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    //! An interface for controlling asynchronous communication ports
    //!
    //! This interface provides a safe wrapper around the termios subsystem defined by POSIX. The
    //! underlying types are all implemented in libc for most platforms and either wrapped in safer
    //! types here or exported directly.
    //!
    //! If you are unfamiliar with the `termios` API, you should first read the
    //! [API documentation](http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/termios.h.html) and
    //! then come back to understand how `nix` safely wraps it.
    //!
    //! It should be noted that this API incurs some runtime overhead above the base `libc` definitions.
    //! As this interface is not used with high-bandwidth information, this should be fine in most
    //! cases. The primary cost when using this API is that the `Termios` datatype here duplicates the
    //! standard fields of the underlying `termios` struct and uses safe type wrappers for those fields.
    //! This means that when crossing the FFI interface to the underlying C library, data is first
    //! copied into the underlying `termios` struct, then the operation is done, and the data is copied
    //! back (with additional sanity checking) into the safe wrapper types. The `termios` struct is
    //! relatively small across all platforms (on the order of 32-64 bytes).
    //!
    //! The following examples highlight some of the API use cases such that users coming from using C
    //! or reading the standard documentation will understand how to use the safe API exposed here.
    //!
    //! Example disabling processing of the end-of-file control character:
    //!
    //! ```
    //! # use self::nix::sys::termios::SpecialCharacterIndices::VEOF;
    //! # use self::nix::sys::termios::{_POSIX_VDISABLE, Termios};
    //! # let mut termios = unsafe { Termios::default_uninit() };
    //! termios.control_chars[VEOF as usize] = _POSIX_VDISABLE;
    //! ```
    //!
    //! The flags within `Termios` are defined as bitfields using the `bitflags` crate. This provides
    //! an interface for working with bitfields that is similar to working with the raw unsigned
    //! integer types but offers type safety because of the internal checking that values will always
    //! be a valid combination of the defined flags.
    //!
    //! An example showing some of the basic operations for interacting with the control flags:
    //!
    //! ```
    //! # use self::nix::sys::termios::{ControlFlags, Termios};
    //! # let mut termios = unsafe { Termios::default_uninit() };
    //! termios.control_flags & ControlFlags::CSIZE == ControlFlags::CS5;
    //! termios.control_flags |= ControlFlags::CS5;
    //! ```
    //!
    //! # Baud rates
    //!
    //! This API is not consistent across platforms when it comes to `BaudRate`: Android and Linux both
    //! only support the rates specified by the `BaudRate` enum through their termios API while the BSDs
    //! support arbitrary baud rates as the values of the `BaudRate` enum constants are the same integer
    //! value of the constant (`B9600` == `9600`). Therefore the `nix::termios` API uses the following
    //! conventions:
    //!
    //! * `cfgetispeed()` - Returns `u32` on BSDs, `BaudRate` on Android/Linux
    //! * `cfgetospeed()` - Returns `u32` on BSDs, `BaudRate` on Android/Linux
    //! * `cfsetispeed()` - Takes `u32` or `BaudRate` on BSDs, `BaudRate` on Android/Linux
    //! * `cfsetospeed()` - Takes `u32` or `BaudRate` on BSDs, `BaudRate` on Android/Linux
    //! * `cfsetspeed()` - Takes `u32` or `BaudRate` on BSDs, `BaudRate` on Android/Linux
    //!
    //! The most common use case of specifying a baud rate using the enum will work the same across
    //! platforms:
    //!
    //! ```rust
    //! # #[macro_use] extern crate nix;
    //! # use nix::sys::termios::{BaudRate, cfsetispeed, cfsetospeed, cfsetspeed, Termios};
    //! # fn main() {
    //! # let mut t = unsafe { Termios::default_uninit() };
    //! cfsetispeed(&mut t, BaudRate::B9600);
    //! cfsetospeed(&mut t, BaudRate::B9600);
    //! cfsetspeed(&mut t, BaudRate::B9600);
    //! # }
    //! ```
    //!
    //! Additionally round-tripping baud rates is consistent across platforms:
    //!
    //! ```rust
    //! # extern crate nix;
    //! # use nix::sys::termios::{BaudRate, cfgetispeed, cfgetospeed, cfsetispeed, cfsetspeed, Termios};
