NAME

       curl_multi_info_read - read multi stack informationals

SYNOPSIS

       #include <curl/curl.h>

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

DESCRIPTION

       Ask the multi handle if there are any messages/informationals 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.

       WARNING:  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  contains  very  basic  information.   If  more  involved
       information  is  wanted,  the  particular  "easy  handle"  is  present  in that struct and can 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 transfer that is done, and then  result  contains  the
       return code for the easy handle that just completed.

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

EXAMPLE

       struct CURLMsg *m;

       /* call curl_multi_perform or curl_multi_socket_action first, then loop
          through and check if there are any transfers that have completed */

       do {
         int msgq = 0;
         m = curl_multi_info_read(multi_handle, &msgq);
         if(m && (m->msg == CURLMSG_DONE)) {
           CURL *e = m->easy_handle;
           transfers--;
           curl_multi_remove_handle(multi_handle, e);
           curl_easy_cleanup(e);
         }
       } while(m);

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_perform(3)