For https://github.com/saghul/pycares/issues/10

getaddrinfo.py

import select
import socket
import pycares


class CAresError(socket.error):
    def __init__(self, errno, strerror):
        super(CAresError, self).__init__(errno, strerror)


def wait(channel):
    while True:
        read_fds, write_fds = channel.getsock()
        if not read_fds and not write_fds:
            break
        timeout = channel.timeout()
        if timeout == 0.0:
            channel.process_fd(pycares.ARES_SOCKET_BAD, pycares.ARES_SOCKET_BAD)
            continue
        rlist, wlist, _ = select.select(read_fds, write_fds, [], timeout)
        for fd in rlist:
            channel.process_fd(fd, pycares.ARES_SOCKET_BAD)
        for fd in wlist:
            channel.process_fd(pycares.ARES_SOCKET_BAD, fd)


def getaddrinfo(host, port, channel=None, timeout=1.0):
    timeout = float(timeout)

    errors = []
    def callback4(res, errno):
        if errno:
            errors.append(CAresError(errno, pycares.errno.strerror(errno)))
        else:
            callback4.res = [(socket.AF_INET, socket.SOCK_STREAM, socket.IPPROTO_TCP, '', (addr, port))
                             for addr in res.addresses]
    callback4.res = None

    def callback6(res, errno):
        if errno:
            errors.append(CAresError(errno, pycares.errno.strerror(errno)))
        else:
            callback6.res = [(socket.AF_INET6, socket.SOCK_STREAM, socket.IPPROTO_TCP, '', (addr, port, 0, 0))
                             for addr in res.addresses]
    callback6.res = None

    if channel is None:
        channel = pycares.Channel(timeout=timeout)
    channel.gethostbyname(host, socket.AF_INET6, callback6)
    channel.gethostbyname(host, socket.AF_INET, callback4)
    wait(channel)
    if len(errors) > 0:
        raise errors[0]
    return callback6.res + callback4.res

from pprint import pprint as pp
# This should work
pp(getaddrinfo('google.com', 80, timeout=1.00))
# This does not work
pp(getaddrinfo('google.com', 80, timeout=0.99))