progressfunc: a simple CURLOPT_PROGRESSFUNCTION example

docs/examples/.gitignore

@@ -26,6 +26,7 @@ multi-single
 persistant
 post-callback
 postit2
+progressfunc
 resolve
 rtsp
 sendrecv

docs/examples/Makefile.inc

@@ -4,7 +4,8 @@ check_PROGRAMS = 10-at-a-time anyauthput cookie_interface debug fileupload \
   https multi-app multi-debugcallback multi-double multi-post multi-single \
   persistant post-callback postit2 sepheaders simple simplepost simplessl  \
   sendrecv httpcustomheader certinfo chkspeed ftpgetinfo ftp-wildcard \
-  smtp-multi simplesmtp smtp-tls rtsp externalsocket resolve
+  smtp-multi simplesmtp smtp-tls rtsp externalsocket resolve \
+  progressfunc
 
 # These examples require external dependencies that may not be commonly
 # available on POSIX systems, so don't bother attempting to compile them here.

docs/examples/progressfunc.c

+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2011, 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 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.
+ *
+ ***************************************************************************/
+#include <stdio.h>
+#include <curl/curl.h>
+
+#define STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES 6000
+
+static int progress(void *p,
+                    double dltotal, double dlnow,
+                    double ultotal, double ulnow)
+{
+  fprintf(stderr, "UP: %g of %g  DOWN: %g of %g\r\n",
+          ulnow, ultotal, dlnow, dltotal);
+
+  if(dlnow > STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES)
+    return 1;
+  return 0;
+}
+
+int main(void)
+{
+  CURL *curl;
+  CURLcode res=0;
+
+  curl = curl_easy_init();
+  if(curl) {
+    curl_easy_setopt(curl, CURLOPT_URL, "http://example.com/");
+    curl_easy_setopt(curl, CURLOPT_PROGRESSFUNCTION, progress);
+    curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0L);
+    res = curl_easy_perform(curl);
+
+    if(res)
+      fprintf(stderr, "%s\n", curl_easy_strerror(res));
+
+    /* always cleanup */
+    curl_easy_cleanup(curl);
+  }
+  return (int)res;
+}