1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
|
/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
*
* This is a very simple example using the multi interface.
*/
#include <stdio.h>
#include <string.h>
/* somewhat unix-specific */
#include <sys/time.h>
#include <unistd.h>
/* curl stuff */
#include <curl/curl.h>
/*
* Simply download two HTTP files!
*/
int main(int argc, char **argv)
{
CURL *http_handle;
CURL *http_handle2;
CURLM *multi_handle;
int still_running; /* keep number of running handles */
http_handle = curl_easy_init();
http_handle2 = curl_easy_init();
/* set options */
curl_easy_setopt(http_handle, CURLOPT_URL, "http://www.example.com/");
/* set options */
curl_easy_setopt(http_handle2, CURLOPT_URL, "http://localhost/");
/* init a multi stack */
multi_handle = curl_multi_init();
/* add the individual transfers */
curl_multi_add_handle(multi_handle, http_handle);
curl_multi_add_handle(multi_handle, http_handle2);
/* we start some action by calling perform right away */
curl_multi_perform(multi_handle, &still_running);
while(still_running) {
struct timeval timeout;
int rc; /* select() return code */
fd_set fdread;
fd_set fdwrite;
fd_set fdexcep;
int maxfd = -1;
long curl_timeo = -1;
FD_ZERO(&fdread);
FD_ZERO(&fdwrite);
FD_ZERO(&fdexcep);
/* set a suitable timeout to play around with */
timeout.tv_sec = 1;
timeout.tv_usec = 0;
curl_multi_timeout(multi_handle, &curl_timeo);
if(curl_timeo >= 0) {
timeout.tv_sec = curl_timeo / 1000;
if(timeout.tv_sec > 1)
timeout.tv_sec = 1;
else
timeout.tv_usec = (curl_timeo % 1000) * 1000;
}
/* get file descriptors from the transfers */
curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);
/* In a real-world program you OF COURSE check the return code of the
function calls. On success, the value of maxfd is guaranteed to be
greater or equal than -1. We call select(maxfd + 1, ...), specially in
case of (maxfd == -1), we call select(0, ...), which is basically equal
to sleep. */
rc = select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout);
switch(rc) {
case -1:
/* select error */
break;
case 0:
default:
/* timeout or readable/writable sockets */
curl_multi_perform(multi_handle, &still_running);
break;
}
}
curl_multi_cleanup(multi_handle);
curl_easy_cleanup(http_handle);
curl_easy_cleanup(http_handle2);
return 0;
}
|
