diff options
Diffstat (limited to 'docs/examples/multi-single.c')
-rw-r--r-- | docs/examples/multi-single.c | 103 |
1 files changed, 54 insertions, 49 deletions
diff --git a/docs/examples/multi-single.c b/docs/examples/multi-single.c index f248afe7..a43a9f52 100644 --- a/docs/examples/multi-single.c +++ b/docs/examples/multi-single.c @@ -1,13 +1,25 @@ -/***************************************************************************** +/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * + * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al. * - * This is a very simple example using the multi interface. - */ + * 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 http://curl.haxx.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. + * + ***************************************************************************/ +/* This is a very simple example using the multi interface. */ #include <stdio.h> #include <string.h> @@ -19,15 +31,27 @@ /* 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(int argc, char **argv) +int main(void) { CURL *http_handle; CURLM *multi_handle; int still_running; /* keep number of running handles */ + int repeats = 0; + + curl_global_init(CURL_GLOBAL_DEFAULT); http_handle = curl_easy_init(); @@ -43,62 +67,43 @@ int main(int argc, char **argv) /* 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 */ + do { + CURLMcode mc; /* curl_multi_wait() return code */ + int numfds; - fd_set fdread; - fd_set fdwrite; - fd_set fdexcep; - int maxfd = -1; + /* wait for activity, timeout or "nothing" */ + mc = curl_multi_wait(multi_handle, NULL, 0, 1000, &numfds); - long curl_timeo = -1; - - FD_ZERO(&fdread); - FD_ZERO(&fdwrite); - FD_ZERO(&fdexcep); + if(mc != CURLM_OK) + { + fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc); + break; + } - /* set a suitable timeout to play around with */ - timeout.tv_sec = 1; - timeout.tv_usec = 0; + /* '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. */ - 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; + if(!numfds) { + repeats++; /* count number of repeated zero numfds */ + if(repeats > 1) { + WAITMS(100); /* sleep 100 milliseconds */ + } } + else + repeats = 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. 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. */ + curl_multi_perform(multi_handle, &still_running); + } while(still_running); - rc = select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout); + curl_multi_remove_handle(multi_handle, http_handle); - 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 */ - curl_multi_perform(multi_handle, &still_running); - break; - } - } + curl_easy_cleanup(http_handle); curl_multi_cleanup(multi_handle); - curl_easy_cleanup(http_handle); + curl_global_cleanup(); return 0; } |