# CurlMulti Object

class pycurl.CurlMulti

  Creates a new CurlMulti Object which corresponds to a `CURLM` handle in libcurl.

  CurlMulti objects have the following methods:

  close() → None

    Corresponds to curl_multi_cleanup in libcurl. This method is automatically called by pycurl when a CurlMulti object no longer has any references to it, but can also be called explicitly.

  add_handle(Curl object) → None

    Corresponds to curl_multi_add_handle in libcurl. This method adds an existing and valid Curl object to the CurlMulti object.

    Changed in version 7.43.0.2: add_handle now ensures that the Curl object is not garbage collected while it is being used by a CurlMulti object. Previously application had to maintain an outstanding reference to the Curl object to keep it from being garbage collected.

  remove_handle(Curl object) → None

    Corresponds to curl_multi_remove_handle in libcurl. This method removes an existing and valid Curl object from the CurlMulti object.

  perform() → tuple of status and the number of active Curl objects

    Corresponds to curl_multi_perform in libcurl.

  socket_action(sock_fd, ev_bitmask)

    Returns result from doing a socket_action() on the curl multi file descriptor with the given timeout. Corresponds to curl_multi_socket_action in libcurl.

    The return value is a two-element tuple. The first element is the return value of the underlying `curl_multi_socket_action` function, and it is always zero (`CURLE_OK`) because any other return value would cause `socket_action` to raise an exception. The second element is the number of running easy handles within this multi handle. When the number of running handles reaches zero, all transfers have completed. Note that if the number of running handles has decreased by one compared to the previous invocation, this is not mean the handle corresponding to the `sock_fd` provided as the argument to this function was the completed handle.

  socket_all() → tuple

    Returns result from doing a socket_all() on the curl multi file descriptor with the given timeout.

  setopt(option, value) → None

    Set curl multi option. Corresponds to curl_multi_setopt in libcurl.

    option specifies which option to set. PycURL defines constants corresponding to `CURLMOPT_*` constants in libcurl, except that the `CURLMOPT_` prefix is replaced with `M_` prefix. For example, `CURLMOPT_PIPELINING` is exposed in PycURL as `pycurl.M_PIPELINING`. For convenience, `CURLMOPT_*` constants are also exposed on CurlMulti objects:

        import pycurl
        m = pycurl.CurlMulti()
        m.setopt(pycurl.M_PIPELINING, 1)
        # Same as:
        m.setopt(m.M_PIPELINING, 1)

    value specifies the value to set the option to. Different options accept values of different types:

    - Options specified by curl_multi_setopt as accepting `1` or an integer value accept Python integers, long integers (on Python 2.x) and booleans:

          m.setopt(pycurl.M_PIPELINING, True)
          m.setopt(pycurl.M_PIPELINING, 1)
          # Python 2.x only:
          m.setopt(pycurl.M_PIPELINING, 1L)

    - `*FUNCTION` options accept a function. Supported callbacks are `CURLMOPT_SOCKETFUNCTION` AND `CURLMOPT_TIMERFUNCTION`. Please refer to the PycURL test suite for examples on using the callbacks.

    Raises TypeError when the option value is not of a type accepted by the respective option, and pycurl.error exception when libcurl rejects the option or its value.

  fdset() → tuple of lists with active file descriptors, readable, writeable, exceptions

    Returns a tuple of three lists that can be passed to the select.select() method.

    Corresponds to curl_multi_fdset in libcurl. This method extracts the file descriptor information from a CurlMulti object. The returned lists can be used with the `select` module to poll for events.

    Example usage:

        import pycurl
        c = pycurl.Curl()
        c.setopt(pycurl.URL, "https://curl.haxx.se")
        m = pycurl.CurlMulti()
        m.add_handle(c)
        while 1:
            ret, num_handles = m.perform()
            if ret != pycurl.E_CALL_MULTI_PERFORM: break
        while num_handles:
            apply(select.select, m.fdset() + (1,))
            while 1:
                ret, num_handles = m.perform()
                if ret != pycurl.E_CALL_MULTI_PERFORM: break

  select([timeout]) → number of ready file descriptors or 0 on timeout

    Returns result from doing a select() on the curl multi file descriptor with the given timeout.

    This is a convenience function which simplifies the combined use of `fdset()` and the `select` module.

    Example usage:

        import pycurl
        c = pycurl.Curl()
        c.setopt(pycurl.URL, "https://curl.haxx.se")
        m = pycurl.CurlMulti()
        m.add_handle(c)
        while 1:
            ret, num_handles = m.perform()
            if ret != pycurl.E_CALL_MULTI_PERFORM: break
        while num_handles:
            ret = m.select(1.0)
            if ret == 0:  continue
            while 1:
                ret, num_handles = m.perform()
                if ret != pycurl.E_CALL_MULTI_PERFORM: break

  info_read([max_objects]) -> tuple(number of queued messages, a list of successful objects, a list of failed objects)

    Corresponds to the curl_multi_info_read function in libcurl.

    This method extracts at most max messages from the multi stack and returns them in two lists. The first list contains the handles which completed successfully and the second list contains a tuple (curl object, curl error number, curl error message) for each failed curl object. The curl error message is returned as a Python string which is decoded from the curl error string using the surrogateescape error handler. The number of queued messages after this method has been called is also returned.

  timeout() → int

    Returns how long to wait for action before proceeding. Corresponds to curl_multi_timeout in libcurl.

  assign(sock_fd, object) → None

    Creates an association in the multi handle between the given socket and a private object in the application. Corresponds to curl_multi_assign in libcurl.