curl_multi_info_read(3)   libcurl Manual  curl_multi_info_read(3)



NAME
       curl_multi_info_read - read multi stack informationals

SYNOPSIS
       #include 

       CURLMsg *curl_multi_info_read( CURLM *multi_handle,
                                      int *msgs_in_queue);

DESCRIPTION
       Ask  the  multi  handle if there are any messages/informa-
       tionals  from  the  individual  transfers.  Messages   may
       include  informationals  such  as  an  error code from the
       transfer or just the fact that a  transfer  is  completed.
       More details on these should be written down as well.

       Repeated  calls  to this function will return a new struct
       each time, until a NULL is returned as a signal that there
       is  no  more  to get at this point. The integer pointed to
       with msgs_in_queue will contain the  number  of  remaining
       messages after this function was called.

       When  you  fetch  a  message  using  this  function, it is
       removed from the internal queue so calling  this  function
       again  will  not  return  the  same message again. It will
       instead return new messages at each new invoke  until  the
       queue is emptied.

       The  data  the returned pointer points to will not survive
       calling curl_multi_cleanup(3), curl_multi_remove_handle(3)
       or curl_easy_cleanup(3).

       The  'CURLMsg' struct is very simple and only contain very
       basic  information.   If  more  involved  information   is
       wanted,  the  particular  "easy handle" in present in that
       struct  and  can  thus  be  used  in  subsequent   regular
       curl_easy_getinfo(3) calls (or similar):

        struct CURLMsg {
          CURLMSG msg;       /* what this message means */
          CURL *easy_handle; /* the handle it concerns */
          union {
            void *whatever;    /* message-specific data */
            CURLcode result;   /* return code for transfer */
          } data;
        };

       When  msg is CURLMSG_DONE, the message identifies a trans-
       fer that is done, and then result contains the return code
       for the easy handle that just completed.

       At this point, there is no other msg types defined.

RETURN VALUE
       A  pointer  to a filled-in struct, or NULL if it failed or
       ran out of structs. It also writes the number of  messages
       left  in  the  queue  (after this read) in the integer the
       second argument points to.

SEE ALSO
       curl_multi_cleanup(3), curl_multi_init(3), curl_multi_per-
       form(3)