    //! # fn main() {
    //! # let mut t = unsafe { Termios::default_uninit() };
    //! # cfsetspeed(&mut t, BaudRate::B9600);
    //! let speed = cfgetispeed(&t);
    //! assert!(speed == cfgetospeed(&t));
    //! cfsetispeed(&mut t, speed);
    //! # }
    //! ```
    //!
    //! On non-BSDs, `cfgetispeed()` and `cfgetospeed()` both return a `BaudRate`:
    //!
    // FIXME: Replace `ignore` with `compile_fail` once 1.22 is the minimum support Rust version
    #![cfg_attr(any(target_os = "freebsd", target_os = "dragonfly", target_os = "ios",
                    target_os = "macos", target_os = "netbsd", target_os = "openbsd"),
                doc = " ```rust,ignore")]
    #![cfg_attr(not(any(target_os = "freebsd", target_os = "dragonfly", target_os = "ios",
                        target_os = "macos", target_os = "netbsd", target_os = "openbsd")),
                doc = " ```rust")]
    //! # extern crate nix;
    //! # use nix::sys::termios::{BaudRate, cfgetispeed, cfgetospeed, cfsetspeed, Termios};
    //! # fn main() {
    //! # let mut t = unsafe { Termios::default_uninit() };
    //! # cfsetspeed(&mut t, BaudRate::B9600);
    //! assert!(cfgetispeed(&t) == BaudRate::B9600);
    //! assert!(cfgetospeed(&t) == BaudRate::B9600);
    //! # }
    //! ```
    //!
    //! But on the BSDs, `cfgetispeed()` and `cfgetospeed()` both return `u32`s:
    //!
    // FIXME: Replace `ignore` with `compile_fail` once 1.22 is the minimum support Rust version
    #![cfg_attr(any(target_os = "freebsd", target_os = "dragonfly", target_os = "ios",
                    target_os = "macos", target_os = "netbsd", target_os = "openbsd"),
                doc = " ```rust")]
    #![cfg_attr(not(any(target_os = "freebsd", target_os = "dragonfly", target_os = "ios",
                        target_os = "macos", target_os = "netbsd", target_os = "openbsd")),
                doc = " ```rust,ignore")]
    //! # extern crate nix;
    //! # use nix::sys::termios::{BaudRate, cfgetispeed, cfgetospeed, cfsetspeed, Termios};
    //! # fn main() {
    //! # let mut t = unsafe { Termios::default_uninit() };
    //! # cfsetspeed(&mut t, 9600u32);
    //! assert!(cfgetispeed(&t) == 9600u32);
    //! assert!(cfgetospeed(&t) == 9600u32);
    //! # }
    //! ```
    //!
    //! It's trivial to convert from a `BaudRate` to a `u32` on BSDs:
    //!
    // FIXME: Replace `ignore` with `compile_fail` once 1.22 is the minimum support Rust version
    #![cfg_attr(any(target_os = "freebsd", target_os = "dragonfly", target_os = "ios",
                    target_os = "macos", target_os = "netbsd", target_os = "openbsd"),
                doc = " ```rust")]
    #![cfg_attr(not(any(target_os = "freebsd", target_os = "dragonfly", target_os = "ios",
                        target_os = "macos", target_os = "netbsd", target_os = "openbsd")),
                doc = " ```rust,ignore")]
    //! # extern crate nix;
    //! # use nix::sys::termios::{BaudRate, cfgetispeed, cfsetspeed, Termios};
    //! # fn main() {
    //! # let mut t = unsafe { Termios::default_uninit() };
    //! # cfsetspeed(&mut t, 9600u32);
    //! assert!(cfgetispeed(&t) == BaudRate::B9600.into());
    //! assert!(u32::from(BaudRate::B9600) == 9600u32);
    //! # }
    //! ```
    //!
    //! And on BSDs you can specify arbitrary baud rates (**note** this depends on hardware support)
    //! by specifying baud rates directly using `u32`s:
    //!
    // FIXME: Replace `ignore` with `compile_fail` once 1.22 is the minimum support Rust version
    #![cfg_attr(any(target_os = "freebsd", target_os = "dragonfly", target_os = "ios",
                    target_os = "macos", target_os = "netbsd", target_os = "openbsd"),
                doc = " ```rust")]
    #![cfg_attr(not(any(target_os = "freebsd", target_os = "dragonfly", target_os = "ios",
                        target_os = "macos", target_os = "netbsd", target_os = "openbsd")),
                doc = " ```rust,ignore")]
    //! # extern crate nix;
    //! # use nix::sys::termios::{cfsetispeed, cfsetospeed, cfsetspeed, Termios};
    //! # fn main() {
    //! # let mut t = unsafe { Termios::default_uninit() };
    //! cfsetispeed(&mut t, 9600u32);
    //! cfsetospeed(&mut t, 9600u32);
    //! cfsetspeed(&mut t, 9600u32);
    //! # }
    //! ```
    use Result;
    use errno::Errno;
    use libc::{self, c_int, tcflag_t};
    use std::cell::{Ref, RefCell};
    use std::convert::From;
    use std::mem;
    use std::os::unix::io::RawFd;

