- CURLOPT_FTP_CREATE_MISSING_DIRS can now be set to 2 in addition to 1 for

plain FTP connections, and it will then allow MKD to fail once and retry the
  CWD afterwards. This is especially useful if you're doing many simultanoes
  connections against the same server and they all have this option enabled,
  as then CWD may first fail but then another connection does MKD before this
  connection and thus MKD fails but trying CWD works! The numbers can
  (should?) now be set with the convenience enums now called
  CURLFTP_CREATE_DIR and CURLFTP_CREATE_DIR_RETRY.

  Tests has proven that if you're making an application that uploads a set of
  files to an ftp server, you will get a noticable gain in speed if you're
  using multiple connections and this option will be then be very useful.

lib/urldata.h

@@ -1474,6 +1474,10 @@ struct UserDefined {
 
   curl_ftpfile ftp_filemethod; /* how to get to a file when FTP is used  */
 
+  int ftp_create_missing_dirs; /* 1 - create directories that don't exist
+                                  2 - the same but also allow MKD to fail once
+                               */
+
 /* Here follows boolean settings that define how to behave during
    this session. They are STATIC, set by libcurl users or at least initially
    and they don't change during operations. */
@@ -1484,7 +1488,6 @@ struct UserDefined {
   bool prefer_ascii;     /* ASCII rather than binary */
   bool ftp_append;       /* append, not overwrite, on upload */
   bool ftp_list_only;    /* switch FTP command for listing directories */
-  bool ftp_create_missing_dirs; /* create directories that don't exist */
   bool ftp_use_port;     /* use the FTP PORT command */
   bool hide_progress;    /* don't use the progress meter */
   bool http_fail_on_error;  /* fail on HTTP error codes >= 300 */