Function set_controlling_tty

crates/openshell-supervisor-process/src/ssh.rs:1088–1094

(fd: RawFd)

    // cross-platform conversion so the same expression compiles everywhere.
    #[allow(clippy::useless_conversion)]
    fn set_controlling_tty(fd: RawFd) -> std::io::Result<()> {
        let rc = unsafe { libc::ioctl(fd, libc::TIOCSCTTY.into(), 0) };
        if rc != 0 {
            return Err(std::io::Error::last_os_error());
        }
        Ok(())
    }

    #[allow(unsafe_code)]
    #[cfg_attr(