    use ::unistd::Pid;

    /// Stores settings for the termios API
    ///
    /// This is a wrapper around the `libc::termios` struct that provides a safe interface for the
    /// standard fields. The only safe way to obtain an instance of this struct is to extract it from
    /// an open port using `tcgetattr()`.
    #[derive(Clone)]
    #[allow(missing_debug_implementations)]
    pub struct Termios {
        inner: RefCell<libc::termios>,
        /// Input mode flags (see `termios.c_iflag` documentation)
        pub input_flags: InputFlags,
        /// Output mode flags (see `termios.c_oflag` documentation)
        pub output_flags: OutputFlags,
        /// Control mode flags (see `termios.c_cflag` documentation)
        pub control_flags: ControlFlags,
        /// Local mode flags (see `termios.c_lflag` documentation)
        pub local_flags: LocalFlags,
        /// Control characters (see `termios.c_cc` documentation)
        pub control_chars: [libc::cc_t; NCCS],
    }

    impl Termios {
        /// Exposes an immutable reference to the underlying `libc::termios` data structure.
        ///
        /// This can be used for interfacing with other FFI functions like:
        ///
        /// ```rust
        /// # extern crate libc;
        /// # extern crate nix;
        /// # fn main() {
        /// # use nix::sys::termios::Termios;
        /// # let mut termios = unsafe { Termios::default_uninit() };
        /// let inner_termios = termios.get_libc_termios();
        /// unsafe { libc::cfgetispeed(&*inner_termios) };
        /// # }
        /// ```
        ///
        /// There is no public API exposed for functions that modify the underlying `libc::termios`
        /// data because it requires additional work to maintain type safety.
        // FIXME: Switch this over to use pub(crate)
        #[doc(hidden)]
        pub fn get_libc_termios(&self) -> Ref<libc::termios> {
            {
                let mut termios = self.inner.borrow_mut();
                termios.c_iflag = self.input_flags.bits();
                termios.c_oflag = self.output_flags.bits();
                termios.c_cflag = self.control_flags.bits();
                termios.c_lflag = self.local_flags.bits();
                termios.c_cc = self.control_chars;
            }
            self.inner.borrow()
        }

        /// Exposes the inner `libc::termios` datastore within `Termios`.
        ///
        /// This is unsafe because if this is used to modify the inner libc::termios struct, it will not
        /// automatically update the safe wrapper type around it. Therefore we disable docs to
        /// effectively limit its use to nix internals. In this case it should also be paired with a
        /// call to `update_wrapper()` so that the wrapper-type and internal representation stay
        /// consistent.
        unsafe fn get_libc_termios_mut(&mut self) -> *mut libc::termios {
            {
                let mut termios = self.inner.borrow_mut();
                termios.c_iflag = self.input_flags.bits();
                termios.c_oflag = self.output_flags.bits();
                termios.c_cflag = self.control_flags.bits();
                termios.c_lflag = self.local_flags.bits();
                termios.c_cc = self.control_chars;
            }
            self.inner.as_ptr()
        }

        /// Allows for easily creating new `Termios` structs that will be overwritten with real data.
        ///
        /// This should only be used when the inner libc::termios struct will be overwritten before it's
        /// read.
        // FIXME: Switch this over to use pub(crate)
        #[doc(hidden)]
        pub unsafe fn default_uninit() -> Self {
            Termios {
                inner: RefCell::new(mem::uninitialized()),
                input_flags: InputFlags::empty(),
                output_flags: OutputFlags::empty(),
                control_flags: ControlFlags::empty(),
                local_flags: LocalFlags::empty(),
                control_chars: [0 as libc::cc_t; NCCS],
            }
        }

        /// Updates the wrapper values from the internal `libc::termios` data structure.
        #[doc(hidden)]
        pub fn update_wrapper(&mut self) {
            let termios = *self.inner.borrow_mut();
            self.input_flags = InputFlags::from_bits_truncate(termios.c_iflag);
            self.output_flags = OutputFlags::from_bits_truncate(termios.c_oflag);
            self.control_flags = ControlFlags::from_bits_truncate(termios.c_cflag);
            self.local_flags = LocalFlags::from_bits_truncate(termios.c_lflag);
            self.control_chars = termios.c_cc;
        }
    }

    impl From<libc::termios> for Termios {
        fn from(termios: libc::termios) -> Self {
            Termios {
                inner: RefCell::new(termios),
                input_flags: InputFlags::from_bits_truncate(termios.c_iflag),
                output_flags: OutputFlags::from_bits_truncate(termios.c_oflag),
                control_flags: ControlFlags::from_bits_truncate(termios.c_cflag),
                local_flags: LocalFlags::from_bits_truncate(termios.c_lflag),
                control_chars: termios.c_cc,
            }
        }
    }

    impl From<Termios> for libc::termios {
        fn from(termios: Termios) -> Self {
            termios.inner.into_inner()
        }
    }

