#include <curl/curl.h> CURLMcode curl_multi_socket(CURLM * multi_handle, curl_socket_t sockfd, int *running_handles); CURLMcode curl_multi_socket_all(CURLM *multi_handle, int *running_handles);
|multi_handle||Pointer to a multi handle.|
|running_handles||Pointer to running handles.|
If the operation was successful,
CURLM_OK is returned. Otherwise, a specific
CURLM libcurl Error Code is returned.
This is a legacy function. If
CURLM_CALL_MULTI_PERFORM is received, it is an indication to call
curl_multi_socket again, before you wait for more actions on libcurl's sockets.
Though not an immediate requirement, the return code indicates that libcurl may have more data available to return or that there may be more data to send off before it is "satisfied".
In modern libcurls,
CURLM_CALL_MULTI_SOKCET should not be returned and no application needs to be concerned about them.
The return code is for the whole multi stack. Issues still might have occurred on individual transfers even when one of these functions return as expected.
These functions are deprecated. Do not use. For information on an alternative, see
At return, the integer running_handles points to will contain the number of still running easy handles within the multi handle.
When this number reaches zero, all transfers are complete/done. Note that when you call
curl_multi_socket_action on a specific socket and the counter
decreases by one, it does not necessarily infer that this exact socket/transfer is the one that completed. Use
curl_multi_info_read to determine which easy handle that completed.
curl_multi_socket_action functions inform the application about updates in the socket (file descriptor) status by doing none, one, or
multiple calls to the socket callback function set with the
CURLMOPT_SOCKETFUNCTION option to
curl_multi_setopt. They update the status with changes since the previous time the callback was called.
Get the timeout time by setting the
CURLMOPT_TIMERFUNCTION option with
curl_multi_setopt. Your application will then get called with
information on how long to wait for socket actions at most before doing the timeout action: call the
curl_multi_socket_action function with the
sockfd argument set to
CURL_SOCKET_TIMEOUT. You can also use the
curl_multi_timeout function to poll the value at any given time, but for an event-based system using the callback is far better than relying on polling the timeout value.
curl_multi_socket is deprecated, whereas the function is equivalent to
ev_bitmask set to
Force libcurl to (re-)check all its internal sockets and transfers instead of a single one by calling
The socket callback function uses a prototype similar to the following.
int curl_socket_callback(CURL *easy, /* easy handle */ curl_socket_t s, /* socket */ int action, /* see values below */ void *userp, /* private callback pointer */ void *socketp); /* private socket pointer */
The callback must return
The easy argument is a pointer to the easy handle that deals with this particular socket. Note that a single handle may work with several sockets simultaneously.
The s argument is the actual socket value as you use it within your system.
The action argument to the callback has one of five values:
Register, not interested in readiness (yet).
Register, interested in read readiness.
Register, interested in write readiness.
Register, interested in both read and write readiness.
The socketp argument is a private pointer you have previously set with
curl_multi_assign to be associated with the
s socket. If no pointer has been set, socketp will be
NULL. This argument is a service to applications that want to keep certain data or
structs that are strictly associated to the given socket.
The userp argument is a private pointer you have previously set with
CURLMOPT_TIMERFUNCTION, to discover what timeout value to use when waiting for socket activities.
curl_multi_socket_actionfor the socket(s) that had action. If no activity is detected and the timeout expires, call
This function was added in libcurl 7.15.4, and is deemed stable since 7.16.0.
curl_multi_socket is deprecated, use
|Deprecated||Do not call this function in new code.|
2013/11/27 Worked broken link.
2013/05/08 Automated cleanup pass.
2012/05/04 Initial version.