Re: MVS FTP interface (Was: Re: LYNX-DEV Two bugs in Lynx)

[Paul Gilmartin]

In a recent note, Jim Spath said:

> Date: Fri, 21 Feb 1997 06:35:40 -0500 (EST)
> 
Read RFC 1738.  It's very cleverly conceived.

> Anyway, what I'm wondering is how this pre-knowledge would be encrusted
> into "valid" URLs.  To use the FQDN, would this be appropriate: 
> 
> ftp:/some.big.iron/%27public.useful.data%27
> 
This should generate (after the login protocol):

    RETR 'public.useful.data'

which should be OK.

> which could be equivalent to:
> 
> ftp:/some.big.iron/%27public/useful/data%27
> 
No.  By RFC 1738, this generates:

    CWD 'public
    CWD useful
    RETR data'

With a couple syntax errors on unpaired apostrophes.  You should say
  ftp://some.big.iron/%27public%27/useful/data to get:
 
    CWD 'public '
    CWD useful
    RETR data

which should also be OK.

> and thence, the PQDN:
> ftp:/some.big.iron/useful.data
> 
> Since "/" is an invalid character for dataset names, Lynx should strip it,
> and only use "." and "'" when communicating with MVS servers.  Perhaps
> turn "/" into "." where the meaning of a subdirectory is implied? 
> 
See RFC 1738.  Largely, your guess is correct, but "/" isn't turned into
".".  Rather each unencoded "/" causes a separate CWD to be issued.  To
get "/" issued to the host, it must be encoded as "%2F".  Lynx doesn't
generally obey RFC 1738 on this point, mostly for historic reasons.

> It would also be useful to have Lynx do non-anonymous FTP to such systems,
> but I can't see how the prefix would be stored or used. 
> 
Remember that Web clients follow a connectionless paradigm.  Each
request starts with a new connection.  This mostly eliminates any
concern with remembering a prefix.

> BTW, Netscape fails on ftp://epaibm.rtpnc.epa.gov/ :-)
> 
Netscape, also, predictably, doesn't respect RFC 1738.

-- gil
;
; To UNSUBSCRIBE:  Send a mail message to address@hidden
;                  with "unsubscribe lynx-dev" (without the
;                  quotation marks) on a line by itself.
;