    libc_enum!{
        /// Baud rates supported by the system.
        ///
        /// For the BSDs, arbitrary baud rates can be specified by using `u32`s directly instead of this
        /// enum.
        ///
        /// B0 is special and will disable the port.
        #[cfg_attr(all(any(target_os = "ios", target_os = "macos"), target_pointer_width = "64"), repr(u64))]
        #[cfg_attr(not(all(any(target_os = "ios", target_os = "macos"), target_pointer_width = "64")), repr(u32))]
        pub enum BaudRate {
            B0,
            B50,
            B75,
            B110,
            B134,
            B150,
            B200,
            B300,
            B600,
            B1200,
            B1800,
            B2400,
            B4800,
            #[cfg(any(target_os = "dragonfly",
                    target_os = "freebsd",
                    target_os = "macos",
                    target_os = "netbsd",
                    target_os = "openbsd"))]
            B7200,
            B9600,
            #[cfg(any(target_os = "dragonfly",
                    target_os = "freebsd",
                    target_os = "macos",
                    target_os = "netbsd",
                    target_os = "openbsd"))]
            B14400,
            B19200,
            #[cfg(any(target_os = "dragonfly",
                    target_os = "freebsd",
                    target_os = "macos",
                    target_os = "netbsd",
                    target_os = "openbsd"))]
            B28800,
            B38400,
            B57600,
            #[cfg(any(target_os = "dragonfly",
                    target_os = "freebsd",
                    target_os = "macos",
                    target_os = "netbsd",
                    target_os = "openbsd"))]
            B76800,
            B115200,
            B230400,
            #[cfg(any(target_os = "android",
                      target_os = "freebsd",
                      target_os = "linux",
                      target_os = "netbsd"))]
            B460800,
            #[cfg(any(target_os = "android", target_os = "linux"))]
            B500000,
            #[cfg(any(target_os = "android", target_os = "linux"))]
            B576000,
            #[cfg(any(target_os = "android",
                      target_os = "freebsd",
                      target_os = "linux",
                      target_os = "netbsd"))]
            B921600,
            #[cfg(any(target_os = "android", target_os = "linux"))]
            B1000000,
            #[cfg(any(target_os = "android", target_os = "linux"))]
            B1152000,
            #[cfg(any(target_os = "android", target_os = "linux"))]
            B1500000,
            #[cfg(any(target_os = "android", target_os = "linux"))]
            B2000000,
            #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "sparc64"))))]
            B2500000,
            #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "sparc64"))))]
            B3000000,
            #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "sparc64"))))]
            B3500000,
            #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "sparc64"))))]
            B4000000,
        }
    }

    impl From<libc::speed_t> for BaudRate {
        fn from(s: libc::speed_t) -> BaudRate {

            use libc::{B0, B50, B75, B110, B134, B150, B200, B300, B600, B1200, B1800, B2400, B4800,
                       B9600, B19200, B38400, B57600, B115200, B230400};
            #[cfg(any(target_os = "android", target_os = "linux"))]
            use libc::{B500000, B576000, B1000000, B1152000, B1500000, B2000000};
            #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "sparc64"))))]
            use libc::{B2500000, B3000000, B3500000, B4000000};
            #[cfg(any(target_os = "dragonfly",
                      target_os = "freebsd",
                      target_os = "macos",
                      target_os = "netbsd",
                      target_os = "openbsd"))]
            use libc::{B7200, B14400, B28800, B76800};
            #[cfg(any(target_os = "android",
                      target_os = "freebsd",
                      target_os = "linux",
                      target_os = "netbsd"))]
            use libc::{B460800, B921600};

            match s {
                B0 => BaudRate::B0,
                B50 => BaudRate::B50,
                B75 => BaudRate::B75,
                B110 => BaudRate::B110,
                B134 => BaudRate::B134,
                B150 => BaudRate::B150,
                B200 => BaudRate::B200,
                B300 => BaudRate::B300,
                B600 => BaudRate::B600,
                B1200 => BaudRate::B1200,
                B1800 => BaudRate::B1800,
                B2400 => BaudRate::B2400,
                B4800 => BaudRate::B4800,
                #[cfg(any(target_os = "dragonfly",
                          target_os = "freebsd",
                          target_os = "macos",
                          target_os = "netbsd",
                          target_os = "openbsd"))]
                B7200 => BaudRate::B7200,
                B9600 => BaudRate::B9600,
                #[cfg(any(target_os = "dragonfly",
                          target_os = "freebsd",
                          target_os = "macos",
                          target_os = "netbsd",
                          target_os = "openbsd"))]
                B14400 => BaudRate::B14400,
                B19200 => BaudRate::B19200,
                #[cfg(any(target_os = "dragonfly",
                          target_os = "freebsd",
                          target_os = "macos",
                          target_os = "netbsd",
                          target_os = "openbsd"))]
                B28800 => BaudRate::B28800,
                B38400 => BaudRate::B38400,
                B57600 => BaudRate::B57600,
                #[cfg(any(target_os = "dragonfly",
                          target_os = "freebsd",
                          target_os = "macos",
                          target_os = "netbsd",
                          target_os = "openbsd"))]
                B76800 => BaudRate::B76800,
                B115200 => BaudRate::B115200,
                B230400 => BaudRate::B230400,
                #[cfg(any(target_os = "android",
                          target_os = "freebsd",
                          target_os = "linux",
                          target_os = "netbsd"))]
                B460800 => BaudRate::B460800,
                #[cfg(any(target_os = "android", target_os = "linux"))]
                B500000 => BaudRate::B500000,
                #[cfg(any(target_os = "android", target_os = "linux"))]
                B576000 => BaudRate::B576000,
                #[cfg(any(target_os = "android",
                          target_os = "freebsd",
                          target_os = "linux",
                          target_os = "netbsd"))]
                B921600 => BaudRate::B921600,
                #[cfg(any(target_os = "android", target_os = "linux"))]
                B1000000 => BaudRate::B1000000,
                #[cfg(any(target_os = "android", target_os = "linux"))]
                B1152000 => BaudRate::B1152000,
                #[cfg(any(target_os = "android", target_os = "linux"))]
                B1500000 => BaudRate::B1500000,
                #[cfg(any(target_os = "android", target_os = "linux"))]
                B2000000 => BaudRate::B2000000,
                #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "sparc64"))))]
                B2500000 => BaudRate::B2500000,
                #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "sparc64"))))]
                B3000000 => BaudRate::B3000000,
                #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "sparc64"))))]
                B3500000 => BaudRate::B3500000,
                #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "sparc64"))))]
                B4000000 => BaudRate::B4000000,
                b => unreachable!("Invalid baud constant: {}", b),
            }
        }
    }

