1/*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al. 9 * 10 * This software is licensed as described in the file COPYING, which 11 * you should have received as part of this distribution. The terms 12 * are also available at https://curl.haxx.se/docs/copyright.html. 13 * 14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell 15 * copies of the Software, and permit persons to whom the Software is 16 * furnished to do so, under the terms of the COPYING file. 17 * 18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 19 * KIND, either express or implied. 20 * 21 ***************************************************************************/ 22/* <DESC> 23 * using the multi interface to do a single download 24 * </DESC> 25 */ 26 27#include <stdio.h> 28#include <string.h> 29 30/* somewhat unix-specific */ 31#include <sys/time.h> 32#include <unistd.h> 33 34/* curl stuff */ 35#include <curl/curl.h> 36 37#ifdef _WIN32 38#define WAITMS(x) Sleep(x) 39#else 40/* Portable sleep for platforms other than Windows. */ 41#define WAITMS(x) \ 42 struct timeval wait = { 0, (x) * 1000 }; \ 43 (void)select(0, NULL, NULL, NULL, &wait); 44#endif 45 46/* 47 * Simply download a HTTP file. 48 */ 49int main(void) 50{ 51 CURL *http_handle; 52 CURLM *multi_handle; 53 54 int still_running; /* keep number of running handles */ 55 int repeats = 0; 56 57 curl_global_init(CURL_GLOBAL_DEFAULT); 58 59 http_handle = curl_easy_init(); 60 61 /* set the options (I left out a few, you'll get the point anyway) */ 62 curl_easy_setopt(http_handle, CURLOPT_URL, "http://www.example.com/"); 63 64 /* init a multi stack */ 65 multi_handle = curl_multi_init(); 66 67 /* add the individual transfers */ 68 curl_multi_add_handle(multi_handle, http_handle); 69 70 /* we start some action by calling perform right away */ 71 curl_multi_perform(multi_handle, &still_running); 72 73 do { 74 CURLMcode mc; /* curl_multi_wait() return code */ 75 int numfds; 76 77 /* wait for activity, timeout or "nothing" */ 78 mc = curl_multi_wait(multi_handle, NULL, 0, 1000, &numfds); 79 80 if(mc != CURLM_OK) { 81 fprintf(stderr, "curl_multi_wait() failed, code %d.\n", mc); 82 break; 83 } 84 85 /* 'numfds' being zero means either a timeout or no file descriptors to 86 wait for. Try timeout on first occurrence, then assume no file 87 descriptors and no file descriptors to wait for means wait for 100 88 milliseconds. */ 89 90 if(!numfds) { 91 repeats++; /* count number of repeated zero numfds */ 92 if(repeats > 1) { 93 WAITMS(100); /* sleep 100 milliseconds */ 94 } 95 } 96 else 97 repeats = 0; 98 99 curl_multi_perform(multi_handle, &still_running); 100 } while(still_running); 101 102 curl_multi_remove_handle(multi_handle, http_handle); 103 104 curl_easy_cleanup(http_handle); 105 106 curl_multi_cleanup(multi_handle); 107 108 curl_global_cleanup(); 109 110 return 0; 111} 112