progress function example: include timed interval

Adds a timer based off of CURLINFO_TOTAL_TIME that is used to perform
certain actions after a minimum amount of time has passed using the
progress function. As a consequence the curl handle is now also passed
into the progress function. Progress example now also includes an
example of how to retreive the TOTAL_TIME and print it out.

diff --git a/docs/examples/progressfunc.c b/docs/examples/progressfunc.c
index 42ed328..a498060 100644 (file)
--- a/docs/examples/progressfunc.c
+++ b/docs/examples/progressfunc.c
@@ -22,12 +22,32 @@
 #include <stdio.h>
 #include <curl/curl.h>
 
-#define STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES 6000
+#define STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES         6000
+#define MINIMAL_PROGRESS_FUNCTIONALITY_INTERVAL     3
+
+struct myprogress {
+  double lastruntime;
+  CURL *curl;
+};
 
 static int progress(void *p,
                     double dltotal, double dlnow,
                     double ultotal, double ulnow)
 {
+  struct myprogress *myp = (struct myprogress *)p;
+  CURL *curl = myp->curl;
+  double curtime = 0;
+
+  curl_easy_getinfo(curl, CURLINFO_TOTAL_TIME, &curtime);
+
+  /* under certain circumstances it may be desirable for certain functionality
+     to only run every N seconds, in order to do this the transaction time can
+     be used */
+  if((curtime - myp->lastruntime) >= MINIMAL_PROGRESS_FUNCTIONALITY_INTERVAL) {
+    myp->lastruntime = curtime;
+    fprintf(stderr, "TOTAL TIME: %f \r\n", curtime);
+  }
+
   fprintf(stderr, "UP: %g of %g  DOWN: %g of %g\r\n",
           ulnow, ultotal, dlnow, dltotal);
 
@@ -40,11 +60,17 @@ int main(void)
 {
   CURL *curl;
   CURLcode res=0;
+  struct myprogress prog;
 
   curl = curl_easy_init();
   if(curl) {
+    prog.lastruntime = 0;
+    prog.curl = curl;
+
     curl_easy_setopt(curl, CURLOPT_URL, "http://example.com/");
     curl_easy_setopt(curl, CURLOPT_PROGRESSFUNCTION, progress);
+    /* pass the struct pointer into the progress function */
+    curl_easy_setopt(curl, CURLOPT_PROGRESSDATA, &prog);
     curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0L);
     res = curl_easy_perform(curl);