    // TODO: Include `TryFrom<u32> for BaudRate` once that API stabilizes
    #[cfg(any(target_os = "freebsd",
              target_os = "dragonfly",
              target_os = "ios",
              target_os = "macos",
              target_os = "netbsd",
              target_os = "openbsd"))]
    impl From<BaudRate> for u32 {
        fn from(b: BaudRate) -> u32 {
            b as u32
        }
    }

    // TODO: Add TCSASOFT, which will require treating this as a bitfield.
    libc_enum! {
        /// Specify when a port configuration change should occur.
        ///
        /// Used as an argument to `tcsetattr()`
        #[repr(i32)]
        pub enum SetArg {
            /// The change will occur immediately
            TCSANOW,
            /// The change occurs after all output has been written
            TCSADRAIN,
            /// Same as `TCSADRAIN`, but will also flush the input buffer
            TCSAFLUSH,
        }
    }

    libc_enum! {
        /// Specify a combination of the input and output buffers to flush
        ///
        /// Used as an argument to `tcflush()`.
        #[repr(i32)]
        pub enum FlushArg {
            /// Flush data that was received but not read
            TCIFLUSH,
            /// Flush data written but not transmitted
            TCOFLUSH,
            /// Flush both received data not read and written data not transmitted
            TCIOFLUSH,
        }
    }

    libc_enum! {
        /// Specify how transmission flow should be altered
        ///
        /// Used as an argument to `tcflow()`.
        #[repr(i32)]
        pub enum FlowArg {
            /// Suspend transmission
            TCOOFF,
            /// Resume transmission
            TCOON,
            /// Transmit a STOP character, which should disable a connected terminal device
            TCIOFF,
            /// Transmit a START character, which should re-enable a connected terminal device
            TCION,
        }
    }

    // TODO: Make this usable directly as a slice index.
    libc_enum! {
        /// Indices into the `termios.c_cc` array for special characters.
        #[repr(usize)]
        pub enum SpecialCharacterIndices {
            VDISCARD,
            #[cfg(any(target_os = "dragonfly",
                    target_os = "freebsd",
                    target_os = "macos",
                    target_os = "netbsd",
                    target_os = "openbsd"))]
            VDSUSP,
            VEOF,
            VEOL,
            VEOL2,
            VERASE,
            #[cfg(any(target_os = "dragonfly", target_os = "freebsd"))]
            VERASE2,
            VINTR,
            VKILL,
            VLNEXT,
            #[cfg(not(all(target_os = "linux", target_arch = "sparc64")))]
            VMIN,
            VQUIT,
            VREPRINT,
            VSTART,
            #[cfg(any(target_os = "dragonfly",
                    target_os = "freebsd",
                    target_os = "macos",
                    target_os = "netbsd",
                    target_os = "openbsd"))]
            VSTATUS,
            VSTOP,
            VSUSP,
            #[cfg(target_os = "linux")]
            VSWTC,
            #[cfg(target_os = "haiku")]
            VSWTCH,
            #[cfg(not(all(target_os = "linux", target_arch = "sparc64")))]
            VTIME,
            VWERASE,
            #[cfg(target_os = "dragonfly")]
            VCHECKPT,
        }
    }

    pub use libc::NCCS;
    #[cfg(any(target_os = "dragonfly",
              target_os = "freebsd",
              target_os = "linux",
              target_os = "macos",
              target_os = "netbsd",
              target_os = "openbsd"))]
    pub use libc::_POSIX_VDISABLE;

    libc_bitflags! {
        /// Flags for configuring the input mode of a terminal
        pub struct InputFlags: tcflag_t {
            IGNBRK;
            BRKINT;
            IGNPAR;
            PARMRK;
            INPCK;
            ISTRIP;
            INLCR;
            IGNCR;
            ICRNL;
            IXON;
            IXOFF;
            IXANY;
            IMAXBEL;
            #[cfg(any(target_os = "android", target_os = "linux", target_os = "macos"))]
            IUTF8;
        }
    }

