curl/docs/examples/multi-single.c

95 lines
2.4 KiB
C

/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* $Id$
*
* 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 a HTTP file.
*/
int main(int argc, char **argv)
{
CURL *http_handle;
CURLM *multi_handle;
int still_running; /* keep number of running handles */
http_handle = curl_easy_init();
/* set the options (I left out a few, you'll get the point anyway) */
curl_easy_setopt(http_handle, CURLOPT_URL, "http://www.haxx.se/");
/* init a multi stack */
multi_handle = curl_multi_init();
/* add the individual transfers */
curl_multi_add_handle(multi_handle, http_handle);
/* we start some action by calling perform right away */
while(CURLM_CALL_MULTI_PERFORM ==
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;
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;
/* 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, *and* you make sure that maxfd is bigger than -1 so
that the call to select() below makes sense! */
rc = select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout);
switch(rc) {
case -1:
/* select error */
still_running = 0;
printf("select() returns error, this is badness\n");
break;
case 0:
default:
/* timeout or readable/writable sockets */
while(CURLM_CALL_MULTI_PERFORM ==
curl_multi_perform(multi_handle, &still_running));
break;
}
}
curl_multi_cleanup(multi_handle);
curl_easy_cleanup(http_handle);
return 0;
}