mv std libs to library/

5 files changed, 1543 insertions, 0 deletions

diff --git a/library/std/src/sys/unix/process/mod.rs b/library/std/src/sys/unix/process/mod.rs
new file mode 100644
index 00000000000..553e980f08e
--- /dev/null
+++ b/library/std/src/sys/unix/process/mod.rs
@@ -0,0 +1,13 @@
+pub use self::process_common::{Command, ExitCode, Stdio, StdioPipes};
+pub use self::process_inner::{ExitStatus, Process};
+pub use crate::ffi::OsString as EnvKey;
+
+mod process_common;
+#[cfg(not(target_os = "fuchsia"))]
+#[path = "process_unix.rs"]
+mod process_inner;
+#[cfg(target_os = "fuchsia")]
+#[path = "process_fuchsia.rs"]
+mod process_inner;
+#[cfg(target_os = "fuchsia")]
+mod zircon;
diff --git a/library/std/src/sys/unix/process/process_common.rs b/library/std/src/sys/unix/process/process_common.rs
new file mode 100644
index 00000000000..6e33cdd3c48
--- /dev/null
+++ b/library/std/src/sys/unix/process/process_common.rs
@@ -0,0 +1,469 @@
+use crate::os::unix::prelude::*;
+
+use crate::collections::BTreeMap;
+use crate::ffi::{CStr, CString, OsStr, OsString};
+use crate::fmt;
+use crate::io;
+use crate::ptr;
+use crate::sys::fd::FileDesc;
+use crate::sys::fs::File;
+use crate::sys::pipe::{self, AnonPipe};
+use crate::sys_common::process::CommandEnv;
+
+#[cfg(not(target_os = "fuchsia"))]
+use crate::sys::fs::OpenOptions;
+
+use libc::{c_char, c_int, gid_t, uid_t, EXIT_FAILURE, EXIT_SUCCESS};
+
+cfg_if::cfg_if! {
+    if #[cfg(target_os = "fuchsia")] {
+        // fuchsia doesn't have /dev/null
+    } else if #[cfg(target_os = "redox")] {
+        const DEV_NULL: &str = "null:\0";
+    } else {
+        const DEV_NULL: &str = "/dev/null\0";
+    }
+}
+
+// Android with api less than 21 define sig* functions inline, so it is not
+// available for dynamic link. Implementing sigemptyset and sigaddset allow us
+// to support older Android version (independent of libc version).
+// The following implementations are based on https://git.io/vSkNf
+cfg_if::cfg_if! {
+    if #[cfg(target_os = "android")] {
+        pub unsafe fn sigemptyset(set: *mut libc::sigset_t) -> libc::c_int {
+            set.write_bytes(0u8, 1);
+            return 0;
+        }
+        #[allow(dead_code)]
+        pub unsafe fn sigaddset(set: *mut libc::sigset_t, signum: libc::c_int) -> libc::c_int {
+            use crate::{slice, mem};
+
+            let raw = slice::from_raw_parts_mut(set as *mut u8, mem::size_of::<libc::sigset_t>());
+            let bit = (signum - 1) as usize;
+            raw[bit / 8] |= 1 << (bit % 8);
+            return 0;
+        }
+    } else {
+        pub use libc::{sigemptyset, sigaddset};
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Command
+////////////////////////////////////////////////////////////////////////////////
+
+pub struct Command {
+    // Currently we try hard to ensure that the call to `.exec()` doesn't
+    // actually allocate any memory. While many platforms try to ensure that
+    // memory allocation works after a fork in a multithreaded process, it's
+    // been observed to be buggy and somewhat unreliable, so we do our best to
+    // just not do it at all!
+    //
+    // Along those lines, the `argv` and `envp` raw pointers here are exactly
+    // what's gonna get passed to `execvp`. The `argv` array starts with the
+    // `program` and ends with a NULL, and the `envp` pointer, if present, is
+    // also null-terminated.
+    //
+    // Right now we don't support removing arguments, so there's no much fancy
+    // support there, but we support adding and removing environment variables,
+    // so a side table is used to track where in the `envp` array each key is
+    // located. Whenever we add a key we update it in place if it's already
+    // present, and whenever we remove a key we update the locations of all
+    // other keys.
+    program: CString,
+    args: Vec<CString>,
+    argv: Argv,
+    env: CommandEnv,
+
+    cwd: Option<CString>,
+    uid: Option<uid_t>,
+    gid: Option<gid_t>,
+    saw_nul: bool,
+    closures: Vec<Box<dyn FnMut() -> io::Result<()> + Send + Sync>>,
+    stdin: Option<Stdio>,
+    stdout: Option<Stdio>,
+    stderr: Option<Stdio>,
+}
+
+// Create a new type for argv, so that we can make it `Send` and `Sync`
+struct Argv(Vec<*const c_char>);
+
+// It is safe to make `Argv` `Send` and `Sync`, because it contains
+// pointers to memory owned by `Command.args`
+unsafe impl Send for Argv {}
+unsafe impl Sync for Argv {}
+
+// passed back to std::process with the pipes connected to the child, if any
+// were requested
+pub struct StdioPipes {
+    pub stdin: Option<AnonPipe>,
+    pub stdout: Option<AnonPipe>,
+    pub stderr: Option<AnonPipe>,
+}
+
+// passed to do_exec() with configuration of what the child stdio should look
+// like
+pub struct ChildPipes {
+    pub stdin: ChildStdio,
+    pub stdout: ChildStdio,
+    pub stderr: ChildStdio,
+}
+
+pub enum ChildStdio {
+    Inherit,
+    Explicit(c_int),
+    Owned(FileDesc),
+
+    // On Fuchsia, null stdio is the default, so we simply don't specify
+    // any actions at the time of spawning.
+    #[cfg(target_os = "fuchsia")]
+    Null,
+}
+
+pub enum Stdio {
+    Inherit,
+    Null,
+    MakePipe,
+    Fd(FileDesc),
+}
+
+impl Command {
+    pub fn new(program: &OsStr) -> Command {
+        let mut saw_nul = false;
+        let program = os2c(program, &mut saw_nul);
+        Command {
+            argv: Argv(vec![program.as_ptr(), ptr::null()]),
+            args: vec![program.clone()],
+            program,
+            env: Default::default(),
+            cwd: None,
+            uid: None,
+            gid: None,
+            saw_nul,
+            closures: Vec::new(),
+            stdin: None,
+            stdout: None,
+            stderr: None,
+        }
+    }
+
+    pub fn set_arg_0(&mut self, arg: &OsStr) {
+        // Set a new arg0
+        let arg = os2c(arg, &mut self.saw_nul);
+        debug_assert!(self.argv.0.len() > 1);
+        self.argv.0[0] = arg.as_ptr();
+        self.args[0] = arg;
+    }
+
+    pub fn arg(&mut self, arg: &OsStr) {
+        // Overwrite the trailing NULL pointer in `argv` and then add a new null
+        // pointer.
+        let arg = os2c(arg, &mut self.saw_nul);
+        self.argv.0[self.args.len()] = arg.as_ptr();
+        self.argv.0.push(ptr::null());
+
+        // Also make sure we keep track of the owned value to schedule a
+        // destructor for this memory.