    libc_bitflags! {
        /// Flags for configuring the output mode of a terminal
        pub struct OutputFlags: tcflag_t {
            OPOST;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "linux",
                      target_os = "openbsd"))]
            OLCUC;
            ONLCR;
            OCRNL as tcflag_t;
            ONOCR as tcflag_t;
            ONLRET as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            OFILL as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            OFDEL as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            NL0 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            NL1 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            CR0 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            CR1 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            CR2 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            CR3 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "freebsd",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            TAB0 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            TAB1 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            TAB2 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "freebsd",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            TAB3 as tcflag_t;
            #[cfg(any(target_os = "android", target_os = "linux"))]
            XTABS;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            BS0 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            BS1 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            VT0 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            VT1 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            FF0 as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            FF1 as tcflag_t;
            #[cfg(any(target_os = "freebsd",
                      target_os = "dragonfly",
                      target_os = "ios",
                      target_os = "macos",
                      target_os = "netbsd",
                      target_os = "openbsd"))]
            OXTABS;
            #[cfg(any(target_os = "freebsd",
                      target_os = "dragonfly",
                      target_os = "macos",
                      target_os = "netbsd",
                      target_os = "openbsd"))]
            ONOEOT as tcflag_t;

            // Bitmasks for use with OutputFlags to select specific settings
            // These should be moved to be a mask once https://github.com/rust-lang-nursery/bitflags/issues/110
            // is resolved.

            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            NLDLY as tcflag_t; // FIXME: Datatype needs to be corrected in libc for mac
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            CRDLY as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "freebsd",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            TABDLY as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            BSDLY as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            VTDLY as tcflag_t;
            #[cfg(any(target_os = "android",
                      target_os = "haiku",
                      target_os = "ios",
                      target_os = "linux",
                      target_os = "macos"))]
            FFDLY as tcflag_t;
        }
    }

    libc_bitflags! {
        /// Flags for setting the control mode of a terminal
        pub struct ControlFlags: tcflag_t {
            #[cfg(any(target_os = "dragonfly",
                      target_os = "freebsd",
                      target_os = "ios",
                      target_os = "macos",
                      target_os = "netbsd",
                      target_os = "openbsd"))]
            CIGNORE;
            CS5;
            CS6;
            CS7;
            CS8;
            CSTOPB;
            CREAD;
            PARENB;
            PARODD;
            HUPCL;
            CLOCAL;
            CRTSCTS;
            #[cfg(any(target_os = "android", target_os = "linux"))]
            CBAUD;
            #[cfg(any(target_os = "android", all(target_os = "linux", not(target_arch = "mips"))))]
            CMSPAR;
            #[cfg(any(target_os = "android",
                      all(target_os = "linux",
                          not(any(target_arch = "powerpc", target_arch = "powerpc64")))))]
            CIBAUD;
            #[cfg(any(target_os = "android", target_os = "linux"))]
            CBAUDEX;
            #[cfg(any(target_os = "dragonfly",
                      target_os = "freebsd",
                      target_os = "macos",
                      target_os = "netbsd",
                      target_os = "openbsd"))]
            MDMBUF;
            #[cfg(any(target_os = "netbsd", target_os = "openbsd"))]
            CHWFLOW;
            #[cfg(any(target_os = "dragonfly",
                      target_os = "freebsd",
                      target_os = "netbsd",
                      target_os = "openbsd"))]
            CCTS_OFLOW;
            #[cfg(any(target_os = "dragonfly",
                      target_os = "freebsd",
                      target_os = "netbsd",
                      target_os = "openbsd"))]
            CRTS_IFLOW;
            #[cfg(any(target_os = "dragonfly",
                      target_os = "freebsd"))]
            CDTR_IFLOW;
            #[cfg(any(target_os = "dragonfly",
                      target_os = "freebsd"))]
            CDSR_OFLOW;
            #[cfg(any(target_os = "dragonfly",
                      target_os = "freebsd"))]
            CCAR_OFLOW;

            // Bitmasks for use with ControlFlags to select specific settings
            // These should be moved to be a mask once https://github.com/rust-lang-nursery/bitflags/issues/110
            // is resolved.

            CSIZE;
        }
    }

    libc_bitflags! {
        /// Flags for setting any local modes
        pub struct LocalFlags: tcflag_t {
            ECHOKE;
            ECHOE;
            ECHOK;
            ECHO;
            ECHONL;
            ECHOPRT;
            ECHOCTL;
            ISIG;
            ICANON;
            #[cfg(any(target_os = "freebsd",
                      target_os = "dragonfly",
                      target_os = "ios",
                      target_os = "macos",
                      target_os = "netbsd",
                      target_os = "openbsd"))]
            ALTWERASE;
            IEXTEN;
            EXTPROC;
            TOSTOP;
            FLUSHO;
            #[cfg(any(target_os = "freebsd",
                      target_os = "dragonfly",
                      target_os = "ios",
                      target_os = "macos",
                      target_os = "netbsd",
                      target_os = "openbsd"))]
            NOKERNINFO;
            PENDIN;
            NOFLSH;
        }
    }

