FTP commands are protocol elements, and are always expressed in
ASCII. FTP responses are composed of the numeric code, which is a
protocol element, and a message, which is often expected to convey
information to the user. It is not expected that users normally
interact directly with the protocol elements, rather the user-FTP
process constructs the commands, and interprets the results, in the
manner best suited for the particular user. Explanatory text in
responses generally has no particular meaning to the protocol. The
numeric codes provide all necessary information. Server-PIs are free
to provide the text in any language that can be adequately
represented in ASCII, or where an alternative language and
representation has been negotiated (see [7]) in that language and
representation.
Pathnames are expected to be encoded in UTF-8 allowing essentially
any character to be represented in a pathname. Meaningful pathnames
are defined by the server NVFS.
No restrictions at all are placed upon the contents of files
transferred using the FTP protocols. Unless the "media-type" fact is
provided in a MLSx response nor is any advice given here that would
allow determining the content type. That information is assumed to
be obtained via other means.