+        self.args.push(arg);
+    }
+
+    pub fn cwd(&mut self, dir: &OsStr) {
+        self.cwd = Some(os2c(dir, &mut self.saw_nul));
+    }
+    pub fn uid(&mut self, id: uid_t) {
+        self.uid = Some(id);
+    }
+    pub fn gid(&mut self, id: gid_t) {
+        self.gid = Some(id);
+    }
+
+    pub fn saw_nul(&self) -> bool {
+        self.saw_nul
+    }
+    pub fn get_argv(&self) -> &Vec<*const c_char> {
+        &self.argv.0
+    }
+
+    pub fn get_program(&self) -> &CStr {
+        &*self.program
+    }
+
+    #[allow(dead_code)]
+    pub fn get_cwd(&self) -> &Option<CString> {
+        &self.cwd
+    }
+    #[allow(dead_code)]
+    pub fn get_uid(&self) -> Option<uid_t> {
+        self.uid
+    }
+    #[allow(dead_code)]
+    pub fn get_gid(&self) -> Option<gid_t> {
+        self.gid
+    }
+
+    pub fn get_closures(&mut self) -> &mut Vec<Box<dyn FnMut() -> io::Result<()> + Send + Sync>> {
+        &mut self.closures
+    }
+
+    pub unsafe fn pre_exec(&mut self, f: Box<dyn FnMut() -> io::Result<()> + Send + Sync>) {
+        self.closures.push(f);
+    }
+
+    pub fn stdin(&mut self, stdin: Stdio) {
+        self.stdin = Some(stdin);
+    }
+
+    pub fn stdout(&mut self, stdout: Stdio) {
+        self.stdout = Some(stdout);
+    }
+
+    pub fn stderr(&mut self, stderr: Stdio) {
+        self.stderr = Some(stderr);
+    }
+
+    pub fn env_mut(&mut self) -> &mut CommandEnv {
+        &mut self.env
+    }
+
+    pub fn capture_env(&mut self) -> Option<CStringArray> {
+        let maybe_env = self.env.capture_if_changed();
+        maybe_env.map(|env| construct_envp(env, &mut self.saw_nul))
+    }
+    #[allow(dead_code)]
+    pub fn env_saw_path(&self) -> bool {
+        self.env.have_changed_path()
+    }
+
+    pub fn setup_io(
+        &self,
+        default: Stdio,
+        needs_stdin: bool,
+    ) -> io::Result<(StdioPipes, ChildPipes)> {
+        let null = Stdio::Null;
+        let default_stdin = if needs_stdin { &default } else { &null };
+        let stdin = self.stdin.as_ref().unwrap_or(default_stdin);
+        let stdout = self.stdout.as_ref().unwrap_or(&default);
+        let stderr = self.stderr.as_ref().unwrap_or(&default);
+        let (their_stdin, our_stdin) = stdin.to_child_stdio(true)?;
+        let (their_stdout, our_stdout) = stdout.to_child_stdio(false)?;
+        let (their_stderr, our_stderr) = stderr.to_child_stdio(false)?;
+        let ours = StdioPipes { stdin: our_stdin, stdout: our_stdout, stderr: our_stderr };
+        let theirs = ChildPipes { stdin: their_stdin, stdout: their_stdout, stderr: their_stderr };
+        Ok((ours, theirs))
+    }
+}
+
+fn os2c(s: &OsStr, saw_nul: &mut bool) -> CString {
+    CString::new(s.as_bytes()).unwrap_or_else(|_e| {
+        *saw_nul = true;
+        CString::new("<string-with-nul>").unwrap()
+    })
+}
+
+// Helper type to manage ownership of the strings within a C-style array.
+pub struct CStringArray {
+    items: Vec<CString>,
+    ptrs: Vec<*const c_char>,
+}
+
+impl CStringArray {
+    pub fn with_capacity(capacity: usize) -> Self {
+        let mut result = CStringArray {
+            items: Vec::with_capacity(capacity),
+            ptrs: Vec::with_capacity(capacity + 1),
+        };
+        result.ptrs.push(ptr::null());
+        result
+    }
+    pub fn push(&mut self, item: CString) {
+        let l = self.ptrs.len();
+        self.ptrs[l - 1] = item.as_ptr();
+        self.ptrs.push(ptr::null());
+        self.items.push(item);
+    }
+    pub fn as_ptr(&self) -> *const *const c_char {
+        self.ptrs.as_ptr()
+    }
+}
+
+fn construct_envp(env: BTreeMap<OsString, OsString>, saw_nul: &mut bool) -> CStringArray {
+    let mut result = CStringArray::with_capacity(env.len());
+    for (mut k, v) in env {
+        // Reserve additional space for '=' and null terminator
+        k.reserve_exact(v.len() + 2);
+        k.push("=");
+        k.push(&v);
+
+        // Add the new entry into the array
+        if let Ok(item) = CString::new(k.into_vec()) {
+            result.push(item);
+        } else {
+            *saw_nul = true;
+        }
+    }
+
+    result
+}
+
+impl Stdio {
+    pub fn to_child_stdio(&self, readable: bool) -> io::Result<(ChildStdio, Option<AnonPipe>)> {
+        match *self {
+            Stdio::Inherit => Ok((ChildStdio::Inherit, None)),
+
+            // Make sure that the source descriptors are not an stdio
+            // descriptor, otherwise the order which we set the child's
+            // descriptors may blow away a descriptor which we are hoping to
+            // save. For example, suppose we want the child's stderr to be the
+            // parent's stdout, and the child's stdout to be the parent's
+            // stderr. No matter which we dup first, the second will get
+            // overwritten prematurely.