    cfg_if!{
        if #[cfg(any(target_os = "freebsd",
                     target_os = "dragonfly",
                     target_os = "ios",
                     target_os = "macos",
                     target_os = "netbsd",
                     target_os = "openbsd"))] {
            /// Get input baud rate (see
            /// [cfgetispeed(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/cfgetispeed.html)).
            ///
            /// `cfgetispeed()` extracts the input baud rate from the given `Termios` structure.
            pub fn cfgetispeed(termios: &Termios) -> u32 {
                let inner_termios = termios.get_libc_termios();
                unsafe { libc::cfgetispeed(&*inner_termios) as u32 }
            }

            /// Get output baud rate (see
            /// [cfgetospeed(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/cfgetospeed.html)).
            ///
            /// `cfgetospeed()` extracts the output baud rate from the given `Termios` structure.
            pub fn cfgetospeed(termios: &Termios) -> u32 {
                let inner_termios = termios.get_libc_termios();
                unsafe { libc::cfgetospeed(&*inner_termios) as u32 }
            }

            /// Set input baud rate (see
            /// [cfsetispeed(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/cfsetispeed.html)).
            ///
            /// `cfsetispeed()` sets the intput baud rate in the given `Termios` structure.
            pub fn cfsetispeed<T: Into<u32>>(termios: &mut Termios, baud: T) -> Result<()> {
                let inner_termios = unsafe { termios.get_libc_termios_mut() };
                let res = unsafe { libc::cfsetispeed(inner_termios, baud.into() as libc::speed_t) };
                termios.update_wrapper();
                Errno::result(res).map(drop)
            }

            /// Set output baud rate (see
            /// [cfsetospeed(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/cfsetospeed.html)).
            ///
            /// `cfsetospeed()` sets the output baud rate in the given termios structure.
            pub fn cfsetospeed<T: Into<u32>>(termios: &mut Termios, baud: T) -> Result<()> {
                let inner_termios = unsafe { termios.get_libc_termios_mut() };
                let res = unsafe { libc::cfsetospeed(inner_termios, baud.into() as libc::speed_t) };
                termios.update_wrapper();
                Errno::result(res).map(drop)
            }

            /// Set both the input and output baud rates (see
            /// [termios(3)](https://www.freebsd.org/cgi/man.cgi?query=cfsetspeed)).
            ///
            /// `cfsetspeed()` sets the input and output baud rate in the given termios structure. Note that
            /// this is part of the 4.4BSD standard and not part of POSIX.
            pub fn cfsetspeed<T: Into<u32>>(termios: &mut Termios, baud: T) -> Result<()> {
                let inner_termios = unsafe { termios.get_libc_termios_mut() };
                let res = unsafe { libc::cfsetspeed(inner_termios, baud.into() as libc::speed_t) };
                termios.update_wrapper();
                Errno::result(res).map(drop)
            }
        } else {
            /// Get input baud rate (see
            /// [cfgetispeed(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/cfgetispeed.html)).
            ///
            /// `cfgetispeed()` extracts the input baud rate from the given `Termios` structure.
            pub fn cfgetispeed(termios: &Termios) -> BaudRate {
                let inner_termios = termios.get_libc_termios();
                unsafe { libc::cfgetispeed(&*inner_termios) }.into()
            }

            /// Get output baud rate (see
            /// [cfgetospeed(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/cfgetospeed.html)).
            ///
            /// `cfgetospeed()` extracts the output baud rate from the given `Termios` structure.
            pub fn cfgetospeed(termios: &Termios) -> BaudRate {
                let inner_termios = termios.get_libc_termios();
                unsafe { libc::cfgetospeed(&*inner_termios) }.into()
            }

            /// Set input baud rate (see
            /// [cfsetispeed(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/cfsetispeed.html)).
            ///
            /// `cfsetispeed()` sets the intput baud rate in the given `Termios` structure.
            pub fn cfsetispeed(termios: &mut Termios, baud: BaudRate) -> Result<()> {
                let inner_termios = unsafe { termios.get_libc_termios_mut() };
                let res = unsafe { libc::cfsetispeed(inner_termios, baud as libc::speed_t) };
                termios.update_wrapper();
                Errno::result(res).map(drop)
            }

            /// Set output baud rate (see
            /// [cfsetospeed(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/cfsetospeed.html)).
            ///
            /// `cfsetospeed()` sets the output baud rate in the given `Termios` structure.
            pub fn cfsetospeed(termios: &mut Termios, baud: BaudRate) -> Result<()> {
                let inner_termios = unsafe { termios.get_libc_termios_mut() };
                let res = unsafe { libc::cfsetospeed(inner_termios, baud as libc::speed_t) };
                termios.update_wrapper();
                Errno::result(res).map(drop)
            }

