#[cfg(windows)]
pub fn descendents_of(parent_pid: pid_t) -> Result<Vec<pid_t>, Error> {
    use std::os::windows::io::RawHandle;
    use winapi::um::processthreadsapi::{GetProcessId, OpenProcess};
    use winapi::um::winnt::{ACCESS_MASK, MAXIMUM_ALLOWED, HANDLE, PROCESS_QUERY_INFORMATION};
    use winapi::um::handleapi::CloseHandle;
    use winapi::shared::minwindef::{FALSE, ULONG};
    use winapi::shared::ntdef::NTSTATUS;

    #[link(name="ntdll")]
    extern "system" {
        // (Vista and above) enumerate process children.
        fn NtGetNextProcess(process: HANDLE, access: ACCESS_MASK, attritubes: ULONG, flags: ULONG, new_process: *mut HANDLE) -> NTSTATUS;
    }

    let mut handle = unsafe {
        OpenProcess(PROCESS_QUERY_INFORMATION, FALSE, parent_pid)
    };

    let mut handles = vec![handle];

    if handle == (0 as RawHandle) {
        return Err(format_err!(
            "Unable to fetch process handle for process {}", parent_pid
        ));
    }

    unsafe {
        while NtGetNextProcess(handle, MAXIMUM_ALLOWED, 0, 0,
                               &mut handle) == 0 {
            handles.push(handle);
        }
    }

    let ret = handles.iter().map(|x| {
        let pid = GetProcessId(x);

        unsafe { CloseHandle(x) };

        pid
    }).collect();

    println!("TODO: debugging, remove!!! {:?}", ret);

    Ok(ret)
}