+            Stdio::Fd(ref fd) => {
+                if fd.raw() >= 0 && fd.raw() <= libc::STDERR_FILENO {
+                    Ok((ChildStdio::Owned(fd.duplicate()?), None))
+                } else {
+                    Ok((ChildStdio::Explicit(fd.raw()), None))
+                }
+            }
+
+            Stdio::MakePipe => {
+                let (reader, writer) = pipe::anon_pipe()?;
+                let (ours, theirs) = if readable { (writer, reader) } else { (reader, writer) };
+                Ok((ChildStdio::Owned(theirs.into_fd()), Some(ours)))
+            }
+
+            #[cfg(not(target_os = "fuchsia"))]
+            Stdio::Null => {
+                let mut opts = OpenOptions::new();
+                opts.read(readable);
+                opts.write(!readable);
+                let path = unsafe { CStr::from_ptr(DEV_NULL.as_ptr() as *const _) };
+                let fd = File::open_c(&path, &opts)?;
+                Ok((ChildStdio::Owned(fd.into_fd()), None))
+            }
+
+            #[cfg(target_os = "fuchsia")]
+            Stdio::Null => Ok((ChildStdio::Null, None)),
+        }
+    }
+}
+
+impl From<AnonPipe> for Stdio {
+    fn from(pipe: AnonPipe) -> Stdio {
+        Stdio::Fd(pipe.into_fd())
+    }
+}
+
+impl From<File> for Stdio {
+    fn from(file: File) -> Stdio {
+        Stdio::Fd(file.into_fd())
+    }
+}
+
+impl ChildStdio {
+    pub fn fd(&self) -> Option<c_int> {
+        match *self {
+            ChildStdio::Inherit => None,
+            ChildStdio::Explicit(fd) => Some(fd),
+            ChildStdio::Owned(ref fd) => Some(fd.raw()),
+
+            #[cfg(target_os = "fuchsia")]
+            ChildStdio::Null => None,
+        }
+    }
+}
+
+impl fmt::Debug for Command {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if self.program != self.args[0] {
+            write!(f, "[{:?}] ", self.program)?;
+        }
+        write!(f, "{:?}", self.args[0])?;
+
+        for arg in &self.args[1..] {
+            write!(f, " {:?}", arg)?;
+        }
+        Ok(())
+    }
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+pub struct ExitCode(u8);
+
+impl ExitCode {
+    pub const SUCCESS: ExitCode = ExitCode(EXIT_SUCCESS as _);
+    pub const FAILURE: ExitCode = ExitCode(EXIT_FAILURE as _);
+
+    #[inline]
+    pub fn as_i32(&self) -> i32 {
+        self.0 as i32
+    }
+}
+
+#[cfg(all(test, not(target_os = "emscripten")))]
+mod tests {
+    use super::*;
+
+    use crate::ffi::OsStr;
+    use crate::mem;
+    use crate::ptr;
+    use crate::sys::cvt;
+
+    macro_rules! t {
+        ($e:expr) => {
+            match $e {
+                Ok(t) => t,
+                Err(e) => panic!("received error for `{}`: {}", stringify!($e), e),
+            }
+        };
+    }
+
+    // See #14232 for more information, but it appears that signal delivery to a
+    // newly spawned process may just be raced in the macOS, so to prevent this
+    // test from being flaky we ignore it on macOS.
+    #[test]
+    #[cfg_attr(target_os = "macos", ignore)]
+    // When run under our current QEMU emulation test suite this test fails,
+    // although the reason isn't very clear as to why. For now this test is
+    // ignored there.
+    #[cfg_attr(target_arch = "arm", ignore)]
+    #[cfg_attr(target_arch = "aarch64", ignore)]
+    #[cfg_attr(target_arch = "riscv64", ignore)]
+    fn test_process_mask() {
+        unsafe {
+            // Test to make sure that a signal mask does not get inherited.
+            let mut cmd = Command::new(OsStr::new("cat"));
+
+            let mut set = mem::MaybeUninit::<libc::sigset_t>::uninit();
+            let mut old_set = mem::MaybeUninit::<libc::sigset_t>::uninit();
+            t!(cvt(sigemptyset(set.as_mut_ptr())));
+            t!(cvt(sigaddset(set.as_mut_ptr(), libc::SIGINT)));
+            t!(cvt(libc::pthread_sigmask(libc::SIG_SETMASK, set.as_ptr(), old_set.as_mut_ptr())));
+
+            cmd.stdin(Stdio::MakePipe);
+            cmd.stdout(Stdio::MakePipe);
+
+            let (mut cat, mut pipes) = t!(cmd.spawn(Stdio::Null, true));
+            let stdin_write = pipes.stdin.take().unwrap();
+            let stdout_read = pipes.stdout.take().unwrap();
+
+            t!(cvt(libc::pthread_sigmask(libc::SIG_SETMASK, old_set.as_ptr(), ptr::null_mut())));
+
+            t!(cvt(libc::kill(cat.id() as libc::pid_t, libc::SIGINT)));
+            // We need to wait until SIGINT is definitely delivered. The
+            // easiest way is to write something to cat, and try to read it
+            // back: if SIGINT is unmasked, it'll get delivered when cat is
+            // next scheduled.
+            let _ = stdin_write.write(b"Hello");
+            drop(stdin_write);
+
+            // Either EOF or failure (EPIPE) is okay.
+            let mut buf = [0; 5];
+            if let Ok(ret) = stdout_read.read(&mut buf) {
+                assert_eq!(ret, 0);
+            }
+
+            t!(cat.wait());
+        }
+    }
+}
diff --git a/library/std/src/sys/unix/process/process_fuchsia.rs b/library/std/src/sys/unix/process/process_fuchsia.rs
new file mode 100644
index 00000000000..6daf2885bae
--- /dev/null
+++ b/library/std/src/sys/unix/process/process_fuchsia.rs
@@ -0,0 +1,260 @@
+use crate::convert::TryInto;
+use crate::fmt;
+use crate::io;
+use crate::mem;
+use crate::ptr;
+
+use crate::sys::process::process_common::*;
+use crate::sys::process::zircon::{zx_handle_t, Handle};
+
+use libc::{c_int, size_t};
+
+////////////////////////////////////////////////////////////////////////////////
+// Command
+////////////////////////////////////////////////////////////////////////////////
+
+impl Command {
+    pub fn spawn(
+        &mut self,
+        default: Stdio,
+        needs_stdin: bool,
+    ) -> io::Result<(Process, StdioPipes)> {
+        let envp = self.capture_env();
+
+        if self.saw_nul() {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidInput,
+                "nul byte found in provided data",
+            ));
+        }
+
+        let (ours, theirs) = self.setup_io(default, needs_stdin)?;
+
+        let process_handle = unsafe { self.do_exec(theirs, envp.as_ref())? };
+
+        Ok((Process { handle: Handle::new(process_handle) }, ours))
+    }
+
+    pub fn exec(&mut self, default: Stdio) -> io::Error {
+        if self.saw_nul() {
+            return io::Error::new(io::ErrorKind::InvalidInput, "nul byte found in provided data");
+        }
+
+        match self.setup_io(default, true) {
+            Ok((_, _)) => {
+                // FIXME: This is tough because we don't support the exec syscalls
+                unimplemented!();
+            }
+            Err(e) => e,
+        }
+    }
+
+    unsafe fn do_exec(
+        &mut self,
+        stdio: ChildPipes,
+        maybe_envp: Option<&CStringArray>,
+    ) -> io::Result<zx_handle_t> {
+        use crate::sys::process::zircon::*;
+
+        let envp = match maybe_envp {
+            // None means to clone the current environment, which is done in the
+            // flags below.
+            None => ptr::null(),
+            Some(envp) => envp.as_ptr(),
+        };
+
+        let make_action = |local_io: &ChildStdio, target_fd| -> io::Result<fdio_spawn_action_t> {
+            if let Some(local_fd) = local_io.fd() {
+                Ok(fdio_spawn_action_t {
+                    action: FDIO_SPAWN_ACTION_TRANSFER_FD,
+                    local_fd,
+                    target_fd,
+                    ..Default::default()
+                })
+            } else {
+                if let ChildStdio::Null = local_io {
+                    // acts as no-op
+                    return Ok(Default::default());
+                }
+
+                let mut handle = ZX_HANDLE_INVALID;
+                let status = fdio_fd_clone(target_fd, &mut handle);
+                if status == ERR_INVALID_ARGS || status == ERR_NOT_SUPPORTED {
+                    // This descriptor is closed; skip it rather than generating an
+                    // error.
