1--- 2c: Copyright (C) Daniel Stenberg, <daniel.se>, et al. 3SPDX-License-Identifier: curl 4Title: curl_multi_socket 5Section: 3 6Source: libcurl 7See-also: 8 - curl_multi_cleanup (3) 9 - curl_multi_fdset (3) 10 - curl_multi_info_read (3) 11 - curl_multi_init (3) 12 - the hiperfifo.c example 13--- 14 15# NAME 16 17curl_multi_socket - reads/writes available data 18 19# SYNOPSIS 20 21~~~c 22#include <curl/curl.h> 23CURLMcode curl_multi_socket(CURLM *multi_handle, curl_socket_t sockfd, 24 int *running_handles); 25 26CURLMcode curl_multi_socket_all(CURLM *multi_handle, 27 int *running_handles); 28~~~ 29 30# DESCRIPTION 31 32These functions are deprecated. Do not use. See 33curl_multi_socket_action(3) instead. 34 35At return, the integer **running_handles** points to contains the number of 36still running easy handles within the multi handle. When this number reaches 37zero, all transfers are complete/done. Note that when you call 38curl_multi_socket_action(3) on a specific socket and the counter 39decreases by one, it DOES NOT necessarily mean that this exact socket/transfer 40is the one that completed. Use curl_multi_info_read(3) to figure out 41which easy handle that completed. 42 43The curl_multi_socket_action(3) functions inform the application about 44updates in the socket (file descriptor) status by doing none, one, or multiple 45calls to the socket callback function set with the 46CURLMOPT_SOCKETFUNCTION(3) option to curl_multi_setopt(3). They 47update the status with changes since the previous time the callback was 48called. 49 50Get the timeout time by setting the CURLMOPT_TIMERFUNCTION(3) option 51with curl_multi_setopt(3). Your application then gets called with 52information on how long to wait for socket actions at most before doing the 53timeout action: call the curl_multi_socket_action(3) function with the 54**sockfd** argument set to CURL_SOCKET_TIMEOUT. You can also use the 55curl_multi_timeout(3) function to poll the value at any given time, but 56for an event-based system using the callback is far better than relying on 57polling the timeout value. 58 59Usage of curl_multi_socket(3) is deprecated, whereas the function is 60equivalent to curl_multi_socket_action(3) with **ev_bitmask** set to 610. 62 63Force libcurl to (re-)check all its internal sockets and transfers instead of 64just a single one by calling curl_multi_socket_all(3). Note that there 65should not be any reason to use this function. 66 67# EXAMPLE 68 69~~~c 70int main(void) 71{ 72 /* the event-library gets told when there activity on the socket 'fd', 73 which we translate to a call to curl_multi_socket_action() */ 74 int running; 75 int rc; 76 int fd; 77 CURLM *multi; 78 rc = curl_multi_socket(multi, fd, &running); 79} 80~~~ 81 82# AVAILABILITY 83 84This function was added in libcurl 7.15.4, and is deemed stable since 857.16.0. 86 87curl_multi_socket(3) is deprecated, use 88curl_multi_socket_action(3) instead! 89 90# RETURN VALUE 91 92CURLMcode type, general libcurl multi interface error code. 93 94The return code is for the whole multi stack. Problems still might have 95occurred on individual transfers even when one of these functions return OK. 96