- To make it easier for applications that want lots of magic stuff done on

redirections and thus cannot use CURLOPT_FOLLOWLOCATION easily, we now
  introduce the new CURLINFO_REDIRECT_URL option that lets applications
  extract the URL libcurl would've redirected to if it had been told to. This
  then enables the application to continue to that URL as it thinks is
  suitable, without having to re-implement the magic of creating the new URL
  from the Location: header etc. Test 1029 verifies it.

src/writeout.c

@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2006, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2008, 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
@@ -61,6 +61,7 @@ typedef enum {
   VAR_REDIRECT_TIME,
   VAR_REDIRECT_COUNT,
   VAR_FTP_ENTRY_PATH,
+  VAR_REDIRECT_URL,
   VAR_NUM_OF_VARS /* must be the last */
 } replaceid;
 
@@ -73,6 +74,7 @@ struct variable {
 static const struct variable replacements[]={
   {"url_effective", VAR_EFFECTIVE_URL},
   {"http_code", VAR_HTTP_CODE},
+  {"response_code", VAR_HTTP_CODE},
   {"http_connect", VAR_HTTP_CODE_PROXY},
   {"time_total", VAR_TOTAL_TIME},
   {"time_namelookup", VAR_NAMELOOKUP_TIME},
@@ -90,6 +92,7 @@ static const struct variable replacements[]={
   {"time_redirect", VAR_REDIRECT_TIME},
   {"num_redirects", VAR_REDIRECT_COUNT},
   {"ftp_entry_path", VAR_FTP_ENTRY_PATH},
+  {"redirect_url", VAR_REDIRECT_URL},
   {NULL, VAR_NONE}
 };
 
@@ -222,6 +225,12 @@ void ourWriteOut(CURL *curl, const char *writeinfo)
                    && stringp)
                   fputs(stringp, stream);
                 break;
+              case VAR_REDIRECT_URL:
+                if((CURLE_OK ==
+                    curl_easy_getinfo(curl, CURLINFO_REDIRECT_URL, &stringp))
+                   && stringp)
+                  fputs(stringp, stream);
+                break;
               default:
                 break;
               }