+                    return Ok(Default::default());
+                }
+                zx_cvt(status)?;
+
+                let mut cloned_fd = 0;
+                zx_cvt(fdio_fd_create(handle, &mut cloned_fd))?;
+
+                Ok(fdio_spawn_action_t {
+                    action: FDIO_SPAWN_ACTION_TRANSFER_FD,
+                    local_fd: cloned_fd as i32,
+                    target_fd,
+                    ..Default::default()
+                })
+            }
+        };
+
+        // Clone stdin, stdout, and stderr
+        let action1 = make_action(&stdio.stdin, 0)?;
+        let action2 = make_action(&stdio.stdout, 1)?;
+        let action3 = make_action(&stdio.stderr, 2)?;
+        let actions = [action1, action2, action3];
+
+        // We don't want FileDesc::drop to be called on any stdio. fdio_spawn_etc
+        // always consumes transferred file descriptors.
+        mem::forget(stdio);
+
+        for callback in self.get_closures().iter_mut() {
+            callback()?;
+        }
+
+        let mut process_handle: zx_handle_t = 0;
+        zx_cvt(fdio_spawn_etc(
+            ZX_HANDLE_INVALID,
+            FDIO_SPAWN_CLONE_JOB
+                | FDIO_SPAWN_CLONE_LDSVC
+                | FDIO_SPAWN_CLONE_NAMESPACE
+                | FDIO_SPAWN_CLONE_ENVIRON, // this is ignored when envp is non-null
+            self.get_program().as_ptr(),
+            self.get_argv().as_ptr(),
+            envp,
+            actions.len() as size_t,
+            actions.as_ptr(),
+            &mut process_handle,
+            ptr::null_mut(),
+        ))?;
+        // FIXME: See if we want to do something with that err_msg
+
+        Ok(process_handle)
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Processes
+////////////////////////////////////////////////////////////////////////////////
+
+pub struct Process {
+    handle: Handle,
+}
+
+impl Process {
+    pub fn id(&self) -> u32 {
+        self.handle.raw() as u32
+    }
+
+    pub fn kill(&mut self) -> io::Result<()> {
+        use crate::sys::process::zircon::*;
+
+        unsafe {
+            zx_cvt(zx_task_kill(self.handle.raw()))?;
+        }
+
+        Ok(())
+    }
+
+    pub fn wait(&mut self) -> io::Result<ExitStatus> {
+        use crate::default::Default;
+        use crate::sys::process::zircon::*;
+
+        let mut proc_info: zx_info_process_t = Default::default();
+        let mut actual: size_t = 0;
+        let mut avail: size_t = 0;
+
+        unsafe {
+            zx_cvt(zx_object_wait_one(
+                self.handle.raw(),
+                ZX_TASK_TERMINATED,
+                ZX_TIME_INFINITE,
+                ptr::null_mut(),
+            ))?;
+            zx_cvt(zx_object_get_info(
+                self.handle.raw(),
+                ZX_INFO_PROCESS,
+                &mut proc_info as *mut _ as *mut libc::c_void,
+                mem::size_of::<zx_info_process_t>(),
+                &mut actual,
+                &mut avail,
+            ))?;
+        }
+        if actual != 1 {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidData,
+                "Failed to get exit status of process",
+            ));
+        }
+        Ok(ExitStatus(proc_info.return_code))
+    }
+
+    pub fn try_wait(&mut self) -> io::Result<Option<ExitStatus>> {
+        use crate::default::Default;
+        use crate::sys::process::zircon::*;
+
+        let mut proc_info: zx_info_process_t = Default::default();
+        let mut actual: size_t = 0;
+        let mut avail: size_t = 0;
+
+        unsafe {
+            let status =
+                zx_object_wait_one(self.handle.raw(), ZX_TASK_TERMINATED, 0, ptr::null_mut());
+            match status {
+                0 => {} // Success
+                x if x == ERR_TIMED_OUT => {
+                    return Ok(None);
+                }
+                _ => {
+                    panic!("Failed to wait on process handle: {}", status);
+                }
+            }
+            zx_cvt(zx_object_get_info(
+                self.handle.raw(),
+                ZX_INFO_PROCESS,
+                &mut proc_info as *mut _ as *mut libc::c_void,
+                mem::size_of::<zx_info_process_t>(),
+                &mut actual,
+                &mut avail,
+            ))?;
+        }
+        if actual != 1 {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidData,
+                "Failed to get exit status of process",
+            ));
+        }
+        Ok(Some(ExitStatus(proc_info.return_code)))
+    }
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+pub struct ExitStatus(i64);
+
+impl ExitStatus {
+    pub fn success(&self) -> bool {
+        self.code() == Some(0)
+    }
+
+    pub fn code(&self) -> Option<i32> {
+        // FIXME: support extracting return code as an i64
+        self.0.try_into().ok()
+    }
+
+    pub fn signal(&self) -> Option<i32> {
+        None
+    }
+}
+
+/// Converts a raw `c_int` to a type-safe `ExitStatus` by wrapping it without copying.
+impl From<c_int> for ExitStatus {
+    fn from(a: c_int) -> ExitStatus {
+        ExitStatus(a as i64)
+    }
+}
+
+impl fmt::Display for ExitStatus {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "exit code: {}", self.0)
+    }
+}
diff --git a/library/std/src/sys/unix/process/process_unix.rs b/library/std/src/sys/unix/process/process_unix.rs
new file mode 100644
index 00000000000..0f349dfa302
--- /dev/null
+++ b/library/std/src/sys/unix/process/process_unix.rs
@@ -0,0 +1,494 @@
+use crate::convert::TryInto;
+use crate::fmt;
+use crate::io::{self, Error, ErrorKind};
+use crate::ptr;
+use crate::sys;
+use crate::sys::cvt;
+use crate::sys::process::process_common::*;
+
+use libc::{c_int, gid_t, pid_t, uid_t};
+
+////////////////////////////////////////////////////////////////////////////////
+// Command
+////////////////////////////////////////////////////////////////////////////////
+
+impl Command {
+    pub fn spawn(
+        &mut self,
+        default: Stdio,
+        needs_stdin: bool,
+    ) -> io::Result<(Process, StdioPipes)> {
+        const CLOEXEC_MSG_FOOTER: [u8; 4] = *b"NOEX";
+
+        let envp = self.capture_env();
+
+        if self.saw_nul() {
+            return Err(io::Error::new(ErrorKind::InvalidInput, "nul byte found in provided data"));
+        }
+
+        let (ours, theirs) = self.setup_io(default, needs_stdin)?;
+
+        if let Some(ret) = self.posix_spawn(&theirs, envp.as_ref())? {
+            return Ok((ret, ours));
+        }
+
+        let (input, output) = sys::pipe::anon_pipe()?;
+
+        // Whatever happens after the fork is almost for sure going to touch or
+        // look at the environment in one way or another (PATH in `execvp` or
+        // accessing the `environ` pointer ourselves). Make sure no other thread
+        // is accessing the environment when we do the fork itself.
+        //
+        // Note that as soon as we're done with the fork there's no need to hold
+        // a lock any more because the parent won't do anything and the child is
+        // in its own process.
+        let result = unsafe {
+            let _env_lock = sys::os::env_lock();
+            cvt(libc::fork())?
