library/std/src/sys/anonymous_pipe/mod.rs

#![forbid(unsafe_op_in_unsafe_fn)]

cfg_if::cfg_if! {
    if #[cfg(unix)] {
        mod unix;
        pub use unix::{AnonPipe, pipe};
    } else if #[cfg(windows)] {
        mod windows;
        pub use windows::{AnonPipe, pipe};
    } else {
        mod unsupported;
        pub use unsupported::{AnonPipe, pipe};
    }
}