Function select

crates/stdlib/src/select.rs:174–199

(
    nfds: libc::c_int,
    readfds: &mut FdSet,
    writefds: &mut FdSet,
    errfds: &mut FdSet,
    timeout: Option<&mut timeval>,
)

}

pub fn select(
    nfds: libc::c_int,
    readfds: &mut FdSet,
    writefds: &mut FdSet,
    errfds: &mut FdSet,
    timeout: Option<&mut timeval>,
) -> io::Result<i32> {
    let timeout = match timeout {
        Some(tv) => tv as *mut timeval,
        None => core::ptr::null_mut(),
    };
    let ret = unsafe {
        platform::select(
            nfds,
            readfds.0.as_mut_ptr(),
            writefds.0.as_mut_ptr(),
            errfds.0.as_mut_ptr(),
            timeout,
        )
    };
    if platform::check_err(ret) {
        Err(io::Error::last_os_error())
    } else {
        Ok(ret)
    }
}

fn sec_to_timeval(sec: f64) -> timeval {
    timeval {