+        };
+
+        let pid = unsafe {
+            match result {
+                0 => {
+                    drop(input);
+                    let Err(err) = self.do_exec(theirs, envp.as_ref());
+                    let errno = err.raw_os_error().unwrap_or(libc::EINVAL) as u32;
+                    let errno = errno.to_be_bytes();
+                    let bytes = [
+                        errno[0],
+                        errno[1],
+                        errno[2],
+                        errno[3],
+                        CLOEXEC_MSG_FOOTER[0],
+                        CLOEXEC_MSG_FOOTER[1],
+                        CLOEXEC_MSG_FOOTER[2],
+                        CLOEXEC_MSG_FOOTER[3],
+                    ];
+                    // pipe I/O up to PIPE_BUF bytes should be atomic, and then
+                    // we want to be sure we *don't* run at_exit destructors as
+                    // we're being torn down regardless
+                    assert!(output.write(&bytes).is_ok());
+                    libc::_exit(1)
+                }
+                n => n,
+            }
+        };
+
+        let mut p = Process { pid, status: None };
+        drop(output);
+        let mut bytes = [0; 8];
+
+        // loop to handle EINTR
+        loop {
+            match input.read(&mut bytes) {
+                Ok(0) => return Ok((p, ours)),
+                Ok(8) => {
+                    let (errno, footer) = bytes.split_at(4);
+                    assert_eq!(
+                        CLOEXEC_MSG_FOOTER, footer,
+                        "Validation on the CLOEXEC pipe failed: {:?}",
+                        bytes
+                    );
+                    let errno = i32::from_be_bytes(errno.try_into().unwrap());
+                    assert!(p.wait().is_ok(), "wait() should either return Ok or panic");
+                    return Err(Error::from_raw_os_error(errno));
+                }
+                Err(ref e) if e.kind() == ErrorKind::Interrupted => {}
+                Err(e) => {
+                    assert!(p.wait().is_ok(), "wait() should either return Ok or panic");
+                    panic!("the CLOEXEC pipe failed: {:?}", e)
+                }
+                Ok(..) => {
+                    // pipe I/O up to PIPE_BUF bytes should be atomic
+                    assert!(p.wait().is_ok(), "wait() should either return Ok or panic");
+                    panic!("short read on the CLOEXEC pipe")
+                }
+            }
+        }
+    }
+
+    pub fn exec(&mut self, default: Stdio) -> io::Error {
+        let envp = self.capture_env();
+
+        if self.saw_nul() {
+            return io::Error::new(ErrorKind::InvalidInput, "nul byte found in provided data");
+        }
+
+        match self.setup_io(default, true) {
+            Ok((_, theirs)) => {
+                unsafe {
+                    // Similar to when forking, we want to ensure that access to
+                    // the environment is synchronized, so make sure to grab the
+                    // environment lock before we try to exec.
+                    let _lock = sys::os::env_lock();
+
+                    let Err(e) = self.do_exec(theirs, envp.as_ref());
+                    e
+                }
+            }
+            Err(e) => e,
+        }
+    }
+
+    // And at this point we've reached a special time in the life of the
+    // child. The child must now be considered hamstrung and unable to
+    // do anything other than syscalls really. Consider the following
+    // scenario:
+    //
+    //      1. Thread A of process 1 grabs the malloc() mutex
+    //      2. Thread B of process 1 forks(), creating thread C
+    //      3. Thread C of process 2 then attempts to malloc()
+    //      4. The memory of process 2 is the same as the memory of
+    //         process 1, so the mutex is locked.
+    //
+    // This situation looks a lot like deadlock, right? It turns out
+    // that this is what pthread_atfork() takes care of, which is
+    // presumably implemented across platforms. The first thing that
+    // threads to *before* forking is to do things like grab the malloc
+    // mutex, and then after the fork they unlock it.
+    //
+    // Despite this information, libnative's spawn has been witnessed to
+    // deadlock on both macOS and FreeBSD. I'm not entirely sure why, but
+    // all collected backtraces point at malloc/free traffic in the
+    // child spawned process.
+    //
+    // For this reason, the block of code below should contain 0
+    // invocations of either malloc of free (or their related friends).
+    //
+    // As an example of not having malloc/free traffic, we don't close
+    // this file descriptor by dropping the FileDesc (which contains an
+    // allocation). Instead we just close it manually. This will never
+    // have the drop glue anyway because this code never returns (the
+    // child will either exec() or invoke libc::exit)
+    unsafe fn do_exec(
+        &mut self,
+        stdio: ChildPipes,
+        maybe_envp: Option<&CStringArray>,
+    ) -> Result<!, io::Error> {
+        use crate::sys::{self, cvt_r};
+
+        if let Some(fd) = stdio.stdin.fd() {
+            cvt_r(|| libc::dup2(fd, libc::STDIN_FILENO))?;
+        }
+        if let Some(fd) = stdio.stdout.fd() {
+            cvt_r(|| libc::dup2(fd, libc::STDOUT_FILENO))?;
+        }
+        if let Some(fd) = stdio.stderr.fd() {
+            cvt_r(|| libc::dup2(fd, libc::STDERR_FILENO))?;
+        }
+
+        #[cfg(not(target_os = "l4re"))]
+        {
+            if let Some(u) = self.get_gid() {
+                cvt(libc::setgid(u as gid_t))?;
+            }
+            if let Some(u) = self.get_uid() {
+                // When dropping privileges from root, the `setgroups` call
+                // will remove any extraneous groups. If we don't call this,
+                // then even though our uid has dropped, we may still have
+                // groups that enable us to do super-user things. This will
+                // fail if we aren't root, so don't bother checking the
+                // return value, this is just done as an optimistic
+                // privilege dropping function.
+                //FIXME: Redox kernel does not support setgroups yet
+                #[cfg(not(target_os = "redox"))]
+                let _ = libc::setgroups(0, ptr::null());
+                cvt(libc::setuid(u as uid_t))?;
+            }
+        }
+        if let Some(ref cwd) = *self.get_cwd() {
+            cvt(libc::chdir(cwd.as_ptr()))?;
+        }
+
+        // emscripten has no signal support.
+        #[cfg(not(target_os = "emscripten"))]
+        {
+            use crate::mem::MaybeUninit;
+            // Reset signal handling so the child process starts in a
+            // standardized state. libstd ignores SIGPIPE, and signal-handling
+            // libraries often set a mask. Child processes inherit ignored
+            // signals and the signal mask from their parent, but most
+            // UNIX programs do not reset these things on their own, so we
+            // need to clean things up now to avoid confusing the program
+            // we're about to run.
+            let mut set = MaybeUninit::<libc::sigset_t>::uninit();
+            cvt(sigemptyset(set.as_mut_ptr()))?;
+            cvt(libc::pthread_sigmask(libc::SIG_SETMASK, set.as_ptr(), ptr::null_mut()))?;
+            let ret = sys::signal(libc::SIGPIPE, libc::SIG_DFL);
+            if ret == libc::SIG_ERR {
+                return Err(io::Error::last_os_error());
+            }
+        }
+
+        for callback in self.get_closures().iter_mut() {
+            callback()?;
+        }
+
+        // Although we're performing an exec here we may also return with an
+        // error from this function (without actually exec'ing) in which case we
+        // want to be sure to restore the global environment back to what it
+        // once was, ensuring that our temporary override, when free'd, doesn't
+        // corrupt our process's environment.
