Dave Dribin made it possible to set CURLOPT_COOKIEFILE to "" to activate

the cookie "engine" without having to provide an empty or non-existing file.

CHANGES

@@ -8,6 +8,9 @@
 
 
 Daniel (4 March 2005)
+- Dave Dribin made it possible to set CURLOPT_COOKIEFILE to "" to activate
+  the cookie "engine" without having to provide an empty or non-existing file.
+
 - Rene Rebe fixed a -# crash when more data than expected was retrieved.
 
 Daniel (22 February 2005)

RELEASE-NOTES

@@ -10,6 +10,7 @@ Curl and libcurl 7.13.1
 
 This release includes the following changes:
 
+ o CURLOPT_COOKIEFILE set to "" is now activating the cookie engine
  o FTP code overhaul => multi interface much less blocking
  o Added CURLE_LOGIN_DENIED to be returned when curl is denied login to FTP
    servers
@@ -39,6 +40,6 @@ advice from friends like these:
 
  Gisle Vanem, David Byron, Marty Kuhrt, Maruko, Eric Vergnaud, Christopher
  R. Palmer, Mike Dobbs, David in bug report #1124588, Ralph Mitchell,
- Rene Rebe
+ Rene Rebe, Dave Dribin
 
         Thanks! (and sorry if I forgot to mention someone)

docs/libcurl/curl_easy_setopt.3

@@ -617,9 +617,9 @@ name of your file holding cookie data to read. The cookie data may be in
 Netscape / Mozilla cookie data format or just regular HTTP-style headers
 dumped to a file.
 
-Given an empty or non-existing file, this option will enable cookies for this
-curl handle, making it understand and parse received cookies and then use
-matching cookies in future request.
+Given an empty or non-existing file or by passing the empty string (""), this
+option will enable cookies for this curl handle, making it understand and
+parse received cookies and then use matching cookies in future request.
 .IP CURLOPT_COOKIEJAR
 Pass a file name as char *, zero terminated. This will make libcurl write all
 internally known cookies to the specified file when \fIcurl_easy_cleanup(3)\fP

lib/cookie.c

@@ -651,6 +651,10 @@ struct CookieInfo *Curl_cookie_init(struct SessionHandle *data,
     fp = stdin;
     fromfile=FALSE;
   }
+  else if(file && !*file) {
+    /* points to a "" string */
+    fp = NULL;
+  }
   else
     fp = file?fopen(file, "r"):NULL;