curl_multi_info_read(3) libcurl Manual curl_multi_info_read(3)
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 contain very basic information. If more involved infor-mation information
mation is wanted, the particular "easy handle" in present in that struct and can thus be used in sub-sequent subsequent
sequent 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 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 num-ber number
ber 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)
libcurl 7.10.3 18 Dec 2004 curl_multi_info_read(3)
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