+        let mut _reset = None;
+        if let Some(envp) = maybe_envp {
+            struct Reset(*const *const libc::c_char);
+
+            impl Drop for Reset {
+                fn drop(&mut self) {
+                    unsafe {
+                        *sys::os::environ() = self.0;
+                    }
+                }
+            }
+
+            _reset = Some(Reset(*sys::os::environ()));
+            *sys::os::environ() = envp.as_ptr();
+        }
+
+        libc::execvp(self.get_program().as_ptr(), self.get_argv().as_ptr());
+        Err(io::Error::last_os_error())
+    }
+
+    #[cfg(not(any(
+        target_os = "macos",
+        target_os = "freebsd",
+        all(target_os = "linux", target_env = "gnu")
+    )))]
+    fn posix_spawn(
+        &mut self,
+        _: &ChildPipes,
+        _: Option<&CStringArray>,
+    ) -> io::Result<Option<Process>> {
+        Ok(None)
+    }
+
+    // Only support platforms for which posix_spawn() can return ENOENT
+    // directly.
+    #[cfg(any(
+        target_os = "macos",
+        target_os = "freebsd",
+        all(target_os = "linux", target_env = "gnu")
+    ))]
+    fn posix_spawn(
+        &mut self,
+        stdio: &ChildPipes,
+        envp: Option<&CStringArray>,
+    ) -> io::Result<Option<Process>> {
+        use crate::mem::MaybeUninit;
+        use crate::sys;
+
+        if self.get_gid().is_some()
+            || self.get_uid().is_some()
+            || self.env_saw_path()
+            || !self.get_closures().is_empty()
+        {
+            return Ok(None);
+        }
+
+        // Only glibc 2.24+ posix_spawn() supports returning ENOENT directly.
+        #[cfg(all(target_os = "linux", target_env = "gnu"))]
+        {
+            if let Some(version) = sys::os::glibc_version() {
+                if version < (2, 24) {
+                    return Ok(None);
+                }
+            } else {
+                return Ok(None);
+            }
+        }
+
+        // Solaris and glibc 2.29+ can set a new working directory, and maybe
+        // others will gain this non-POSIX function too. We'll check for this
+        // weak symbol as soon as it's needed, so we can return early otherwise
+        // to do a manual chdir before exec.
+        weak! {
+            fn posix_spawn_file_actions_addchdir_np(
+                *mut libc::posix_spawn_file_actions_t,
+                *const libc::c_char
+            ) -> libc::c_int
+        }
+        let addchdir = match self.get_cwd() {
+            Some(cwd) => match posix_spawn_file_actions_addchdir_np.get() {
+                Some(f) => Some((f, cwd)),
+                None => return Ok(None),
+            },
+            None => None,
+        };
+
+        let mut p = Process { pid: 0, status: None };
+
+        struct PosixSpawnFileActions(MaybeUninit<libc::posix_spawn_file_actions_t>);
+
+        impl Drop for PosixSpawnFileActions {
+            fn drop(&mut self) {
+                unsafe {
+                    libc::posix_spawn_file_actions_destroy(self.0.as_mut_ptr());
+                }
+            }
+        }
+
+        struct PosixSpawnattr(MaybeUninit<libc::posix_spawnattr_t>);
+
+        impl Drop for PosixSpawnattr {
+            fn drop(&mut self) {
+                unsafe {
+                    libc::posix_spawnattr_destroy(self.0.as_mut_ptr());
+                }
+            }
+        }
+
+        unsafe {
+            let mut file_actions = PosixSpawnFileActions(MaybeUninit::uninit());
+            let mut attrs = PosixSpawnattr(MaybeUninit::uninit());
+
+            libc::posix_spawnattr_init(attrs.0.as_mut_ptr());
+            libc::posix_spawn_file_actions_init(file_actions.0.as_mut_ptr());
+
+            if let Some(fd) = stdio.stdin.fd() {
+                cvt(libc::posix_spawn_file_actions_adddup2(
+                    file_actions.0.as_mut_ptr(),
+                    fd,
+                    libc::STDIN_FILENO,
+                ))?;
+            }
+            if let Some(fd) = stdio.stdout.fd() {
+                cvt(libc::posix_spawn_file_actions_adddup2(
+                    file_actions.0.as_mut_ptr(),
+                    fd,
+                    libc::STDOUT_FILENO,
+                ))?;
+            }
+            if let Some(fd) = stdio.stderr.fd() {
+                cvt(libc::posix_spawn_file_actions_adddup2(
+                    file_actions.0.as_mut_ptr(),
+                    fd,
+                    libc::STDERR_FILENO,
+                ))?;
+            }
+            if let Some((f, cwd)) = addchdir {
+                cvt(f(file_actions.0.as_mut_ptr(), cwd.as_ptr()))?;
+            }
+
+            let mut set = MaybeUninit::<libc::sigset_t>::uninit();
+            cvt(sigemptyset(set.as_mut_ptr()))?;
+            cvt(libc::posix_spawnattr_setsigmask(attrs.0.as_mut_ptr(), set.as_ptr()))?;
+            cvt(sigaddset(set.as_mut_ptr(), libc::SIGPIPE))?;
+            cvt(libc::posix_spawnattr_setsigdefault(attrs.0.as_mut_ptr(), set.as_ptr()))?;
+
+            let flags = libc::POSIX_SPAWN_SETSIGDEF | libc::POSIX_SPAWN_SETSIGMASK;
+            cvt(libc::posix_spawnattr_setflags(attrs.0.as_mut_ptr(), flags as _))?;
+
+            // Make sure we synchronize access to the global `environ` resource
+            let _env_lock = sys::os::env_lock();
+            let envp = envp.map(|c| c.as_ptr()).unwrap_or_else(|| *sys::os::environ() as *const _);
+            let ret = libc::posix_spawnp(
+                &mut p.pid,
+                self.get_program().as_ptr(),
+                file_actions.0.as_ptr(),
+                attrs.0.as_ptr(),
+                self.get_argv().as_ptr() as *const _,
+                envp as *const _,
+            );
+            if ret == 0 { Ok(Some(p)) } else { Err(io::Error::from_raw_os_error(ret)) }
+        }
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Processes
+////////////////////////////////////////////////////////////////////////////////
+
+/// The unique ID of the process (this should never be negative).
+pub struct Process {
+    pid: pid_t,
+    status: Option<ExitStatus>,
+}
+
+impl Process {
+    pub fn id(&self) -> u32 {
+        self.pid as u32
+    }
+
+    pub fn kill(&mut self) -> io::Result<()> {
+        // If we've already waited on this process then the pid can be recycled
+        // and used for another process, and we probably shouldn't be killing
+        // random processes, so just return an error.
