Re: LYNX-DEV recovery of disrupted downloading

[David Woolley]

> 
> Please help me continue downloading from where it was interupted, I hope I
> don't
> have to start downloading all over again.
> 

The best solution to this is to use downloading tools rather than browsers,
although for ftp sites, you should note that there is an increasing trend
towards using the Microsoft ftp servers, and the standard one allows you to
restart, but only at byte offset 0 :(.++

A real Unix ftp client will allow a restart with servers that allow restarts.

The most recent generation of http servers also allow partial transfers,
permitting a restart, although ftp is usually a better protocol for bulk
downloads if it weren't the market's desire to only use one protocol for
all purposes, well matched or not.  I'm not 100% certain of the existence
of restartable http clients.

However, the current assumption for questioners who fail to specify OS is 
Windows 95.  I think wget can restart ftp and possibly http.  It has been
ported to Win32.  You should note that the maturity of the Win32 Lynx is
below that of the Unix builds and for serious downloading, you might want
to run Linux.

Note, if you don't have http_proxy and ftp_proxy set find the appropriate
values from your ISP and set them. This will improve performance on popular
but slow sites, and will usually allow you to abort a transfer and retry
a few hours later, but get it quickly from the cache.

One other point.  TCP/IP is very tolerant of broken links, it is dynamic 
IP addresses that cause the real problem.

++The de facto protocol (it's a standards violation) for restarted ftps is:

PORT n,n,n,n,n                    This is the IP address and port number to use
REST byte-offset                  REST=Restart
RETR filename                     RETR=Retrieve

The NT ftp server recognizes REST, but complains if the byte offset is
non-zero.