CURLOPT_FAILONERROR with FTP to detect if a file exists or not, but it is
not working: http://curl.haxx.se/mail/lib-2008-07/0295.html
changelog of the current development status, as one or more of these problems
may have been fixed since this was written!
+58. It seems sensible to be able to use CURLOPT_NOBODY and
+ CURLOPT_FAILONERROR with FTP to detect if a file exists or not, but it is
+ not working: http://curl.haxx.se/mail/lib-2008-07/0295.html
+
57. On VMS-Alpha: When using an http-file-upload the file is not sent to the
Server with the correct content-length. Sending a file with 511 or less
bytes, content-length 512 is used. Sending a file with 513 - 1023 bytes,