raw_os", since = "1.4.0")]
	impl IntoRawFd for process::ChildStdout {
	#[inline]
	fn into_raw_fd(self) -> RawFd {
	self.into_inner().into_inner().into_raw_fd()
	}
	}

	#[stable(feature = "into_raw_os", since = "1.4.0")]
	impl IntoRawFd for process::ChildStderr {
	#[inline]
	fn into_raw_fd(self) -> RawFd {
	self.into_inner().into_inner().into_raw_fd()
	}
	}

	#[unstable(feature = "io_safety", issue = "87074")]
	impl AsFd for crate::process::ChildStdin {
	#[inline]
	fn as_fd(&self) -> BorrowedFd<'_> {
	self.as_inner().as_fd()
	}
	}

	#[unstable(feature = "io_safety", issue = "87074")]
	impl From<crate::process::ChildStdin> for OwnedFd {
	#[inline]
	fn from(child_stdin: crate::process::ChildStdin) -> OwnedFd {
	child_stdin.into_inner().into_inner().into_inner()
	}
	}

	#[unstable(feature = "io_safety", issue = "87074")]
	impl AsFd for crate::process::ChildStdout {
	#[inline]
	fn as_fd(&self) -> BorrowedFd<'_> {
	self.as_inner().as_fd()
	}
	}

	#[unstable(feature = "io_safety", issue = "87074")]
	impl From<crate::process::ChildStdout> for OwnedFd {
	#[inline]
	fn from(child_stdout: crate::process::ChildStdout) -> OwnedFd {
	child_stdout.into_inner().into_inner().into_inner()
	}
	}

	#[unstable(feature = "io_safety", issue = "87074")]
	impl AsFd for crate::process::ChildStderr {
	#[inline]
	fn as_fd(&self) -> BorrowedFd<'_> {
	self.as_inner().as_fd()
	}
	}

	#[unstable(feature = "io_safety", issue = "87074")]
	impl From<crate::process::ChildStderr> for OwnedFd {
	#[inline]
	fn from(child_stderr: crate::process::ChildStderr) -> OwnedFd {
	child_stderr.into_inner().into_inner().into_inner()
	}
	}

	/// Returns the OS-assigned process identifier associated with this process's parent.
	#[stable(feature = "unix_ppid", since = "1.27.0")]
	pub fn parent_id() -> u32 {
	crate::sys::os::getppid()
	}