- Ingmar Runge enhanced libcurl's FTP engine to support the PRET command. This

command is a special "hack" used by the drftpd server, but even though it is
  a custom extension I've deemed it fine to add to libcurl since this server
  seems to survive and people keep using it and want libcurl to support
  it. The new libcurl option is named CURLOPT_FTP_USE_PRET, and it is also
  usable from the curl tool with --ftp-pret. Using this option on a server
  that doesn't support this command will make libcurl fail.

include/curl/curl.h

@@ -413,6 +413,7 @@ typedef enum {
                                     wrong format (Added in 7.19.0) */
   CURLE_SSL_ISSUER_ERROR,        /* 83 - Issuer check failed.  (Added in
                                     7.19.0) */
+  CURLE_FTP_PRET_FAILED,         /* 84 - a PRET command failed */
   CURL_LAST /* never use! */
 } CURLcode;
 
@@ -1291,6 +1292,9 @@ typedef enum {
   /* set the SMTP mail receiver(s) */
   CINIT(MAIL_RCPT, OBJECTPOINT, 187),
 
+  /* FTP: send PRET before PASV */
+  CINIT(FTP_USE_PRET, LONG, 188),
+
   CURLOPT_LASTENTRY /* the last unused */
 } CURLoption;