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Software components for data protection, secure storage and transfer

Why is the year reported incorrectly in directory listings?

FTPS protocol doesn't have a standard format for directory listings (see the exception below). Many modern FTP systems use so-called Unix listing format produced on Unix-based systems by "ls" tool. This listing specifies the year only when the file is X days or more away from current moment. If the file is closer to today than X days, then the time is listed instead and the year is omited.

And here comes the problem: the X is different on different systems. Some systems have X set to +/-183 days (i.e. 6 months in the past and 6 months in future) while others have X set to -365 days. There is no way to know how this X is set on the remote system.
SecureBlackbox use Linux approach with +/-183 days. MacOS X uses -365 days and there can be other combinations as well.

Example: if today is the 1st of July, 2015 and the listing date is "19th of November" -- is it 19 Nov 2015 or 19 Nov 2014 (future dates are possible for files, yes)? The answer depends on the value of X. If X = +/-183 then it's November '2015, and if the value of X is -365 then it's November '2014.

In general, if you don't like how ParseFileListEntry procedure works in the component, you can implement your own, more precise, parsing - that's all we can offer.

To address the problem there was an MLST/MLSD extension introduced. It is supported by some but not all servers. The extension means that there are MLST and MLSD commands supported, and those commands produce results in a well-defined uniform format suitable for machine parsing.

If your server supports this extension, you can make use of MLSD method to get the corresponding listings.

Additionally there's a ListDirectory() method in the recent versions of SecureBlackbox, which automatically chooses what command to use for the listing, so if MLSD is supported, you'll get correct listings with it.

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As of July 15, 2016 EldoS Corporation will operate as a division of /n software inc. For more information, please read the announcement.

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