+        if self.status.is_some() {
+            Err(Error::new(
+                ErrorKind::InvalidInput,
+                "invalid argument: can't kill an exited process",
+            ))
+        } else {
+            cvt(unsafe { libc::kill(self.pid, libc::SIGKILL) }).map(drop)
+        }
+    }
+
+    pub fn wait(&mut self) -> io::Result<ExitStatus> {
+        use crate::sys::cvt_r;
+        if let Some(status) = self.status {
+            return Ok(status);
+        }
+        let mut status = 0 as c_int;
+        cvt_r(|| unsafe { libc::waitpid(self.pid, &mut status, 0) })?;
+        self.status = Some(ExitStatus::new(status));
+        Ok(ExitStatus::new(status))
+    }
+
+    pub fn try_wait(&mut self) -> io::Result<Option<ExitStatus>> {
+        if let Some(status) = self.status {
+            return Ok(Some(status));
+        }
+        let mut status = 0 as c_int;
+        let pid = cvt(unsafe { libc::waitpid(self.pid, &mut status, libc::WNOHANG) })?;
+        if pid == 0 {
+            Ok(None)
+        } else {
+            self.status = Some(ExitStatus::new(status));
+            Ok(Some(ExitStatus::new(status)))
+        }
+    }
+}
+
+/// Unix exit statuses
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+pub struct ExitStatus(c_int);
+
+impl ExitStatus {
+    pub fn new(status: c_int) -> ExitStatus {
+        ExitStatus(status)
+    }
+
+    fn exited(&self) -> bool {
+        unsafe { libc::WIFEXITED(self.0) }
+    }
+
+    pub fn success(&self) -> bool {
+        self.code() == Some(0)
+    }
+
+    pub fn code(&self) -> Option<i32> {
+        if self.exited() { Some(unsafe { libc::WEXITSTATUS(self.0) }) } else { None }
+    }
+
+    pub fn signal(&self) -> Option<i32> {
+        if !self.exited() { Some(unsafe { libc::WTERMSIG(self.0) }) } else { None }
+    }
+}
+
+/// Converts a raw `c_int` to a type-safe `ExitStatus` by wrapping it without copying.
+impl From<c_int> for ExitStatus {
+    fn from(a: c_int) -> ExitStatus {
+        ExitStatus(a)
+    }
+}
+
+impl fmt::Display for ExitStatus {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if let Some(code) = self.code() {
+            write!(f, "exit code: {}", code)
+        } else {
+            let signal = self.signal().unwrap();
+            write!(f, "signal: {}", signal)
+        }
+    }
+}
diff --git a/library/std/src/sys/unix/process/zircon.rs b/library/std/src/sys/unix/process/zircon.rs
new file mode 100644
index 00000000000..750b8f0762a
--- /dev/null
+++ b/library/std/src/sys/unix/process/zircon.rs
@@ -0,0 +1,307 @@
+#![allow(non_camel_case_types, unused)]
+
+use crate::convert::TryInto;
+use crate::i64;
+use crate::io;
+use crate::mem::MaybeUninit;
+use crate::os::raw::c_char;
+
+use libc::{c_int, c_void, size_t};
+
+pub type zx_handle_t = u32;
+pub type zx_vaddr_t = usize;
+pub type zx_rights_t = u32;
+pub type zx_status_t = i32;
+
+pub const ZX_HANDLE_INVALID: zx_handle_t = 0;
+
+pub type zx_time_t = i64;
+pub const ZX_TIME_INFINITE: zx_time_t = i64::MAX;
+
+pub type zx_signals_t = u32;
+
+pub const ZX_OBJECT_SIGNAL_3: zx_signals_t = 1 << 3;
+
+pub const ZX_TASK_TERMINATED: zx_signals_t = ZX_OBJECT_SIGNAL_3;
+
+pub const ZX_RIGHT_SAME_RIGHTS: zx_rights_t = 1 << 31;
+
+pub type zx_object_info_topic_t = u32;
+
+pub const ZX_INFO_PROCESS: zx_object_info_topic_t = 3;
+
+pub fn zx_cvt<T>(t: T) -> io::Result<T>
+where
+    T: TryInto<zx_status_t> + Copy,
+{
+    if let Ok(status) = TryInto::try_into(t) {
+        if status < 0 { Err(io::Error::from_raw_os_error(status)) } else { Ok(t) }
+    } else {
+        Err(io::Error::last_os_error())
+    }
+}
+
+// Safe wrapper around zx_handle_t
+pub struct Handle {
+    raw: zx_handle_t,
+}
+
+impl Handle {
+    pub fn new(raw: zx_handle_t) -> Handle {
+        Handle { raw }
+    }
+
+    pub fn raw(&self) -> zx_handle_t {
+        self.raw
+    }
+}
+
+impl Drop for Handle {
+    fn drop(&mut self) {
+        unsafe {
+            zx_cvt(zx_handle_close(self.raw)).expect("Failed to close zx_handle_t");
+        }
+    }
+}
+
+// Returned for topic ZX_INFO_PROCESS
+#[derive(Default)]
+#[repr(C)]
+pub struct zx_info_process_t {
+    pub return_code: i64,
+    pub started: bool,
+    pub exited: bool,
+    pub debugger_attached: bool,
+}
+
+extern "C" {
+    pub fn zx_job_default() -> zx_handle_t;
+
+    pub fn zx_task_kill(handle: zx_handle_t) -> zx_status_t;
+
+    pub fn zx_handle_close(handle: zx_handle_t) -> zx_status_t;
+
+    pub fn zx_handle_duplicate(
+        handle: zx_handle_t,
+        rights: zx_rights_t,
+        out: *const zx_handle_t,
+    ) -> zx_handle_t;
+
+    pub fn zx_object_wait_one(
+        handle: zx_handle_t,
+        signals: zx_signals_t,
+        timeout: zx_time_t,
+        pending: *mut zx_signals_t,
+    ) -> zx_status_t;
+
+    pub fn zx_object_get_info(
+        handle: zx_handle_t,
+        topic: u32,
+        buffer: *mut c_void,
+        buffer_size: size_t,
+        actual_size: *mut size_t,
+        avail: *mut size_t,
+    ) -> zx_status_t;
+}
+
+#[derive(Default)]
+#[repr(C)]
+pub struct fdio_spawn_action_t {
+    pub action: u32,
+    pub reserved0: u32,
+    pub local_fd: i32,
+    pub target_fd: i32,
+    pub reserved1: u64,
+}
+
+extern "C" {
+    pub fn fdio_spawn_etc(
+        job: zx_handle_t,
+        flags: u32,
+        path: *const c_char,
+        argv: *const *const c_char,
+        envp: *const *const c_char,
+        action_count: size_t,
+        actions: *const fdio_spawn_action_t,
+        process: *mut zx_handle_t,
+        err_msg: *mut c_char,
+    ) -> zx_status_t;
+
+    pub fn fdio_fd_clone(fd: c_int, out_handle: *mut zx_handle_t) -> zx_status_t;
+    pub fn fdio_fd_create(handle: zx_handle_t, fd: *mut c_int) -> zx_status_t;
+}
+
+// fdio_spawn_etc flags
+
+pub const FDIO_SPAWN_CLONE_JOB: u32 = 0x0001;
+pub const FDIO_SPAWN_CLONE_LDSVC: u32 = 0x0002;
+pub const FDIO_SPAWN_CLONE_NAMESPACE: u32 = 0x0004;
+pub const FDIO_SPAWN_CLONE_STDIO: u32 = 0x0008;
+pub const FDIO_SPAWN_CLONE_ENVIRON: u32 = 0x0010;
+pub const FDIO_SPAWN_CLONE_ALL: u32 = 0xFFFF;
+
+// fdio_spawn_etc actions
+
+pub const FDIO_SPAWN_ACTION_CLONE_FD: u32 = 0x0001;
+pub const FDIO_SPAWN_ACTION_TRANSFER_FD: u32 = 0x0002;
+
+// Errors
+
+#[allow(unused)]
+pub const ERR_INTERNAL: zx_status_t = -1;
+
+// ERR_NOT_SUPPORTED: The operation is not implemented, supported,
+// or enabled.