            /// Set both the input and output baud rates (see
            /// [termios(3)](https://www.freebsd.org/cgi/man.cgi?query=cfsetspeed)).
            ///
            /// `cfsetspeed()` sets the input and output baud rate in the given `Termios` structure. Note that
            /// this is part of the 4.4BSD standard and not part of POSIX.
            pub fn cfsetspeed(termios: &mut Termios, baud: BaudRate) -> Result<()> {
                let inner_termios = unsafe { termios.get_libc_termios_mut() };
                let res = unsafe { libc::cfsetspeed(inner_termios, baud as libc::speed_t) };
                termios.update_wrapper();
                Errno::result(res).map(drop)
            }
        }
    }

    /// Configures the port to something like the "raw" mode of the old Version 7 terminal driver (see
    /// [termios(3)](http://man7.org/linux/man-pages/man3/termios.3.html)).
    ///
    /// `cfmakeraw()` configures the termios structure such that input is available character-by-
    /// character, echoing is disabled, and all special input and output processing is disabled. Note
    /// that this is a non-standard function, but is available on Linux and BSDs.
    pub fn cfmakeraw(termios: &mut Termios) {
        let inner_termios = unsafe { termios.get_libc_termios_mut() };
        unsafe {
            libc::cfmakeraw(inner_termios);
        }
        termios.update_wrapper();
    }

    /// Configures the port to "sane" mode (like the configuration of a newly created terminal) (see
    /// [tcsetattr(3)](https://www.freebsd.org/cgi/man.cgi?query=tcsetattr)).
    ///
    /// Note that this is a non-standard function, available on FreeBSD.
    #[cfg(target_os = "freebsd")]
    pub fn cfmakesane(termios: &mut Termios) {
        let inner_termios = unsafe { termios.get_libc_termios_mut() };
        unsafe {
            libc::cfmakesane(inner_termios);
        }
        termios.update_wrapper();
    }

    /// Return the configuration of a port
    /// [tcgetattr(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/tcgetattr.html)).
    ///
    /// `tcgetattr()` returns a `Termios` structure with the current configuration for a port. Modifying
    /// this structure *will not* reconfigure the port, instead the modifications should be done to
    /// the `Termios` structure and then the port should be reconfigured using `tcsetattr()`.
    pub fn tcgetattr(fd: RawFd) -> Result<Termios> {
        let mut termios: libc::termios = unsafe { mem::uninitialized() };

        let res = unsafe { libc::tcgetattr(fd, &mut termios) };

        Errno::result(res)?;

        Ok(termios.into())
    }

    /// Set the configuration for a terminal (see
    /// [tcsetattr(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/tcsetattr.html)).
    ///
    /// `tcsetattr()` reconfigures the given port based on a given `Termios` structure. This change
    /// takes affect at a time specified by `actions`. Note that this function may return success if
    /// *any* of the parameters were successfully set, not only if all were set successfully.
    pub fn tcsetattr(fd: RawFd, actions: SetArg, termios: &Termios) -> Result<()> {
        let inner_termios = termios.get_libc_termios();
        Errno::result(unsafe { libc::tcsetattr(fd, actions as c_int, &*inner_termios) }).map(drop)
    }

    /// Block until all output data is written (see
    /// [tcdrain(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/tcdrain.html)).
    pub fn tcdrain(fd: RawFd) -> Result<()> {
        Errno::result(unsafe { libc::tcdrain(fd) }).map(drop)
    }

    /// Suspend or resume the transmission or reception of data (see
    /// [tcflow(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/tcflow.html)).
    ///
    /// `tcflow()` suspends of resumes the transmission or reception of data for the given port
    /// depending on the value of `action`.
    pub fn tcflow(fd: RawFd, action: FlowArg) -> Result<()> {
        Errno::result(unsafe { libc::tcflow(fd, action as c_int) }).map(drop)
    }

    /// Discard data in the output or input queue (see
    /// [tcflush(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/tcflush.html)).
    ///
    /// `tcflush()` will discard data for a terminal port in the input queue, output queue, or both
    /// depending on the value of `action`.
    pub fn tcflush(fd: RawFd, action: FlushArg) -> Result<()> {
        Errno::result(unsafe { libc::tcflush(fd, action as c_int) }).map(drop)
    }

    /// Send a break for a specific duration (see
    /// [tcsendbreak(3p)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/tcsendbreak.html)).
    ///
    /// When using asynchronous data transmission `tcsendbreak()` will transmit a continuous stream
    /// of zero-valued bits for an implementation-defined duration.
    pub fn tcsendbreak(fd: RawFd, duration: c_int) -> Result<()> {
        Errno::result(unsafe { libc::tcsendbreak(fd, duration) }).map(drop)
    }

    /// Get the session controlled by the given terminal (see
    /// [tcgetsid(3)](http://pubs.opengroup.org/onlinepubs/9699919799/functions/tcgetsid.html)).
    pub fn tcgetsid(fd: RawFd) -> Result<Pid> {
        let res = unsafe { libc::tcgetsid(fd) };

        Errno::result(res).map(Pid::from_raw)
    }

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