/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at https://curl.se/docs/copyright.html. * * You may opt to use, copy, modify, merge, publish, distribute and/or sell * copies of the Software, and permit persons to whom the Software is * furnished to do so, under the terms of the COPYING file. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ***************************************************************************/ /* <DESC> * using the multi interface to do a single download * </DESC> */ #include <stdio.h> #include <string.h> /* somewhat unix-specific */ #include <sys/time.h> #include <unistd.h> /* curl stuff */ #include <curl/curl.h> #ifdef _WIN32 #define WAITMS(x) Sleep(x) #else /* Portable sleep for platforms other than Windows. */ #define WAITMS(x) \ struct timeval wait = { 0, (x) * 1000 }; \ (void)select(0, NULL, NULL, NULL, &wait) #endif /* * Simply download a HTTP file. */ int main(void) { CURL *http_handle; CURLM *multi_handle; int still_running = 0; /* keep number of running handles */ int repeats = 0; curl_global_init(CURL_GLOBAL_DEFAULT); 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, "https://www.example.com/"); /* 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 */ curl_multi_perform(multi_handle, &still_running); while(still_running) { CURLMcode mc; /* curl_multi_wait() return code */ int numfds; /* wait for activity, timeout or "nothing" */ mc = curl_multi_wait(multi_handle, NULL, 0, 1000, &numfds); if(mc != CURLM_OK) { fprintf(stderr, "curl_multi_wait() failed, code %d.\n", mc); break; } /* 'numfds' being zero means either a timeout or no file descriptors to wait for. Try timeout on first occurrence, then assume no file descriptors and no file descriptors to wait for means wait for 100 milliseconds. */ if(!numfds) { repeats++; /* count number of repeated zero numfds */ if(repeats > 1) { WAITMS(100); /* sleep 100 milliseconds */ } } else repeats = 0; curl_multi_perform(multi_handle, &still_running); } curl_multi_remove_handle(multi_handle, http_handle); curl_easy_cleanup(http_handle); curl_multi_cleanup(multi_handle); curl_global_cleanup(); return 0; }