+#[allow(unused)]
+pub const ERR_NOT_SUPPORTED: zx_status_t = -2;
+
+// ERR_NO_RESOURCES: The system was not able to allocate some resource
+// needed for the operation.
+#[allow(unused)]
+pub const ERR_NO_RESOURCES: zx_status_t = -3;
+
+// ERR_NO_MEMORY: The system was not able to allocate memory needed
+// for the operation.
+#[allow(unused)]
+pub const ERR_NO_MEMORY: zx_status_t = -4;
+
+// ERR_CALL_FAILED: The second phase of zx_channel_call(; did not complete
+// successfully.
+#[allow(unused)]
+pub const ERR_CALL_FAILED: zx_status_t = -5;
+
+// ERR_INTERRUPTED_RETRY: The system call was interrupted, but should be
+// retried.  This should not be seen outside of the VDSO.
+#[allow(unused)]
+pub const ERR_INTERRUPTED_RETRY: zx_status_t = -6;
+
+// ======= Parameter errors =======
+// ERR_INVALID_ARGS: an argument is invalid, ex. null pointer
+#[allow(unused)]
+pub const ERR_INVALID_ARGS: zx_status_t = -10;
+
+// ERR_BAD_HANDLE: A specified handle value does not refer to a handle.
+#[allow(unused)]
+pub const ERR_BAD_HANDLE: zx_status_t = -11;
+
+// ERR_WRONG_TYPE: The subject of the operation is the wrong type to
+// perform the operation.
+// Example: Attempting a message_read on a thread handle.
+#[allow(unused)]
+pub const ERR_WRONG_TYPE: zx_status_t = -12;
+
+// ERR_BAD_SYSCALL: The specified syscall number is invalid.
+#[allow(unused)]
+pub const ERR_BAD_SYSCALL: zx_status_t = -13;
+
+// ERR_OUT_OF_RANGE: An argument is outside the valid range for this
+// operation.
+#[allow(unused)]
+pub const ERR_OUT_OF_RANGE: zx_status_t = -14;
+
+// ERR_BUFFER_TOO_SMALL: A caller provided buffer is too small for
+// this operation.
+#[allow(unused)]
+pub const ERR_BUFFER_TOO_SMALL: zx_status_t = -15;
+
+// ======= Precondition or state errors =======
+// ERR_BAD_STATE: operation failed because the current state of the
+// object does not allow it, or a precondition of the operation is
+// not satisfied
+#[allow(unused)]
+pub const ERR_BAD_STATE: zx_status_t = -20;
+
+// ERR_TIMED_OUT: The time limit for the operation elapsed before
+// the operation completed.
+#[allow(unused)]
+pub const ERR_TIMED_OUT: zx_status_t = -21;
+
+// ERR_SHOULD_WAIT: The operation cannot be performed currently but
+// potentially could succeed if the caller waits for a prerequisite
+// to be satisfied, for example waiting for a handle to be readable
+// or writable.
+// Example: Attempting to read from a message pipe that has no
+// messages waiting but has an open remote will return ERR_SHOULD_WAIT.
+// Attempting to read from a message pipe that has no messages waiting
+// and has a closed remote end will return ERR_REMOTE_CLOSED.
+#[allow(unused)]
+pub const ERR_SHOULD_WAIT: zx_status_t = -22;
+
+// ERR_CANCELED: The in-progress operation (e.g., a wait) has been
+// // canceled.
+#[allow(unused)]
+pub const ERR_CANCELED: zx_status_t = -23;
+
+// ERR_PEER_CLOSED: The operation failed because the remote end
+// of the subject of the operation was closed.
+#[allow(unused)]
+pub const ERR_PEER_CLOSED: zx_status_t = -24;
+
+// ERR_NOT_FOUND: The requested entity is not found.
+#[allow(unused)]
+pub const ERR_NOT_FOUND: zx_status_t = -25;
+
+// ERR_ALREADY_EXISTS: An object with the specified identifier
+// already exists.
+// Example: Attempting to create a file when a file already exists
+// with that name.
+#[allow(unused)]
+pub const ERR_ALREADY_EXISTS: zx_status_t = -26;
+
+// ERR_ALREADY_BOUND: The operation failed because the named entity
+// is already owned or controlled by another entity. The operation
+// could succeed later if the current owner releases the entity.
+#[allow(unused)]
+pub const ERR_ALREADY_BOUND: zx_status_t = -27;
+
+// ERR_UNAVAILABLE: The subject of the operation is currently unable
+// to perform the operation.
+// Note: This is used when there's no direct way for the caller to
+// observe when the subject will be able to perform the operation
+// and should thus retry.
+#[allow(unused)]
+pub const ERR_UNAVAILABLE: zx_status_t = -28;
+
+// ======= Permission check errors =======
+// ERR_ACCESS_DENIED: The caller did not have permission to perform
+// the specified operation.
+#[allow(unused)]
+pub const ERR_ACCESS_DENIED: zx_status_t = -30;
+
+// ======= Input-output errors =======
+// ERR_IO: Otherwise unspecified error occurred during I/O.
+#[allow(unused)]
+pub const ERR_IO: zx_status_t = -40;
+
+// ERR_REFUSED: The entity the I/O operation is being performed on
+// rejected the operation.
+// Example: an I2C device NAK'ing a transaction or a disk controller
+// rejecting an invalid command.
+#[allow(unused)]
+pub const ERR_IO_REFUSED: zx_status_t = -41;
+
+// ERR_IO_DATA_INTEGRITY: The data in the operation failed an integrity
+// check and is possibly corrupted.
+// Example: CRC or Parity error.
+#[allow(unused)]
+pub const ERR_IO_DATA_INTEGRITY: zx_status_t = -42;
+
+// ERR_IO_DATA_LOSS: The data in the operation is currently unavailable
+// and may be permanently lost.
+// Example: A disk block is irrecoverably damaged.
+#[allow(unused)]
+pub const ERR_IO_DATA_LOSS: zx_status_t = -43;
+
+// Filesystem specific errors
+#[allow(unused)]
+pub const ERR_BAD_PATH: zx_status_t = -50;
+#[allow(unused)]
+pub const ERR_NOT_DIR: zx_status_t = -51;
+#[allow(unused)]
+pub const ERR_NOT_FILE: zx_status_t = -52;
+// ERR_FILE_BIG: A file exceeds a filesystem-specific size limit.
+#[allow(unused)]
+pub const ERR_FILE_BIG: zx_status_t = -53;
+// ERR_NO_SPACE: Filesystem or device space is exhausted.
+#[allow(unused)]
+pub const ERR_NO_SPACE: zx_status_t = -54;