- 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.

docs/libcurl/curl_easy_setopt.3

@@ -1103,6 +1103,17 @@ This setting also applies to SFTP-connections. curl will attempt to create
 the remote directory if it can't obtain a handle to the target-location. The
 creation will fail if a file of the same name as the directory to create
 already exists or lack of permissions prevents creation. (Added in 7.16.3)
+
+Starting with 7.19.4, you can also set this value to 2, which will make
+libcurl retry the CWD command again if the subsequent MKD command fails. 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! 7.19.4 also introduced the \fICURLFTP_CREATE_DIR\fP and
+\fICURLFTP_CREATE_DIR_RETRY\fP enum names for these arguments.
+
+Before version 7.19.4, libcurl will simply ignore arguments set to 2 and act
+as if 1 was selected.
 .IP CURLOPT_FTP_RESPONSE_TIMEOUT
 Pass a long.  Causes curl to set a timeout period (in seconds) on the amount
 of time that the server is allowed to take in order to generate a response